Microplastics in Marine Food Webs

Full text

Microplasticsinmarinefoodwebs
OuSetälä
1
,MaijuLehniemi
1
,RachelCoppock
2,3
,MahewCole
2,3

1
MarineResearchCentre,FinnishEnvironmentInstute,P.O.Box140,00251Helsinki,Finland
2
MarineEcologyandBiodiversityGroup,PlymouthMarineLaboratory,PlymouthPL13DH,UnitedKingdom
3
CollegeofLifeandEnvironmentalScience:Biosciences,UniversityofExeter,ExeterEX44QP,UnitedKingdom

Microplastic debris is a globally‐pervasive contaminant, which presents a substantial risk to marine            
biota, food webs and ecosystems. Microplastics are heterogeneously distributed, with highest          
concentrations associated with the oligotrophic subtropical gyres, and relatively        
biologically‐productive semi‐enclosed seas and coastal waters. Encounter rates between biota and          
microplastics are driven by their geographical overlap and relative concentrations, as well as the             
characteristics of the plastic, and the motility, detection capabilities and feeding strategy of the             
organism. We identify four main routes via which microplastics can infiltrate marine food webs:             
ingestion, inhalation, entanglement and trophic transfer. Drawing upon established research and          
more recent exposure studies using microplastics, we highlight how plastics can be detected,            
ingested, processed and rejected by filter feeders. Finally, we consider how marine organisms can             
affect microplastics, by incorporating the plastic into biological matrices, through to the movement,            
redistributionandburialofplastic.

Introduction
A multude of food webs exist in the world's oceans, made up of a wide variety of organisms                 
that occupy disnct niches and possess different behavioral and feeding strategies. So far, only a              
small fracon of these taxa have been included in studies concerning microplasc debris in marine              
ecosystems. Microplascs (microscopic plasc debris, 100 nm ‐ 5 mm diameter) are now widely             
recognised as a pollutant of internaonal concern (Galgani et al., 2013; GESAMP 2016).            
Understanding the potenal impacts this prolific contaminant can have on marine life and food webs              
has become of intense interest, with an exponenal increase in research being conducted in recent              
years. In this chapter we explore how microplascs enter marine food webs, and consider the              
complex, iterave relaonship between microplascs, biota and biologically‐mediated ecological        
processes. Microplasc ingeson has been documented in animals throughout the marine food web,            
including zooplankton (Desforges et al., 2014), fish (Bellas et al., 2016; Lusher et al., 2013), marine               
mammals (Lusher et al., 2015; Bravo‐Rebolledo et al., 2013), turtles (Nelms et al., 2015) and seabirds               
(Tourinho et al., 2010). We explore the factors affecng microplasc consumpon and infiltraon            
into marine food webs, with consideraon given to spaal overlap, predator‐plasc raos, the            
properes of microplasc debris, and the life‐history and feeding‐strategies of biota demonstrated to            

consume plasc. At the individual level, microplascs pose a risk to the health of the organism;               
indeed, a growing number of experimental studies have demonstrated that at crical concentraons,            
microplascs can adversely affect feeding, energec reserves, reproducon, growth and survival in           
invertebrate and vertebrate species, including calanoid copepods (Cole et al., 2015; Lee et al., 2013),              
polychaete worms (Wright et al., 2013; Green et al., 2016), fish (Rochman et al., 2015) and oysters                
(Sussarellu et al., 2016). The latest evidence suggests that microplascs could also affect higher levels              
of biological organisaon, with populaon shis and altered behaviour impacng upon the ecological            
funcon of keystone species (Galloway et al., 2017). While the risks microplascs pose to individual              
biota are explored in greater detail in other chapters of this book, here we focus on how plascs have                  
the potenal to affect food webs and marine ecosystems as a whole. Furthermore, we consider how               
trophicinteraconsandecologicalprocessescanchangethemicroplascsthemselves.


INFOBOX1:Methodologicalapproach
Although microplascs are a relavely new topic in the environmental sciences, researchers           
have been able to learn from the experimental approaches and understanding gleaned from the             
fields of ecotoxicology, marine biology, and aquac chemistry. Basic mechanisms of feeding and            
energy transfer in marine food webs are well understood, and this knowledge has been useful in               
understanding observed interacons between microplascs and biota. Lessons learnt from         
nanoparcle research have been of parcular relevance to microplascs exposure studies,          
parcularly in respect to uptake mechanisms and mechanisms underpinning observed health effects,           
as well as developing sound ecological risk assessment (Syberg et al., 2015; Hüffer et al., 2017). In                
contrast, collecng field data on the distribuon and quanty of microplascs in different ecological             
compartments (water surface, water column, seafloor habitats, strandline) has turned out to be a             
significant challenge, requiring novel approaches, method development and opmisaon        
(Hidalgo‐Ruz et al., 2012; Lusher et al., 2017). An ongoing issue facing microplascs researchers is the               
absence of harmonised sampling or sample analyses protocols, and a forward challenge for the field              
istoworktowardsmethodologicalstandardisaon.


Theoverlapbetweenplasticsandbiota
Perhaps the most important variable affecng the flux of microplasc parcles into marine food             
websistheirabundanceanddistribuonintheenvironment,andphysicaloverlapwithbiota.

Geographicaloverlap

In recent years, there has been a concerted effort to idenfy the different habitats polluted              
with plasc debris, and ascertain the concentraons of microplascs across a wide range of aquac              
ecosystems. Microplascs are ubiquitous in the world´s oceans, and their presence in remote            
locaons, including the Arcc (Lusher et al., 2015), Antarcc (Waller et al., 2017), mid‐oceanic atolls              
(Do Sul et al., 2014) and the oceanic depths (Woodall et al., 2014), have highlighted their widespread                
distribuon. However, accurately determining the concentraons and type of microplascs present          
in seawater and sediments has proven a challenge. Adaptaons to tradional sampling techniques            
(e.g. trawls, sediment grabs; see review by Hidalgo‐Ruz et al., 2012) have proven invaluable for              
collecng samples, however isolang and idenfying microplascs has required a more novel           
approach (see INFOBOX 1). In recent years, a wide range of methodologies have been suggested for               
extracng and analysing plascs (see reviews by Lusher et al., 2017 and Miller et al., 2017), however                
the variety of methods employed can oen result in incomparable datasets. Analysing such data is              
further confounded by the heterogenous distribuon and temporal variability in microplasc          
concentraons.

Global sampling efforts have helped to idenfy ‘hotspots’ of plasc (Eriksen et al., 2014, Cozar              
et al., 2015, van Sebille et al., 2015). For example, the North Pacific, South Pacific and North Atlanc                 
subtropical oceanic gyres, which amass flotsam from throughout the oceanic basins, have all been             
highlighted as accumulaon zones for microplasc debris (Moore et al., 2001; Law et al., 2010;              
Eriksen et al., 2013). Oceanic gyres are largely oligotrophic and therefore relavely devoid of marine              
life, however for biota that can survive in the gyres, interacons with microplasc will be              
commonplace. For example, in the North Pacific gyre, Moore et al., (2001) observed a 6:1 plasc to                
plankton rao, and Goldstein & Goodwin (2013) idenfied 33% of gooseneck barnacles (Lepas spp.)             
had consumed between 1 and 30 items of microplasc. However, our understanding of the numbers              
and distribuon paerns of microplascs in marine environments is far from complete. This was             
pointed out already in the study dataset of >330 µm parcles from surface water tows, which               
showed smallest parcles to be most prevalent, but only down to a certain size group (1 mm) aer                 
which the concentraons decreased (Cozar et al., 2014). This absence of smaller plasc may result              
from difficules in idenfying very small parcles, or might be explained by bioc or abioc              
degradaonormovementoftheseplascs.

Enclosed and semi‐enclosed seas like the Mediterranean Sea and the Balc Sea have also been              
noted for their high microplasc concentraons (Collignon et al., 2914, Setälä et al., 2016b and              
Gewert et al., 2017) and thus have been proposed to accumulate plasc debris in greater amounts               
than open oceans (Fossi et al., 2016). As increasing concentraons inevitably increase the exposure             

of organisms at the base of the food webs, this may be the case also at higher trophic levels. In the                    
Mediterranean Sea, stomach analyses from large pelagic predators (swordfish and tuna) revealed           
that 18.5% of the fish examined contained microplascs. The reported concentraons of           
microplascs from the surface waters of another highly polluted semi‐enclosed sea basin, the Balc             
Sea, show how the microplasc concentraons in surface waters may significantly differ spaally            
(Setälä et al., 2016b, Gewert et al., 2017), and may reach high concentraons (up to 4.7 x 105 km
‐2
)                  
close to highly populated urban areas with low water exchange, or as was found by Gorokhova               
(2015), in deep water layers separated by a halocline. In the Balc Sea the field observaons of                
microplascs in the food web have mainly related to fish, herring being the most studied fish species.                
Bråte et al., (2017) analyzed the data from various studies on microplascs in fish from these Nordic                
waters; in the analyzed dataset consisng of 1425 individuals of Atlanc and Balc herring,             
microplasc ingeson varied between 0 and 30%. Ogonowski et al., (2017) reported that            
approximately 50% of herring individuals had ingested plascs along the Swedish coast in the Balc              
Sea, although the numbers of microplascs on individual fish were low (0‐1/fish), reflecng great             
variability between samples. In comparison, very low numbers of parculate microplascs (fibres           
were excluded) were also found in a recent study containing over 500 herring individuals from the               
open sea areas of the northern Balc Sea (Budimir et al., in press). The reported share of herring                 
with ingested microplasc parcles varies greatly between these studies, and may at least partly be              
explained by spaal differences in the overlap of microplascs and herring. Differences in methods             
used for extracng microplascs from fish ssue makes comparisons between studies difficult and            
conclusionsvague.

A recent study predicts the greatest overlap between microplascs and marine life will occur             
in coastal regions (Clark et al., 2016). Coastal waters and estuaries have relavely high biological              
producvity owing to their shallow, protected waters and fresh nutrional inputs from rivers, which             
are valued by aquaculture and fisheries, and encompass important nursery grounds for           
commercially‐exploited marine taxa. It is postulated that their proximity to sources of anthropogenic            
polluon (e.g. marime industry, urban areas, riverine inputs), puts them at high risk of microplasc              
polluon. Microplasc sampling in coastal regions is problemac owing to the density of organic             
material in these waters (Cole et al., 2014), nevertheless recent studies have highlighted the overlap              
between plascs and biota in coastal waters. In the English Channel, a 36.5% incidence of              
microplasc ingeson in demersal and pelagic fish species has been observed (Lusher et al., 2013),              
while 70% of brown shrimp (Crangon crangon) sampled from the coastlines of European countries            
along the English Channel have been shown to consume microplasc (Devriese et al., 2015). More              

recently, Steer et al., (2017) idenfied the rao of microplascs to fish larvae ranged from 1:27               
nearestPlymouth(UnitedKingdom),to1:135kmfromtheshoreline.

Habitats
Microplascs consist of a wide range of polymers which have their own special characteriscs             
that affect their distribuon in the water, and thereby which organisms and habitats are prone to               
plasc exposure. Local wind condions, water currents as well as geomorphology all affect the             
distribuon of microplascs in water and their spaal accumulaon (Barnes et al., 2009). The vast              
amounts of anthropogenic debris washing up on beaches across the globe (Browne et al., 2011)              
provides visual evidence of the efficiency with which floang plasc debris can be transported on the               
sea surface. Approximately half of marine plasc debris is inially buoyant (e.g. polystyrene,            
polyethylene, polypropylene), while denser plasc (e.g. polyvinylchloride, nylon) readily sinks in          
seawater. As observed from numerous sampling campaigns, microplascs can permeate throughout          
the water column, with plasc and microplasc debris, including low‐density polymer plasc, widely            
evidentinbenthicecosystems(Milleretal.,inpress).

Laboratory exposures have been used to demonstrate that bioc interacons including          
biofouling (Fazey and Ryan, 2016; Kaiser et al., 2017), egeson (Cole et al., 2013; Cole et al., 2016)                 
and bioturbaon (Näkki et al., 2017), as well as physical processes such as fragmentaon (Andrady,              
2017), can affect the properes and movement of plascs; it is hypothesised these processes could              
result in changes to the distribuon of microplascs within marine ecosystems where biota and             
plascs overlap (Figure 1; Clark et al., 2016). In these waters, we might expect a downwards flux of                 
plasc debris, resulng in an accumulaon of microplascs on the seafloor (Barnes et al., 2009,              
Woodall et al., 2014). However, it is important to recognise that vercal flux should be considered a                
redistribuon of plascs, and not a ‘removal’ mechanism. Benthic ecosystems can be highly            
biologically‐producve habitats, supporng a diverse array of life that play vital roles in the oceanic              
carbon pump (Turner, 2015), reef formaon (Beck et al., 2011) and bioturbaon (Cadee, 1976).             
Environmental sampling has idenfied plasc polluon in every benthic habitat invesgated,          
including highly remote areas such as both Arcc (Bergmann et al., 2017) and Antarcc (Munari et               
al., 2017) polar regions and the deep sea (Woodall et al., 2014, Bergmann et al., 2017). Plasc                
concentraons in sediments are highly variable, due in part to different sampling and extracon             
methodologies and also to the natural heterogeneity of sediments. Concentraons of up to 6,600             
microplascs kg
‐1 have been reported in Arcc sediments (Bergmann et al., 2017) and in a study of 42                 
sites around the Australian coastline (Ling et al., 2017), a regional average of 3,400 microplascs L
‐1
               
were reported, with the highest individual sample yielding 12,500 plascs L
‐1
. Laboratory exposures            

have shown that benthic invertebrates readily consume plasc, and this can have a detrimental             
impact on their health and funconality. A reducon in energy reserves (Wright et al., 2013b),              
reproducon (Sussarellu et al., 2016), metabolism and bioturbaon acvity (Green et al., 2016) have             
been reported in benthic organisms, with potenal impacts to ecosystem funconing (Volkenborn et            
al.,2007).


Figure 1. Potenal pathways for the transport of microplascs and its biological interacons (Source:            
Wrightetal.,2013).

Encounteringanddetectionofmicroplastics
Compared to the dynamic interacons between a predator/grazer and their natural prey, the            
relaonships between an animal and microplasc is somewhat simplified. The feeding mode and            
life‐history of an organism will affect both its encounter and ingeson rate of microplasc. Organisms              
may acvely select microplascs from the environment in search of prey or they may ingest them               
accidentallywhilefeedingonfoodparclesoranimalswhichcontainplasc.

Apassiveparticle
Microplascs are passive: freely floang on the water surface; suspended or slowly sinking in             
the water column; or, deposited on or within the seabed. Encounter rate (i.e. the commonality with               
which a predator comes into contact with it’s prey) is a crucial factor affecng the ingeson rate of                 

that prey (e.g. Evans, 1989). Primarily, encounter rate is influenced by the relave abundance of              
predator/grazer and prey; for microplasc ingeson to occur, there would need to be a significant              
spaal overlap between biota and plasc, and a substanal amount of plasc present for a likely               
encountertooccur.

Classic work on feeding efficiencies have shown how changes in prey density affect the             
ingeson rates of predators. Ingeson increases with an increasing prey density up to a saturaon              
point, whereby the predator cannot process more prey even though the prey density sll increases,              
as described by Solomon (1949) and Holling (1959). This has also been shown in laboratory studies               
with virgin microplascs and various invertebrate taxa: the more parcles the organisms were            
offered, the more they were ingested, even when working with the relavely high concentraons             
used in laboratory sengs (e.g. Cole et al., 2013, Setälä et al., 2016a). Gelanous organisms (e.g.               
jellyfish and ctenophores) may feed without reaching a saturaon level. This means that even in very               
high concentraons of prey they connue capturing them but start to egest/vomit prey that they are               
unable to process. However, it has been observed that jellyfish ingested relavely low numbers of              
microplascs compared to other filter feeders (e.g. copepods) in the South China Sea (Sun et al.,               
2017). The classical Holling‐type ingeson paerns may also be affected by clogging of feeding             
appendages. In such cases, a high concentraon of microplascs (fibres) may decrease feeding            
acvity,resulnginloweringesonrates.



Figure 2. Number of ingested 10 µm spheres (mean±SD) in blue mussel (Mytilus trossulus) at three             
different bead concentraons (Low = 5, medium = 50 and high = 250 beads mL
‐1
). Source: Setälä et                 
al.,(2016a).

Acve, mole predators (e.g. cruising predators) will encounter prey, and we therefore assume            
plasc, more readily as they move through the water or sediment. Non‐mole animals will encounter              
microplascs the same way they come into contact with suspended or deposited prey (i.e. water              
currents bringing parcles close enough for capture, or generang localised currents to draw            
suspended parcles to the organism). Sessile organisms are also not able to avoid exposure to              
microplascs, and are subjected to all parcles present in the suspension they are feeding in.              
However, passively floang and sessile organisms, and ambush predators, can compensate for          
reducedencounterratesthroughhigh‐efficientfilteringacvity(Greenetal.,2003).

Detectingmicroplastics
Animals detect prey using visual or chemical cues, or hydromechanical signals when idenfying            
mole prey moving through the water. Organisms relying upon visual detecon may mistake            
microplascs as prey. For example, ocean‐foraging Fulmars travel vast distances across the North            
Atlanc, relying on visual cues to select prey floang near the ocean surface; dissecons of Fulmars               
beached along European coastlines have rounely idenfied the seabirds’ stomachs are full of plasc             

(van Franeker et al., 2011). Researchers oen note that microplasc debris comes in a wide range of                
shapes, size and colour, however it is currently unclear whether these aributes have any influence              
onitslikelihoodofbeingconsumedbyanimalsrelyingonvisualdetecon.

The swimming acvity and speed of mole prey affects their encounter rate, with numerous             
studies establishing that acvely moving prey are detected more frequently and encountered more            
oen (Gerritsen & Strickler, 1977, Gerritsen, 1984, Tiselius et al., 1993). As microplascs are passive              
parcles, they cannot be detected using hydromechanical signals, and we would therefore expect            
them to be encountered less frequently than mole prey at similar concentraons. For example, in              
pelagic communies the swimming acvity of the predator is affecng the encounter rate of             
microplasc parcles in addion to their density and overall distribuon. However, as plasc            
parcles are non‐mole, they make easy targets for predators and may therefore be ingested (if not               
acvely rejected) more readily than natural prey which can incite escape‐responses (e.g. Green,            
2003),andmayrequireanacvecapturingprocess.

Chemical cues play a significant, but variable role in the prey selecon of marine organisms              
from invertebrates to mammals. For example fish have diversely developed olfactory organs (Hara,            
1975) for detecng signals related to reproducon and feeding. Some marine species possess highly             
developed chemosensory organs (e.g. sharks) while in some others they may be poorly developed,             
(e.g. visual predators like pike (Hara, 1975). Crustaceans, such as copepods are generally considered             
to be selecve feeders that display flexibility in their feeding behavior (Koehl and Sckler, 1981);              
discriminaon between prey can be based on size (Frost 1972), molity (Atkinson 1995) or chemical              
signals (Cowles et al.,1988). Not all chemicals are sensed; what is important is that in order for an                 
organism to receive a chemical smuli, the chemical itself should be soluble in water. Chemical              
signals can assist in the selecon for high‐quality food, determined by protein content (Cowles et al.,               
1988), or be used to avoid unsuitable prey (e.g. harmful algae containing toxic compounds like              
saxitoxin). However, acve avoidance of unsuitable or toxic prey by copepods is most likely a result of                
acommonhistory,i.e.co‐evoluonofthepreyandpredator(Colin&Dam,2002).

Field‐collected data and exposure experiments show that plasc parcles floang in the           
water and embedded in the sediment are rapidly colonized by rich microbial communies comprising             
of procaryoc and eucaryoc organisms, like bacteria and algae (Oberbeckmann et al., 2014,            
Harrison et al., 2014). So far there is very lile informaon on how the formaon of biofilm actually                 
affects the ingeson of microplascs. Recent studies show, that the effects of biofouling are most              
likely taxon‐ or even species‐specific. Vroom et al., 2017 idenfied that biofouling of polystyrene             

beads promoted ingeson by planktonic crustaceans, although this was somewhat dependent on           
taxon, size and stage of the grazers. For two of the three copepod species studied (Acartia longiremis               
and Calanus finmarchicus, excluding the adult females of the laer) it was shown that in most cases               
the fouled microplascs were ingested by more individuals and at higher rates than the unfouled              
plascs. However one copepod species, Pseudocalanus spp., did not ingest any of the microplasc             
parcles offered. Contradictory results were reported by Allen et al., (2017) who studied the             
ingeson of weathered, fouled and unfouled pre‐producon pellets (PS, LDPE and HDPE), by a             
scleracnian coral species known to use chemosensory cues for feeding. Their results showed that             
the corals ingested different types of plascs, consuming significantly more unfouled than fouled            
microplascsweretakenup. 
INFOBOX2:Experimentalwork
Most of the informaon that has so far been produced on the parameters affecng microplasc              
ingeson by marine organisms come from simplified laboratory experiments. Results from          
experimental work should not be directly applied to natural condions where confounding factors            
exist. When conducng environmentally relevant experimental work on ingeson and effects of           
microplascs in food webs, the concentraon, size and type of the used parcles should be adjusted               
to correspond to natural condions. At the moment there is sll a mismatch between “reality” and               
laboratory experiments. So far most experiments are run with microplasc concentraons higher           
than those commonly found in the environment, and with virgin parcles of uniform size and shape               
that fail to accurately represent the condions in the field (Phuong et al., 2016). This inconsistency is                
likely to influence our understanding of the marine microplasc problem as Ogonowski et al., (2016)              
showed in laboratory experiments comparing the effects of primary and secondary microplascs.           
They showed that secondary microplascs have more negave effects on feeding in a cladoceran,             
Daphnia magna,compared to primary microplascs commonly used in previous studies. The reason            
why experimental laboratory studies have not used microplasc concentraons commonly observed          
in marine environment is their “low” concentraons but also the uncertainty in assessing their             
concentraons. Microplasc concentraons found in marine environments vary significantly        
between areas and habitats but seem to be low when compared to the numbers of the real prey,                 
which makes environmentally relevant exposure studies difficult. Long lasng exposure experiments          
in mesocosms mimicking natural condions would be needed to more accurately assess the            
relaonshipsbetweenmicroplascsandtheirpotenalpredators.


Intothefoodwebs

The ingeson, entanglement or inhalaon of microplasc by marine organisms can be viewed            
as an entry point into marine food webs. Owing to their small size, microplascs are bioavailable to a                 
wide range of marine organisms, and can be both selecvely and accidentally ingested (Schuyler et              
al., 2012). The ingeson of microplasc parcles is affected by their concentraon, size, shape,             
distribuon and chemical character (i.e. density, chemical signal), and the animal’s feeding habits. In             
animals with developed organs for prey detecon, plasc polymers may thus not be selected or they               
mayberejectediftheyarerecognizedasbeingunfavorable,orifamorepreferablepreyisavailable.

Filterfeeding
Filter feeding organisms are prevalent throughout marine food webs, from small planktonic           
invertebrates and benthic taxa, to megafauna, where they feed on suspended organic material, such             
as algae, zooplankton, fish larvae and detritus. The size range of parcles that can be ingested by a                 
grazer depends on the feeding mode (e.g. filter feeding or raptorial), gape size and specific feeding               
mechanisms of the grazer/predator. For filter feeders, the actual size limits for the ingested prey are               
set by the structure and funcon of the filtering apparatus used for trapping parcles from the               
suspension (Riisgård and Larsen, 2010). Filtering devices in suspension feeding organisms are not            
simple sieves that mechanically clean the water from suspended parcles. The structures of filtering             
apparatus found in unicellular, invertebrate or vertebrate organisms differ greatly, both between and            
among taxa, with varying levels of adaptability and sensory capability. Parcle capture depends on             
parcle type (e.g. shape, size, density), parcle concentraon, water viscosity, the quanty of water             
that is filtered and filtering efficiency. Besides direct contact, the capturing mechanisms may also             
involve other factors, such as chemo‐ and mechanorecepon (Riisgård and Larsen, 2010). Moreover,            
experimentally measured clearance rates of plankton have been found to vary also depending on             
temperature, salinity and the type of prey that has been offered (e.g. Kiorboe, 1982, Garrido et al.,                
2013). Daily clearance rates of marine invertebrates can vary from microlitres (unicellular organisms,            
like ciliates), to millilitres (copepods), litres (bivalves), hundreds of litres (gelanous zooplankton), or            
more(baleenwhales).

Two parameters are commonly used to esmate the efficiency and outcome of filter feeding:             
ingeson and clearance rate. The ingeson rate denotes the number of prey parcles ingested per              
predator in a me unit. Ingeson rate can be experimentally esmated directly, through observaons             
of ingested prey parcles inside the organism, or indirectly, as the disappearance of prey from the               
experimental media over me. In the past, inert plasc parcles (spheres) have been used as              
surrogates for natural prey to esmate feeding parameters in planktonic organisms (Huntley et al.,             
1983, Borsheim, 1984, Nygaard et al., 1988,). These historical studies with Calanus and related             

copepod genera have demonstrated a preference for algae over polystyrene beads, alongside size            
selecvity (Fernandez 1979, Donaghay and Small, 1979, Huntley et al., 1983). However, observaons            
for such preferences do not necessarily hold for all developmental stages, which further complicates             
things, i.e. when exposure studies are being conducted. Clearance rate is a derivave of ingeson              
rate and is calculated by dividing the laer by prey concentraon. The clearance rate thus measures               
the water volume that an individual organism can clear of food parcles in a me unit. To understand                 
the probability of any suspended parcle to be ingested by a filter feeding organism, both the               
clearancerateandtheconcentraonofsuitablepreyshouldbetakenintoaccount.

From the viewpoint of a small filter‐feeding organism under natural condions, microplasc           
concentraons may be too low for rounely encountering a plasc parcle. However, in waters             
containing high concentraons of microplascs the situaon is different even for a small organism             
with a relavely low clearance rate and efficiency, such as a copepod. As an example, the               
experimentally defined daily clearance rates of common copepods may vary between ca. 10 to <200              
mL (Frost, 1975, Engström et al., 2000, Setälä et al., 2009). In theory, a copepod feeding for example                 
with a high clearance rate of 144 mL / day (Frost, 1975), at a concentraon of 9200 plascs m
‐3 as has                    
been observed from the Pacific Ocean (Deforges et al., 2014), a single microplasc would be ingested               
by every 0.7 copepods, assuming all parcles are edible and the animals are solely undertaking              
passive ingeson without rejecon of plasc. Assessments based on animals collected from the field,             
have also confirmed the role of zooplankton as entry points for microplascs to food webs. In the                
study of Desforges et al., (2015) which was based on analysis of the number of ingested microplascs                
from subsurface collected zooplankton and the overall distribuon of these species from the            
Northeast Pacific Ocean idenfied encounter of microplascs by zooplankton as 1 parcle per every             
34 copepods and 1 parcle per every 17 euphausiid. The authors further esmated that both the               
juvenile salmon as well as adult returning fish would be affected daily with ingested microplascs              
throughtheirzooplanktonprey.

Invertebrates with capacity for filtering larger quanes of water, and with a longer lifespan             
(e.g. bivalves), or large filter feeders (such as whales) may encounter microplascs far more             
frequently than zooplankton. Bivalves are one of the key organisms when entry points of             
microplascs to marine food webs are assessed. They are efficient suspension feeding animals that             
form links between the pelagic and benthic ecosystems and are a key source of prey for many marine                 
fish, birds and mammals. In the Balc Sea it has been assessed that within one year the blue mussel                  
beds would, in theory, filter a water volume equivalent to the whole sea basin (Kautsky and Kautsky,                
2000). The numbers of microplascs found in bivalves vary significantly ranging from less than 0.5              

parcles (Eastern Atlanc and Balc Sea) to over 100 parcles (Western Atlanc) per animal             
(Mathalon and Hill, 2014, Vandermeersch et al., 2015, Railo, 2017). Exposure of large filter feeders to               
microplascs has been shown by Fossi et al., (2014) aer examining concentraons of phthalates and              
organochlorine compounds of a basking shark and a baleen whale. The authors concluded that             
micro‐lier is ingested by these large filter feeders together with their neustonic prey. A comparave              
study carried out in two semi‐enclosed basins; the Mediterranean Sea and the Sea of Cortez in the                
Gulf of California (Fossi et al., 2016) gives supporng informaon indicang that fin whales in highly               
polluted areas are exposed to major health hazards due to microplascs and their co‐contaminants.             
Considering the vast amounts of water these animals filter (5,893 m
3
/day; Fossi et al., 2014), this               
conclusionismorethanrelevant.

INFOBOX3:Microplastics,anissueofsize
‘Microplasc’ is typically used to describe plasc parcles smaller than 5 mm in diameter, with              
a lower size limit of 100 nm; plascs larger than 5 mm are considered ‘macroplascs’, while plascs                
smaller than 100 nm in size are termed ‘nanoplasc’ (Cole et al., 2011). Using these size               
classificaons, the largest microplasc parcles (5000 µm) have a diameter 50,000 mes larger than             
the smallest microplasc (0.1 µm). Moreover, when we consider volume and surface area, these             
differences become even more apparent. Imagine a spherical shaped microplasc parcle, like the            
ones used in experimental studies, or the plasc microbeads commonly used in exfoliang personal             
care products: a 5 mm diameter bead is 1.25 x 10
14 
mes greater in volume and 2.50 x 10
9larger by                   
area than a 100 nm diameter bead. Of course most of the weathered microplasc parcles that are                
found in the marine environment are not uniform in shape, with fibrous, planar and irregularly              
shaped plasc being most prevalent. Nevertheless, differences in a parcle’s dimensions will have a             
significant impact on the risk they pose to marine life. For example, microplascs of different sizes               
may differ in their behaviour under marine condions (i.e. buoyancy), biological availability, and            
capacity to incite biological effects. Furthermore, the larger surface area to volume raos associated             
with smaller parcles greatly increases the plasc’s capacity for adsorbing (and potenally           
desorbing) water borne pollutants (e.g. persistent organic pollutants, hydrophobic organic         
contaminants) (Koelmans et al., 2016), up to one million mes greater than that found in the               
surroundingseawater(Matoetal.,2001)


Respiratoryintake

Venlaon has also been idenfied in exposure experiments as a means by which microplascs             
can be concentrated from the surrounding water. Was et al., (2014) idenfied that the shore crab               
(Carcinus maenas) was able to respire polystyrene microbeads, which accumulated on the surface of            
their gills. Blue mussels (Mytilus trossulus) and Balc clams (Macoma balthica) have also been shown            
to accumulate microplasc parcles to their gills aer 24 h incubaons; however, the bead             
concentraonsweremuchhigherinthedigesvetractsofthesameanimals(Setäläetal.,2016a).

Entanglement
Numerous organisms have been shown to entangle with fibers or larger plascs (e.g. Laist,             
1997, Cole et al., 2013, NOAA 2014, Taylor et al., 2016). They may be found in the swimming or                  
feeding appendages of invertebrates, in the valve gapes of bivalves or entangled around larger             
animals. Entanglement with fibers in field collected animals has been observed even in remote areas              
such as the deep seas, where fibers were found on sea pens and hermit crabs (Taylor et al., 2016).                  
When these organisms are eaten by higher trophic level predators the plascs adhered to external              
surfacesoftheorganismswillbeeatenaswell.

Trophictransfer
Once ingested, microplascs will either be egested or retained by the organism. If a predator              
consumes an organism that has retained microplasc, the predator will be indirectly consuming this             
plasc as part of its diet, in a process referred to as ‘trophic transfer’. The trophic transfer of plasc                  
has been documented in predatory Norway lobsters (Nephrops norvegicus) that consumed         
polypropylene rope fibres embedded in fish (Murray and Cowie, 2011); shores crabs (Carcinus            
maenas) that indirectly ingested fluorescent polystyrene 0.5 µm and 10 µm microspheres present in             
common mussels (Mytilus edulis) (Farrell and Nelson, 2013; Was et al., 2014); mysid shrimps            
(Neomysis integer) that consumed fluorescent polystyrene 10 µm spheres previously taken up by           
mesozooplankton (Setälä et al., 2014); and, fish (Gasterosteus aculeatus) that consumed an insect           
larvae containing microbeads in a mesocosm experiment (Lehniemi and Setälä, unpublished). The           
trophic transfer of microplascs and associated POPs from Artemia nauplii to zebrafish (Danio rerio)           
was also verified in a laboratory experiment (Batel et al., 2016) and microplasc debris found in               
faecal pellets of predatory seabirds (great skuas, Stercorarius skua) was greatest when correlated           
withremainsofsurfacefeedingNorthernfulmars(Fulmarusglacialis)(Hammeretal.,2016).

For trophic transfer to occur, microplasc must be consumed alongside the prey. This includes             
plasc adhered to algae (Bhaacharya et al., 2010, Gutow et al., 2015), or the external surfaces of an                 
animal (e.g. entrapped in the setae of a copepods’ appendages; Cole et al., 2013), or retained               

indefinitely within the organism itself. Plascs are commonly observed in the intesnal tract of             
marine animals, including seabirds (van Franeker & Law, 2015), fish (Lusher et al., 2013),             
invertebrates (Murray and Cowie, 2011) and turtles (Nelms, 2016); this occurs where larger plascs             
or coalesced polymeric fibres cause a gut blockage, prevenng the plasc from being shied via              
peristalc acon. In the common shore crab (Carcinus maenas), polystyrene microspheres have been           
observed to lodge between the microvillae which line the stomach, resulng in prolonged gut             
retenon mes. In copepods, starvaon has been observed to increase gut retenon mes, with 10              
µm polystyrene microspheres remaining in the intesnal tracts of Calanus helgolandicus for up to 7             
days, far exceeding the typical gut passage mes of just 2 hours (Cole et al., 2013). In the common                  
mussel (Mytilus edulis), 3.0‐9.6 µm polystyrene microspheres have been demonstrated to translocate          
into the circulatory fluid (haemolymph), where they can remain for in excess of 48 days (Browne et                
al., 2008; von Moos et al., 2012). Owing to their small size, nanoplascs (<100 nm diameter) have the                 
capacity to cross epithelia, and therefore have the capacity to enter ssues and circulatory fluids, for               
example in dendric cells that transport small parcles (eg. bacteria) across gut epithelial cell walls              
(Rescignoetal.,2001).

In numerous aquac ecosystems, persistent chemical pollutants (i.e. PCBs, PAHs and methyl           
mercury) have been shown to biomagnify as they pass up the food chain (reviewed by Blais et al.,                 
2007). The increasing body burdens of such pollutants in higher trophic organisms arises from the              
hydrophobicity of these chemicals, resulng in their accumulaon within fay ssues of prey            
species. So far, there have been no quantave measures of microplascs passing up the food chain,               
and it therefore remains unclear whether plascs will biomagnify in marine food webs.            
Biomagnificaon will largely depend upon the transience of plascs in an organism, with            
biomagnificaon only occurring where plascs are readily ingested and retained. Retenon of           
plascs can be influenced by food availability (Cole et al., 2013; Was et al., 2014) and shape (Murray                 
and Cowie, 2001), but will be predominantly governed by the size of the plasc (Galloway, 2015). In                
Figure 3. we predict how the size of a plasc parcle is likely to relate to the probability of that                   
microplascbiomagnifyingupthefoodchain.



Figure 3. Considering how microplasc size might influence the probability of biomagnificaon of           
plascs occurring in a food chain. (1) Very small (i.e. nano) plascs are readily absorbed by the gut                 
and are retained within the circulatory fluid and/or ssues; (2) Moderately sized plascs are ingested,              
are present within the organism during gut transit, and then readily egested; (3) Larger and fibrous               
plascs are ingested but, owing to their size, remain in the intesnal tract; (4) The largest               
microplascsareinedibletoorganismsatthebaseofthefoodchain.


Alteration,repackagingandtransportofmicroplasticswithinmarinefoodwebs
In this secon, we consider how marine organisms, trophic dynamics and biologically‐mediated           
ecological processes can alter the fate of a microplasc, and highlight how microplascs might             
impingeonbiota,foodwebsandthemarineecosystems.

Biologicaltransportofmicroplastic
Microplascs consumed, respired or adhered by an organism will be subject to passive,            
biologically‐mediated transportaon, with both vercal and lateral movement to be expected across           
a variety of habitats (e.g. water column, sediments). The distances by which microplascs can be              
transported via a biological vector will largely depend on the movement, migratory routes and gut              
transitmesoftheindividualorganism.


Figure 4. How biota transport microplascs within marine ecosystems. Image by Mahew Cole           
(originalcontent).

Diel vercal migraons, a synchronous daily migraon of a wide range of taxa, have been              
highlighted as a potenal route by which microplascs could be transported from the sea surface to               
deeper waters (Cole et al., 2016b; Clark et al., 2016). Organisms may ingest plascs whilst feeding at                
the surface at night, which can then be egested hundreds of meters below the surface. For example,                
a large (2‐3 mm) copepod swimming at speeds of between 30–90 m h
‐1 (Enright, 1977), with a gut                 
evacuaon me of approximately 2 hours (Cole et al., 2013), could vercally transport microplasc to              
depths of 60‐180 m. Lusher et al., (2016) idenfied that 11% of mesopelagic fish caught in the                
Northeast Atlanc had microplascs in their digesve tracts, and although it was unknown at what              
depth these plascs were consumed, the majority of species idenfied undergo diel vercal            
migraon and follow their zooplankton prey to the surface to feed; it is therefore plausible to suggest                

that ingeson of the microplascs may have occurred at the surface whilst feeding, and egested at               
depth.

The geographical distribuon of marine plasc has largely been considered from a physical            
perspecve, with abioc processes (i.e. wind, rivers, oceanic currents) expected to be the dominant             
factors in distribung this pervasive pollutant (Sherman and van Sebille, 2016). We consider that             
migratory species could also facilitate the transport of plascs. Migratory species have been widely             
demonstrated to play a vital role in the long‐range transport of persistent pollutants (e.g. PCBs, DDT,               
methyl mercury; Blais et al., 2007). For example, migratory fish (e.g. trout, salmon) have been shown               
to accumulate persistent organochlorines in their ssues while feeding in marine habitats, which are             
released in their eggs during spawning at otherwise prisne, freshwaters sites (Krummel et al., 2003;              
Mu et al., 2004). Numerous migratory species, including turtles (Nelms et al., 2015), ocean‐foraging             
seabirds (van Franeker, 2015), and cetaceans (Lusher et al., 2015), are rounely sampled with plascs              
in their intesnal tracts. These animals undertake large scale, annual migraons; for example, the             
Gray whale (Eschrichtius robustus) travels 6000 km annually from the coast of Mexico to the Chukchi              
Sea, and the Arcc tern (Sterna paradiasaea) migrates 19,000 km from Greenland to the Antarcc             
each year (Alerstam et al., 2003). The egeson of plasc within faeces, scat or guano, the               
regurgitaon of plascs by seabirds when feeding their young (Sileo et al., 1990), or the death of the                 
animal, will all contribute to the deposion of plasc in terrestrial, freshwater or marine habitats far               
fromthewaterswheresuchplascwasingested.

Incorporationofmicroplasticsintobiologicalmatrices
Within the marine environment, microplascs are rapidly colonized by ‘biofilms’, made up of            
microorganisms, plants and epibionts that aach and grow on substrates. The characteriscs of the             
biofilm that forms on a plasc will be influenced by the polymer, and the biological or ecological                
matrix through which it has passed; as such, the microbial complex that forms on the surface of                
plascs may act as a tracer of the journey of a microplasc within marine compartments (Galloway               
et al., 2017). The development of a biofilm can change the characteriscs of the plasc polymer, for                
example by increasing their mass (Lobelle and Cunliffe, 2011; Zeler et al., 2013; Rummel et al.,               
2017), and altering their chemical signal (see Detecting microplastics). It has been postulated that            
biofilm formaon could be enough to cause otherwise buoyant plascs to sink or oscillate within the               
water column, depending on the size and density of the plasc (Ye & Andrady, 1991, Kooi et al.,                 
2017).


In bivalves, feeding or rejecon of parcles that are suspended in the water is the outcome of                
passive and acve selecon. The size of the parcles that may be ingested depends on the filtraon                
apparatus of the parcular species. In Pacific oyster (Crassostrea gigas) larvae, uptake of polystyrene            
microbeads was size dependent, with microplascs larger than the oral groove unable to be ingested,              
while smaller plascs were readily consumed (Cole & Galloway, 2015). If the size is right, and prey is                 
directed to the specialized feeding organs (ctenidium) it may sll be rejected as pseudofaeces if              
considered unpalatable. Studies made with blue mussels have shown that the idenficaon of            
unsuitable parcles and their sorng in suspension‐feeding bivalves takes place in the           
lecn‐containing mucus that covers feeding organs, where interacon with carbohydrates from          
suspension takes place (Espinosa et al., 2010). Mussels (Mytilus edulis) have been visualised rejecng            
nanopolystyrene (Ward & Koch, 2009), and microplasc polyvinylchloride in their pseudofaeces          
(personal observaons of authors). The fate of microplascs incorporated into pseudofaeces remains           
unclear.

Ingested microplascs will typically be passed along the intesnal tract through peristalc           
acon. Within the intesnal tract microplascs will either be adsorbed across the gut lining, become              
entrapped in the gut (i.e. intesnal blockage causing retenon of plasc), or become incorporated             
into the animal’s faeces and egested. Microplascs have been idenfied in the faecal pellets of              
copepods (Cole et al., 2013), and it is assumed most animals that consume plascs will then egest                
them. Microplascs have been observed in commercially caught fish (e.g. Lusher et al., 2013), and              
whilst there is currently no data to explain the fate of plasc post ingeson, it could be assumed that                  
the majority would pass through the gut and get packaged in faecal pellets. The repackaging of               
plasc into the faeces of an animal will alter the properes (i.e. relave buoyancy) of the plascs                
within the water column (Cole et al., 2015), and represent an alternate route by which plascs can be                 
transferredwithinmarineecosystems(Clarketal.,2016).

Sinking faeces and marine aggregates play a vital role in the biological pump, whereby carbon              
and nutrients in the euphoc zone are repackaged, and transported to the ocean depths (Turner,              
2014). Faeces from anchovies in the producve upwelling system off the coast of Peru were observed               
as a key contributor to downward flux in sediment traps, with faecal sinking rates averaging >1 km d
‐1
                 
(Staresinic et al., 1983). In this scenario, any microplascs contained within these pellets may reach              
benthic sediments within a very short space of me. However, experimental work has documented             
that the incorporaon of microplascs into faecal pellets (Cole et al., 2016) and marine aggregates              
(Long et al., 2015), will alter the buoyancy of the biological matrix. Many carbon flux studies have                
concluded that slowly sinking faeces are unlikely to reach the seabed, instead becoming repackaged             

through coprophagy (i.e. the consumpon of faecal maer) by larger zooplankton species (Turner,            
2002), or broken down through microbial acon. In faeces containing microplasc, coprophagy           
would therefore represent a route by which plascs can re‐enter the marine food web. This has been                
demonstrated with copepods, when polystyrene microplascs ingested by the small copepod,          
Centropages typicus, were egested in their faecal pellets and subsequently ingested by the larger            
copepod, Calanus helgolandicus (Cole et al., 2016). The study further highlighted that          
microplasc‐laden pellets were more prone to fragment, making them more bioavailable to           
detrivoresduringtheirdescentthroughthewatercolumn.

Thefateofmicroplasticsinbenthicecosystems
Benthic sediments have been idenfied as an important sink for microplascs, including high‐density            
plascs which readily sele out of the water column, and lower‐density plascs whose movement to              
the benthos is facilitated by biological matrices. Highly polluted coastal sediments may comprise 3%             
microplascs (Carson et al., 2011), whilst esmates of 4 billion bioplasc and polymer fibres per km
2
               
are reported in Indian seamount sediments (Woodall et al., 2014). Within sediments, microplascs            
become bioavailable to benthic dwelling fauna, including important commercial species such as           
Norwegian lobster, Nephrops norvegicus (Murray & Cowie, 2011) and shellfish (Rochman et al.,           
2015). A number of papers having highlighted the capacity for benthic organisms, including bivalves             
(Sussarellu et al., 2016), echinoderms (Graham & Thompson, 2009) and polychaetes (Wright et al.,             
2013, Besseling et al, Green et al., 2016) to ingest microplascs, with the potenal to incite negave                
health effects with repercussions for their funconality (i.e. reduced bioturbaon acvity, reduced           
energec reserves). As with pelagic organisms, it is hypothesised that benthic taxa can alter the              
properes of microplascs, and through bioturbaon move plascs from the sediment‐water          
interface deeper into sediments. This has been evidenced in polychaetes and clams that transported             
microplasc fibres (polyethylene fishing line <1 mm) to depths of 1.7‐5.1 cm during a three week               
mesocosm experiment (Näkki et al., 2017). However, determining the capacity for sediment‐dwelling           
biota to redistribute plasc under natural condions remains unknown, and it is unclear whether             
bioturbaoncanresultinthepermanentburialofthisplasc.

Conclusions
Microplascs are under extensive research, and their complex interacons with marine food webs            
are becoming increasingly evident. Microplascs are pervasive, environmentally‐persistent parcles,        
which have the potenal to flux between the water column, seabed and biota. Nano‐ and              
microplascs can enter marine food webs via a number of entry‐points, and can subsequently be              
cycled through different bioc compartments; these bioc processes can result in changes to the             

properes and movement of the microplasc. Parameters governing the entrance of microplascs           
into food webs include the spaal overlap of microplascs and biota, the feeding strategy and              
molity of the organism, and the characteriscs of the plasc. From the studies carried out so far, we                 
have learned that different taxa, species, and developmental stage of a species, will each process,              
handle and react to microplascs in a myriad of ways. Some organisms have mechanisms that              
protect them from consuming anthropogenic contaminants, while others readily ingest large          
numbers of microplasc parcles together with their natural prey. With microplasc polluon in the             
marine environment becoming a growing threat, the numbers of both primary‐ and secondary            
microplascs is increasing. There may therefore come a me, when the exposure experiments which             
are carried out today, and which have been cricized because of their high microplasc             
concentraons, will be considered as “historic” research with environmentally relevant         
concentraons.

Funding
OS and ML acknowledge Ministry of Environment and Academy of Finland (MIF 296169) for funding.              
RLC is funded through a Natural Environment Research Council GW4+ PhD studentship           
(NE/L002434/1). MC acknowledges funding from the Natural Environment Research Council         
discoverygrant(NE/L007010).

References
Allen, A.S., Seymour, A.C. & Rischof, D. (2017). Chemorecepon drives plasc consumpon in a             
hardcoral.MarinePollutionBulletin.124(1),198‐205.
Alerstam, T. Hedenström, A., & Åkesson, S. (2003). Long‐distance migraon: evoluon and           
determinants.Oikos.103(2),247‐260.
Andrady, A.L. (2017). The plasc in microplascs: A review. Marine Pollution Bulletin. 119(1),            
12–22.
Atkinson, A. (1995). Omnivory and feeding selecvity in five copepod species during spring in the              
BellingshausenSea,Antarcca.ICESJournalofmarineScience.52(3‐4),385‐396.
Barnes, D.K., Galgani, F., Thompson, R.C., & Barlaz, M. (2009). Accumulaon and fragmentaon of             
plasc debris in global environments. Philosophical Transactions of the Royal Society of           
London.SeriesB,BiologicalSciences.364(1526),1985–1998.
Batel, A., Lin, F., Scherer, M., Erdinger, L., & Braunbeck, T. (2016). The transfer of benzo [a] pyrene                 
from microplascs to Artemia nauplii and further to zebrafish via a trophic food web             
experiment–CYP1A inducon and visual tracking of persistent organic pollutants.        
EnvironmentalToxicologyandChemistry.35(7),1656–1666.
Beck, M.W., Brumbaugh, R.D., Airoldi, L., Carranza, A., Coen, L.D., Crawford, C., Defeo, O., Edgar,              
G.J., Hancock, B., Kay, M.C. & Lenihan, H.S. (2011). Oyster reefs at risk and recommendaons              
forconservaon,restoraon,andmanagement.Bioscience.61(2),107‐116.

Bellas, J., Marnez‐Armental, J., Marnez‐Camara, A., Besada, V. & Marnez‐Gomez, C. (2016).           
Ingeson of microplascs by demersal fish from the Spanish Atlanc and Mediterranean           
coasts.MarinePollutionBulletin.109(1),55‐60.
Bergmann, M., Wirzberger, V., Krumpen, T., Lorenz, C., Primpke, S., Tekman, M.B. & Gerdts, G.              
(2017). High quanes of microplasc in Arcc deep‐sea sediments from the HAUSGARTEN           
observatory.EnvironmentalScience&Technology.51(19),11000‐11010.

Besseling, E., Wegner, A., Foekema, E.M., Van Den Heuvel‐Greve, M.J. & Koelmans, A.A. (2012).             
Effects of microplasc on fitness and PCB bioaccumulaon by the lugworm Arenicola marina            
(L.).EnvironmentalScience&Technology.47(1),593‐600.
Bhaacharya, P., Lin, S., Turner, J.P. & Ke, P.C. (2010). Physical adsorpon of charged plasc              
nanoparcles affects algal photosynthesis. The Journal of Physical Chemistry C: Nanomaterials          
andInterfaces.114(39),16556.
Blais, J.M., Macdonald, R.W., Mackay, D., Webster, E., Harvey, C. & Smol, J. P. (2007). Biologically               
mediated transport of contaminants to aquac systems. Environmental Science & Technology.          
41(4),1075‐1084.
Borsheim, K. Y. (1984). Clearance rates of bacteria sized parcles by freshwater ciliates measured             
withmonodispersefluorescentlatexbeads.Oecologia(Berlin).63,286−288.
Bravo Rebolledo, E.L., Van Franeker, J.A., Jansen, O.E. & Brasseur, S.M. (2013). Plasc ingeson by              
harbourseals(Phocavitulina)intheNetherlands.MarinePollutionBulletin.67,200–202.
Bråte, I.L.N., Huwer, B., Thomas, K.V., Eidsvoll, D.P., Halsband, C., Carney Almroth, B. & Lusher, A.               
(2017). Micro‐and macro‐plascs in marine species from Nordic waters. Nordic Council of           
Ministers.101p,48‐49.DOI:10.6027/TN2017‐549
Browne, M.A., Dissanayake, A., Galloway, T.S., Lowe, D.M. & Thompson, R.C. (2008). Ingested            
microscopic plasc translocates to the circulatory system of the mussel, Mylus edulis (L.).            
EnvironmentalScience&Technology.42(13),5026‐5031.
Browne, M.A., Crump, P., Niven, S.J., Teuten, E., Tonkin, A., Galloway, T.S. & Thompson, R.C.              
(2011). Accumulaon of microplasc on shorelines worldwide: sources and sinks.         
EnvironmentalScience&Technology.45(21),9175‐9179.
Budimir, S., Setälä, O. & Lehniemi, M. (in press). New praccal and affordable extracon method              
shows low numbers of microplascs in offshore plankvorous fish from the northern Balc            
Sea.MarinePollutionBulletin.
Cadée, G.C. (1976). Sediment reworking by Arenicola marina on dal flats in the Dutch Wadden             
Sea.NetherlandsJournalofSeaResearch.10(4),440‐460.
Carson, H.S., Colbert, S. L., Kaylor, M. J. & McDermid, K.J. (2011). Small plasc debris changes               
water movement and heat transfer through beach sediments. Marine Pollution Bulletin. 62,           
1708−1713.
Clark, J., Cole, M., Lindeque, P. K., Fileman, E., Blackford, J., Lewis, C., Lenton, T.M. & Galloway, T. S.                  
(2016). Marine microplasc debris: a targeted plan for understanding and quanfying          
interaconswithmarinelife.FrontiersinEcologyandtheEnvironment.14(6),317–324.

Cole, M., Lindeque, P., Halsband, C., & Galloway, T. S. (2011). Microplascs as contaminants in the               
marineenvironment:Areview.MarinePollutionBulletin.62(12),2588–2597.
Cole, M., Lindeque, P., Fileman, E., Halsband, C., Goodhead, R., Moger, J. & Galloway, T.S. (2013).               
Microplascingesonbyzooplankton.EnvironmentalScience&Technology.47,6646‐6655.
Cole, M. & Galloway, T.S. (2015). Ingeson of nanoplascs and microplascs by Pacific oyster             
larvae.EnvironmentalScience&Technology.49,14625–14632
Cole, M., Lindeque, P., Fileman, E., Halsband, C., Galloway, T.S. (2015). The impact of polystyrene              
microplascs on feeding, funcon and fecundity in the marine copepod Calanus helgolandicus.           
EnvironmentalScience&Technology.49(2),1130‐1137.
Cole, M., Lindeque, P. K., Fileman, E., Clark, J., Lewis, C., Halsband, C., & Galloway, T. S. (2016).                 
Microplascs Alter the Properes and Sinking Rates of Zooplankton Faecal Pellets.          
EnvironmentalScience&Technology.50(6),3239–3246.
Colin, S.P. & Dam, H.G. (2002). Effects of the toxic dinoflagellate Alexandrium fundyense on the             
copepod Acartia hudsonica: a test of the mechanisms that reduce ingeson rates. Marine          
EcologyProgressSeries.248,55‐65.
Collignon, A., Hecq, J. H., Galgani, F., Voisin, P., Collard, F., & Goffart, A. (2012). Neustonic               
microplasc and zooplankton in the North Western Mediterranean Sea. Marine Pollution          
Bulletin.64(4),861‐864.
Cowles T.J., Olson R.J. & Chisholm S.W. (1988). Food selecon by copepods: discriminaon on the              
basisoffoodquality.MarineBiology.100,41‐49.
Cózar, A., Sanz‐Marn, M., Mar, E., González‐Gordillo, J.I., Ubeda, B., Gálvez, J.Á., Irigoien, X. &              
Duarte, C.M. (2015). Plasc accumulaon in the Mediterranean Sea. PLoS One. 10(4)          
.e0121762.
Desforges, J.P.W., Galbraith, M., Dangerfield, N. & Ross, P.S. (2014). Widespread distribuon of            
microplascs in subsurface seawater in the NE Pacific Ocean. Marine Pollution Bulletin. 79,            
94e99.
Desforges, J.P.,W., Galbraith, M. & Ross, P.S. (2015). Ingeson of Microplascs by Zooplankton in             
the Northeast Pacific Ocean. Archives of Environmental Contamination and Toxicology. 69(3),          
320–330.
Donaghay, P.L. & Small, L.F. (1979). Food selecon capabilies of the estuarine copepod Acartia             
clausi.MarineBiology.52,137e146.
Do Sul, J.A.I., Costa, M.F. & Fillmann, G. (2014). Microplascs in the pelagic environment around              
oceanic islands of the Western Tropical Atlanc Ocean. Water, Air & Soil Pollution. 225(7) 2004.              
doi.org/10.1007/s11270‐014‐2004‐z
Devriese, L.I., van der Meulen, M.D., Maes, T., Bekaert, K., Paul‐Pont, I., Frère, L., Robbens, J. &                
Vethaak, A.D. (2015). Microplasc contaminaon in brown shrimp (Crangon crangon, Linnaeus         
1758) from coastal waters of the Southern North Sea and Channel area. Marine pollution             
Bulletin.98(1),179‐187.

Engström, J., Koski, M., Viitasalo, M., Reinikainen, M., Repka, S., & Sivonen, K. (2000). Feeding              
interacons of the copepods Eurytemora affinis and Acartia bifilosa with the cyanobacteria         
Nodulariasp.JournalofPlanktonResearch.22(7),1403‐1409.
Enright, J. T. (1977). Copepods in a hurry: Sustained high‐speed upward migraon. Limnology &             
Oceanography.22,118–125.
Eriksen, M., Maximenko, N., Thiel, M., Cummins, A., Lan, G., Wilson, S., Hafner, J., Zellers, A. &                
Rifman, S. (2013). Plasc polluon in the South Pacific subtropical gyre. Marine Pollution            
Bulletin.68(1),71‐76.
Eriksen, M., Lebreton, L.C.M., Carson, H.S., Thiel, M., Moore, C.J., Borerro, J.C., Galgani, F., Ryan,              
P.G. & Reisser, J. (2014). Plasc polluon in the world's oceans: 5 trillion plasc pieces weighing               
over250.000tonsafloatatsea.PLoSOne.9(12),1‐15.DOI:10.1371/journal.pone.0111913
Espinosa, E.P., Hassan, D., Ward, J.E., Shumway, S. & Allam, B. (2010). Role of Epicellular Molecules               
intheSeleconofParclesbytheBlueMussel,Mytilusedulis.BiologicalBulletin.219,50‐60.
Evans, G.T. (1989). The encounter speed of moving predator and prey. Journal of Plankton             
Research.11,415‐417.
Farrell P. & Nelson, K. (2013). Trophic level transfer of microplasc: Mytilus edulis (L.) to Carcinus               
maenas(L.).EnvironmentalPollution.177,1–3.
Fazey, F.M. & Ryan, P.G. (2016). Biofouling on buoyant marine plascs: An experimental study into              
theeffectofsizeonsurfacelongevity.EnvironmentalPollution.210,354‐360.
Fernandez, F. (1979). Parcle selecon in the nauplius of Calanus pacificus. Journal of Plankton           
Research.1(4),313‐328.
Fossi, M.C., Coppola, D., Baini, M., Gianne, M., Guerran, C. & Marsili, L. (2014). Large filter               
feeding marine organisms as indicators of microplasc in the pelagic environment: the case            
studies of the Mediterranean basking shark (Cetorhinus maximus) and fin whale (Balaenoptera          
physalus).MarineEnvironmentalResearch.100,17‐24.
Fossi, M.C., Marsili, L., Baini, M., Gianne, M., Coppola, D. & Guerran, C. (2016). Fin whales and                
microplascs: the Mediterranean Sea and the Sea of Cortez scenarios. Environmental Pollution.          
209,68–78.
Frost, B.W. (1972). Effects of size and concentraon of food parcles on the feeding behaviour of               
themarineplanktoniccopepodCalanuspacificus.Limnology&Oceanography.17,805‐815.
Galgani,F.,Hanke,G.,Werner,S.D.V.L.&DeVrees,L.(2013).MarinelierwithintheEuropean
marinestrategyframeworkdirecve.ICESJournalofMarineScience.70(6),1055‐1064.
Galloway,T.S.(2015).Micro‐andnano‐plascsandhumanhealth.InMarineanthropogeniclitter
(pp.343‐366).SpringerInternaonalPublishing.
Galloway,T.S.,Cole,M.&Lewis,C.(2017).Interaconsofmicroplascdebristhroughoutthe
marineecosystem.NatureEcology&Evolution.1,0116.
Garrido S., Cruz, J., Santo, M. & Saiz, E. (2013). Effects of temperature, food type and food                
concentraon on the grazing of the calanoid copepod Centropages chierchiae. Journal of           
PlanktonResearch.35(4),843–854.

Gerritsen, J. (1984). Size efficiency reconsidered: a general foraging model for free‐swimming           
aquacanimals.TheAmericanNaturalist.123,450‐467.
Gerritsen, J. & Strickler, J. R. (1977). Encounter probabilies and community structure in            
zooplankton: a mathemacal model. Journal of the Fisheries Research Board of Canada. 34,            
73‐82.
GESAMP‐JointGroupofExpertsontheScienficAspectsofMarineEnvironmentalProtecon
(2016).Sources,fateandeffectsofmicroplasticsinthemarineenvironment:Part2ofaglobal
assessment.ReportNo.93.Editors:P.J.Kershaw&C.M.Rochman.URL:www.gesamp.org.
Gewert,B.,Ogonowski,M.,Barth,A.&MacLeod,M.(2017).Abundanceandcomposionofnear
surfacemicroplascsandplascdebrisintheStockholmArchipelago,BalcSea.Marine
PollutionBulletin.120,1‐2.
Graham,E.R.&Thompson,J.T.(2009).Deposit‐andsuspension‐feedingseacucumbers
(Echinodermata)ingestplascfragments.JournalofExperimentalMarineBiologyandEcology.
368(1),22‐29.
Green, S., Visser, A.W., Titelman, J. & Kiørboe, T. (2003). Escape responses of copepod nauplii in               
theflowfieldofthebluemussel,Mytilusedulis.MarineBiology.142(4),727‐733
Goldstein, M.C. & Goodwin, D.S. (2013). Gooseneck barnacles (Lepas spp.) ingest microplasc           
debrisintheNorthPacificSubtropicalGyre.PeerJ.1,p.e184.
Goldstein, M.C., Titmus, A.J. & Ford, M. (2013). Scales of spaal heterogeneity of plasc marine              
debrisintheNortheastPacificOcean.PLoSOne.10.1371/journal.pone.0080020.
Gorokhova, E. (2015). Screening for microplasc parcles in plankton samples: how to integrate            
marine lier assessment into exisng monitoring programs? Marine Pollution Bulletin. 99(1‐2),          
271–275.
Green, D.S. (2016). Effects of microplascs on European flat oysters, Ostrea edulis and their            
associatedbenthiccommunies.EnvironmentalPollution.216,95‐103.
Green, D.S., Boots, B., Sigwart, J., Jiang, S. & Rocha, C. (2016). Effects of convenonal and               
biodegradable microplascs on a marine ecosystem engineer (Arenicola marina) and sediment         
nutrientcycling.EnvironmentalPollution.208,426‐434.
Green, S., Visser, A.W., Titelman, J. & Kiørboe, T. (2003). Escape responses of copepod nauplii in               
theflowfieldofthebluemussel,Mytilusedulis.MarineBiology.142(4),727‐733.
Gutow, L., Eckerlebe, A., Gimenez, L. & Saborowski, R. (2015). Experimental evaluaon of            
seaweeds as vector for microplascs into marine food webs. Environmental Science &           
Technology.50,915–923.
Hammer, S., Nager, R.G., Johnson, P.C.D., Furness, R.W. & Provencher, J.F. (2016). Plasc debris in              
great skua (Stercorarius skua) pellets corresponds to seabird prey species. Marine Pollution          
Bulletin.103,206‐210.
Hara,T.J.(1975).OlfaconinfishProgressinNeurobiology.5(4),271‐335.

Harrison, J.P., Schratzberg, M., Sapp, M. & Osborn, A.M. (2014). Rapid bacterial colonizaon of             
low‐density polyethylene microplascs in coastal sediment microcosms. BMC Microbiology.       
14(1),232.
Hidalgo‐Ruz, V., Gutow, L., Thompson, R.C. & Thiel, M. (2012) Microplascs in the marine             
environment: a review of the methods used for idenficaon and quanficaon.          
EnvironmentalScience&Technology.46,3060‐307.
Holling, C.S. (1959). The components of predaon as revealed by a study of small‐mammal             
predaonoftheEuropeanpinesawfly.TheCanadianEntomologist.91,293‐320.
Hüffer, T., Praetorius, A., Wagner, S., von der Kammer, F. & Hofmann, T. (2017). Microplasc              
exposure assessment in aquac environments: Learning from similaries and differences to          
engineerednanoparcles.EnvironmentalScience&Technology.51(5),2499–2507
Huntley, M.E., Barthel, K.G. & Star, J.L. (1983). Parcle rejecon by Calanus pacificus:           
discriminaonbetweensimilarlysizedparcles.MarineBiology.74,151‐160.
Kaiser, D., Kowalski, N. & Waniek, J.J. (in press). Effects of biofouling on the sinking behavior of                
microplascs.EnvironmentalResearchLetters.
Kautsky, L. & Kautsky, N. (2000). Balc Sea, including Bothnian Sea and Bothnian Bay. In:              
Sheppard, C.R. C. (ed) Seas at the millennium: an environmental evaluaon. Elsevier Science            
Ltd.Chapter8,p1–14.
Koehl M.A.R. & Sckler J.R. (1981). Copepod feeding currents: Food capture at low Reynolds             
number.Limnology&Oceanography.26,1062‐1073.
Koelmans, A.A., Bakir, A., Burton, G.A. & Janssen, C.R. (2016). Microplasc as a vector for              
chemicals in the aquac environment: crical review and model‐supported reinterpretaon of          
empiricalstudies.EnvironmentalScience&Technology.50(7),3315‐3326.
Kiørboe, T., Møhlenberg, F. & Nicolajsen, H. (1982) Ingeson rate and gut clearance in the              
planktonic copepod Centropages hamatus (Liljeborg) in relaon to food concentraon and         
temperature.Ophelia.21,181‐194.
Kooi, M., Van Nes, E.H., Scheffer, M. & Koelmans, A.A. (2017). Ups and downs in the ocean: Effects                 
of biofouling on the vercal transport of microplascs. Environmental Science & Technology.           
51(14),7963–7971doi:10.1021/acs.est.6b04702
Krümmel, E., Macdonald, RW., Kimpe, L.E., Gregory‐Eaves, I., Demers, M., Smol, J.P., Finney, B. &              
Blais,J.M(2003).Deliveryofpollutantsbyspawningsalmon.Nature.425,255‐256
Laist, D. W. (1997). Impacts of marine debris: entanglement of marine life in marine debris              
including a comprehensive list of species with entanglement and ingeson records. In Marine            
Debris(pp.99‐139).SpringerNewYork.
Law, K.L., Morét‐Ferguson, S., Maximenko, N.A.., Proskurowski, G., Peacock, E.E.., Hafner, J. &            
Reddy, C.M. (2010). Plasc Accumulaon in the North Atlanc Subtropical Gyre. Science. 329,            
1185‐1188
Lee, K.W., Shim, W.J., Kwon, O.Y. & Kang, J.H. (2013). Size‐dependent effects of micro polystyrene              
parcles in the marine copepod Tigriopus japonicus. Environmental Science & Technology. 47,         
11278‐1183.

Ling, S.D., Sinclair, M., Levi, C.J., Reeves, S.E. & Edgar, G.J. (2017). Ubiquity of microplascs in               
coastalseafloorsediments.MarinePollutionBulletin.121(1‐2),104‐110.
Lobelle, D. & Cunliffe, M. (2011). Early microbial biofilm formaon on marine plasc debris.             
MarinePollutionBulletin.62(1),197‐200.
Long, M., Moriceau, B., Gallinari, M., Lambert, C., Huvet, A., Raffray, J. & Soudant, P. (2015).               
Interacons between microplascs and phytoplankton aggregates: impact on their respecve         
fates.MarineChemistry.175,39‐46.
Lusher, A.L., McHugh, M. & Thompson, R.C. (2013). Occurrence of microplascs in the            
gastrointesnal tract of pelagic and demersal fish from the English Channel. Marine Pollution            
Bulletin.67(1‐2),94‐99.
Lusher, A.L., Hernandez‐Milian, G., O'Brien, J., Berrow, S., O'Connor, I. & Officer, R. (2015).             
Microplasc and macroplasc ingeson by a deep diving, oceanic cetacean: The True's beaked            
whaleMesoplodonmirus.EnvironmentalPollution.199,185‐191.
Lusher, A.L.., Tirelli, V., O’Connor, I. & Officer, R. (2015). Microplascs in Arcc polar waters: the               
first reported values of parcles in surface and sub‐surface samples. Scientific Reports. 5,           
14947,srep14947.
Lusher, A.L., O’Donnell, C., Officer, R. & O’Connor, I. (2016). Microplasc interacons with North             
Atlancmesopelagicfish.ICESJournalofMarineScience.73(4),1214‐1225.
Lusher, A.L., Welden, N.A., Sobral, P. & Cole, M. (2017). Sampling, isolang and idenfying             
microplascsingestedbyfishandinvertebrates.AnalyticalMethods.9,1346‐1360.
Mathalon, A. & Hill, P. (2014). Microplasc fibers in the interdal ecosystem surrounding Halifax             
Harbor,NovaScoa.MarinePollutionBulletin.81(1),69‐79.
Mato, Y., Isobe. T., Takada, H., Kanehiro, H., Ohtake, C. & Kaminuma, T. (2001). Plasc resin pellets                
as a transport medium for toxic chemicals in the marine environment. Marine Pollution            
Bulletin.35(2),318‐324
Miller, M.E., Kroon, F.J. & Mo, C.A. (2017). Recovering microplascs from marine samples: A             
review of current pracces. Marine Pollution Bulletin. 123(1–2), 6‐18.        
doi.org/10.1016/j.marpolbul.2017.08.058
Moore, S.L., Leecaster, M.K. & Weisberg, S.B. (2001) A comparison of plasc and plankton in the                
northPacificcentralgyre.MarinePollutionBulletin.42,1297‐1300.
Mu, H., Ewald, G., Nilsson, E., Sundin, P. & Wese´n, C. (2004). Fate of chlorinated fay acids in                 
migrang sockeye salmon and their transfer to arcc grayling. Environmental Science &           
Technology.38,5548‐5554.
Munari, C., Infanni, V., Scoponi, M., Rastelli, E., Corinaldesi, C. & Mistri, M. (2017). Microplascs              
in the sediments of Terra Nova Bay (Ross Sea, Antarcca). Marine Pollution Bulletin. 122,             
161–165.
Murray, P.R. & Cowie P.R. (2011). Plasc contaminaon in the decapod crustacean Nephrops            
norvegicus(Linnaeus,1758).MarinePollutionBulletin.62,1207‐1217

NOAA ‐ Naonal Oceanic and Atmospheric Administraon Marine Debris Program (2014). Report           
on the entanglement of marine species in marine debris with an emphasis on species in the               
UnitedStates.SilverSpring,MD.pp.28
Nelms, S.E., Duncan, E.M., Broderick, A.C., Galloway, T.S., Godfrey, M.H., Hamann, M., Lindeque,            
P.K. & Godley, B.J. (2015). Plasc and marine turtles: a review and call for research. ICES Journal                
ofMarineScience:JournalduConseil.73(2),165‐181.
Nygaard, K., Borsheim, K.Y. & Thingstad, T.F. (1988). Grazing rates on bacteria by marine             
heterotrophic microflagellates compared to uptake rates of bacterial‐sized monodisperse        
fluorescentlatexbeads.MarineEcologyProgressSeries.44,159‐165.
Näkki, P., Setälä, O. & Lehniemi, M. (2017). Bioturbaon transports secondary microplascs to            
deeper layers in so marine sediments of the northern Balc Sea. Marine Pollution Bulletin.             
15;119(1):255‐261.doi:10.1016/j.marpolbul.2017.03.065.
Oberbeckmann, S., Loeder, M.G.J., Gerdts, G. & Osborn, M. (2014). Spaal and seasonal variaon             
in diversity and structure of microbial biofilms on marine plascs in Northern European waters.             
FEMSMicrobiologyEcology.90,478–492.
Ogonowski, M., Schür, C., Jarsén, Å. & Gorokhova, E. (2016). The effects of natural and              
anthropogenic microparcles on individual fitness in Daphnia magna. PLoS ONE. 11(5),       
e0155063.
Ogonowski, M., Wenman, D. & Gorokhova, E. (2017). Ingested microplasc is not correlated to             
HOC concentraons in Balc Sea herring. 15th International Conference on Environmental          
ScienceandTechnology.Rhodes,Greece,31Augustto2September2017.
Phuong, N.N., Zalouk‐Vergnoux, A., Poirier, L., Kamari, A., Châtel, A., Mouneyrac, C. & Lagarde, F.              
(2016). Is there any consistency between the microplascs found in the field and those used in               
laboratoryexperiments?EnvironmentalPollution.211,111‐123.
Railo, S. (2017). Microlier in Mytilus trossulus and its environment in the Northern Balc Sea:              
Wastewateraspointsourcepolluon.MScthesis:UniversityofHelsinki,Finland.
Rescigno, M., Urbano, M., Valzasina, B., Francolini, M., Roa, G., Bonasio, R.. &            
Ricciardi‐Castagnoli, P. (2001). Dendric cells express ght juncon proteins and penetrate gut           
epithelialmonolayerstosamplebacteria.NatureImmunology.2(4).
Riisgård, H.U. and Larsen, P.S. (2010). Parcle capture mechanisms in suspension‐feeding          
invertebrates.MarineEcologyProgressSeries,418:255‐293.doi.org/10.3354/meps08755.
Rochman, C.M., Tahir, A., Williams, S.L., Baxa, D.V., Lam, R., Miller, J.T., Teh, F., Werorilangi, S. &                
Teh, S.J. (2015). Anthropogenic debris in seafood: Plasc debris and fibers from texles in fish              
andbivalvessoldforhumanconsumpon.ScientificReports.5,14340.
Rummel, C.D., Jahnke, A., Gorokhova, E., Kühnel, D. & Schmi‐Jansen, M. (2017). The impacts of              
biofilm formaon on the fate and potenal effects of microplasc in the aquac environment.             
EnvironmentalScience&TechnologyLetters,4(7)258–267DOI:10.1021/acs.estle.7b00164
Schuyler, Q., Hardesty, B.D., Wilcox, C. & Townsend, K. (2012). To eat or not to eat? Debris                
selecvitybymarineturtles.PLoSONE.7(7),e40884.

Setälä, O., Sopanen, S., Auo, R. & Erler, K. (2009): Grazing and prey selecon of the calanoid                
copepods Eurytemora affinis and Acartia bifilosa feeding on plankton assemblages        
containingDinophysisspp.BorealEnvironmentResearch.14,837‐849.
Setälä, O., Fleming‐Lehnen, V. & Lehniemi, M. (2014). Ingeson and transfer of microplascs in             
theplanktonicfoodweb.EnvironmentalPollution.185:77‐83.
Setälä, O., Norkko, J., & Lehniemi, M. (2016). Feeding type affects microplasc ingeson in a              
coastalinvertebratecommunity.Marinepollutionbulletin,102(1),95‐101.
Setälä, O., Magnusson, K., Lehniemi, M., & Norén, F. (2016). Distribuon and abundance of             
surface water microlier in the Balc Sea: A comparison of two sampling methods. Marine             
pollutionbulletin,110(1)177‐183.
Sherman, P. & Van Sebille, E. (2016). Modeling marine surface microplasc transport to assess             
opmalremovallocaons.EnvironmentalResearchLetters,.11(1),014006.
Sileo, L., Sievert, P. R., Samuel, M. D., & Fefer, S. I. (1990). Prevalence and characteriscs of plasc                 
ingested by Hawaiian seabirds. In Proceedings of the Second International Conference on           
MarineDebris(665‐681).NOAATechnicalMemoHonolulu.
Solomon, M.E. (1949). The natural control of animal populaons. Journal of Animal Ecology. 18,             
1‐35
Staresinic, N., Farrington, J., Gagosian, R.B., Clifford, C.H. & Hulburt, E.M. (1983). Downward            
transport of parculate maer in the Peru coastal upwelling: Role of the anchoveta, Engraulis             
ringens. In: Suess, E. & Theide, J. (Eds.) Coastal Upwelling: Its Sediment Record. Part A.              
Responses of the Sedimentary Regime to Present Coastal Upwelling. Plenum, New York, pp.            
225–240.
Steer, M., Cole, M., Thompson, R.C. & Lindeque, P.K. (2017). Microplasc ingeson in fish larvae in               
thewesternEnglishChannel.EnvironmentalPollution.226,250‐259.
Sun, X., Li, Q., Zhu, M., Liang, J., Zheng, S. & Zhao, Y. (2017). Ingeson of microplascs by natural                  
zooplankton groups in the northern South China Sea. Marine Pollution Bulletin. 115(1‐2),           
217‐224.
Sussarellu, R., Suquet, M., Thomas, Y., Lambert, C., Fabioux, C., Pernet, M. E. J. & Huvet, A. (2016).                 
Oyster reproducon is affected by exposure to polystyrene microplascs. Proceedings of the           
NationalAcademyofSciencesoftheUnitedStatesofAmerica.113(9),2430–2435.
Syberg, K., Khan, F.R., Selck, H., Palmqvist, A., Banta, G.T., Daley, J., Sano, L. & Duhaime, M.B.                
(2015). Microplascs: addressing ecological risk through lessons learned. Environmental        
Toxicology&Chemistry.34(5),945‐953.
Taylor, M.L., Gwinne, C., Robinson, L.F. & Woodall, L.C. (2016). Plasc microfibre ingeson by            
deep‐seaorganisms.ScientificReports.6,33997.
Tiselius, P., Jonsson, P. R. & Verity, P. G. (1993). A model evaluaon of the impact of food                 
patchiness on foraging strategy and predaon risk in zooplankton. Bulletin of Marine Science.            
53,247‐264.
Tourinho, P.S., Ivar do Sul, J.A. & Fillmann, G. (2010). Is marine debris ingeson sll a problem for                 
thecoastalmarinebiotaofsouthernBrazil?MarinePollutionBulletin.60(3),396‐401.

Turner, J.T. (2002). Zooplankton fecal pellets, marine snow and sinking phytoplankton blooms.           
AquaticMicrobialEcology.27,57‐102
Turner, J.T. (2015). Zooplankton fecal pellets, marine snow, phytodetritus and the ocean’s           
biologicalpump.ProgressinOceanography.130,205‐248.
Van Franeker, J.A., Blaize, C., Danielsen, J., Fairclough, K., Gollan, J., Guse, N., Hansen, P.L.,              
Heubeck, M., Jensen, J.K., Le Guillou, G. & Olsen, B. (2011). Monitoring plasc ingeson by the               
northern fulmar Fulmarus glacialis in the North Sea. Environmental Pollution. 159(10),        
2609‐2615.
Van Franeker, J.A. & Law, K.L. (2015). Seabirds, gyres and global trends in plasc polluon.              
EnvironmentalPollution.203,89‐96.
VanSebille,E.,Wilcox,C.,Lebreton,L.,Maximenko,N.,Hardesty,B.D.,VanFraneker,J.A.,Eriksen,
M.,Siegel,D.,Galgani,F.&Law,K.L.(2015).Aglobalinventoryofsmallfloangplascdebris.
EnvironmentalResearchLetters.10(12),124006.
Vandermeersch, G., Van Cauwenberghe, L., Janssen, C. R., Marques, A., Granby, K., Fait, G. &              
Devriese, L. (2015). A crical view on microplasc quanficaon in aquac organisms.           
EnvironmentalResearch.143,46‐55.
Volkenborn, N., Hedtkamp, S.I.C. Van Beusekom, J.E.E. & Reise, K. (2007). Effects of bioturbaon             
and bioirrigaon by lugworms (Arenicola marina) on physical and chemical sediment         
properes and implicaons for interdal habitat succession. Estuarine and Coastal Shelf          
Science.74,331‐343.
von Moos, N., Burkhardt‐Holm, P. & Köhler, A. (2012). Uptake and effects of microplascs on cells               
and ssue of the blue mussel Mytilus edulis L. aer an experimental exposure. Environmental            
Science&Technology.46(20),11327‐11335.
Waller, C.L., Griffiths, H.J., Waluda, C.M., Thorpe, S.E., Loaiza, I., Moreno, B., Pacherres, C.O. &              
Hughes, K.A. (2017). Microplascs in the Antarcc marine system: An emerging area of            
research.ScienceofTheTotalEnvironment.598,220‐227.
Ward, J.E. & Koch, D.J. (2009). Marine aggregates facilitate ingeson of nanoparcles by            
suspension‐feedingbivalves.MarineEnvironmentalResearch.68,137‐142.
Wa, A.J., Lewis, C., Goodhead, R.M., Becke, S.J., Moger, J., Tyler, C.R. & Galloway, T.S. (2014).               
Uptake and retenon of microplascs by the shore crab Carcinus maenas. Environmental         
Science&Technology.48(15),8823‐8830.
Woodall, L.C., Sanchez‐Vidal, A., Canals, M., Paterson, G.L.J., Coppock, R., Sleight, V., Calafat, A.,             
Rogers, A.D., Narayanaswamy, B.E. & Thompson, R.C. (2014). The deep sea is a major sink for               
microplascdebris.RoyalSocietyOpenScience,1(4),140317.DOI:10.1098/rsos.140317
Wright, S.L., Thompson, R.C. & Galloway T.S. (2013a). The physical impacts of microplascs on             
marineorganisms:areview.EnvironmentalPollution.178,483‐492.
Wright, S.L., Rowe, D., Thompson, R.C. & Galloway, T.S. (2013b). Microplasc ingeson decreases            
energyreservesinmarineworms.CurrentBiology.23(23),1031‐1033.
Ye, S. & Andrady, A.L. (1991). Fouling of floang plasc debris under Biscayne Bay exposure              
condions.MarinePollutionBulletin.22,608–613.

Zeler, E. R., Mincer, T. J. & Amaral‐Zeler, L. A. (2013). Life in the “plassphere”: microbial               
communiesonplascmarinedebris.Environmentalscience&technology,47(13),7137‐7146.
