Martin Täubel

Finnish Institute for Health and Welfare | THL · Department Health Security, Environmental Health Unit

Markers for microbial groups are commonly measured in house dust samples to assess indoor exposure to microbes in studies on asthma and allergy. However, little is known about the sources of different microbes. A better understanding of the nature and origin of microbes present in the immediate environment of human beings is crucial if one wants to...

The indoor air community is witnessing the emergence of a remarkable paradox: Credible lines of evidence are converging to suggest that indoor microbial exposures can be both protective and threatening to human occupants. Beyond the acute infectious diseases from near human contacts, there are increasing suggestions that the built environment can p...

The global increase in the prevalence of asthma has been related to several risk factors; many of them linked to the “westernization” process and the characteristics of the indoor microbial environment during early life may play an important role. Living in moisture damaged homes contributes to the exacerbation and development of asthma. However, l...

Settled airborne dust is used as a surrogate for airborne exposure in studies that explore indoor microbes. In order to determine whether detecting differences in dust environments would depend on the sampler type, we compared different passive, settled dust sampling approaches with respect to displaying qualitative and quantitative aspects of the...

The Environmental Relative Moldiness Index (ERMI) metric was previously developed to quantify mold contamination in United States homes. This study determines the applicability of the ERMI to quantifying mold and moisture damage in Finnish residences. Homes of the LUKAS2 birth cohort in Finland were visually inspected for moisture damage and mold a...

Background Transepidermal water loss (TEWL) has been used to measure skin barrier function and has been associated with atopic dermatitis and allergic diseases in infancy. However, few studies have assessed the association between TEWL and allergic diseases in adolescents. Objective To investigate the association between TEWL and allergic sensitiz...

Background: Conflicting findings exist on the relationship between endotoxin and respiratory health in childhood, and few have considered school exposure, thus impinging comparisons. Using a standardized protocol, we investigated the association between endotoxin levels in classrooms of primary schools and respiratory health in schoolchildren. Meth...

Actinobacteria are abundant in soil and other environmental ecosystems and are also an important part of the human microbiota. Hence, they can also be detected in indoor environments and on building materials, where actinobacterial proliferation on damp materials can indicate moisture damage. The aim of this study was to evaluate the matrix-assiste...

Moisture-damaged buildings are a prominent issue in Finland, but with limited information on damage prevalence, degree of severity and risk factors. This paper analyses 14,996 Finnish detached and semidetached houses that have undergone a standardised moisture assessment of interior spaces and at-risk structures inside the building envelope. Confir...

Early childhood is a critical period for both immune and neural development. and interactions between the immune system and neurons are believed to help regulate synaptic plasticity, which is critical for learning. However, it’s unclear how exposure to microbes within indoor dust might influence brain function in children. To learn more, researcher...

Rationale: Fungal exposure has been associated with predisposing and protective effects on the development of childhood asthma. Objective: To study whether early-life house dust mycobiota composition is associated with the development of asthma. Methods: Mycobiota was determined by amplicon sequencing from 382 dust samples collected from livin...

The existing knowledge on the effect of air cleaners in reducing different indoor impurities and health symptoms in real-life applications is still insufficient. PUHHO study aimed to fill this knowledge gap with a blinded intervention study in 18 primary school classrooms. The study was conducted during 8 weeks with 2 weeks without air cleaner, 3 w...

Bioaerosols are emitted from various sources into the indoor environment and can positively and negatively impact human health. Humans are the major source of bioaerosol emissions indoors, specifically for bacteria. However, efficient sampling to guarantee successful downstream analyses can be challenging due to the relatively low bioaerosol concen...

Background Urban‐related nature exposures are suggested to contribute to the rising prevalence of allergic diseases despite little supporting evidence. Our aim was to evaluate the impact of 12 land cover classes and two greenness indices around homes at birth on the development of doctor‐diagnosed eczema by the age of 2 years, and the influence of...

Background Childhood cognitive development depends on neuroimmune interactions. Immunomodulation by early-life microbial exposure may influence neuropsychological function. In this study, we investigate the association between residential indoor microbiota and cognition and behavior among preschoolers. Results Indoor-settled dust bacterial and fun...

Background: Although children can frequently experience a cough that affects their quality of life, few epidemiological studies have explored cough without a cold during childhood. Objectives: The objective of the study was to describe the latent class trajectories of cough from one to 10 years old and analyse their association with wheezing, at...

The indoors is where many humans spend most of their time, and are strongly exposed to indoor microbiota, which may have multifaceted effects on health. Therefore, a comprehensive understanding of the determinants of indoor microbiota is necessary. We collected dust samples from 295 homes of families with young children in the Helsinki region of Fi...

Background An important ‘window of opportunity’ for early life exposures has been proposed for the development of atopic eczema and asthma. Objective However it is, unknown whether hay fever with a peak incidence around late school age to adolescence is similarly determined very early in life. Methods In the PASTURE birth cohort potentially relev...

Background and Aims Moisture damage increases the risk for respiratory disorders in childhood. Our aim was to determine whether early age residential exposure to inspector‐observed moisture damage or mold is associated with different wheezing phenotypes later in childhood. Methods Building inspections were performed by civil engineers, in a standa...

Little is known about the potential role of indoor plants in shaping the indoor microbiota. Within the ENVIRONAGE birth cohort, we collected settled dust and performed 16S and ITS amplicon sequencing and qPCR measurements to characterize the indoor microbiota, including bacterial and fungal loads and Chao1 richness, Shannon, and Simpson diversity i...

Background Urbanization and biodiversity loss are linked to chronic disorders, in particular allergic diseases. The aim of this scoping review was to provide a synopsis of intervention studies specifically examining the influence of exposure to natural environments on human microbiota as well as immunological markers as suggested interlink between...

Background Multiple health effects are associated with moisture damage in buildings. Studies explaining these associations and cell-level mechanisms behind the observed health effects are urgently called for. Objectives We focused on characterizing gene expression in human airway epithelium after exposure to indoor air particulate matter (PM) samp...

Moisture-damaged buildings are associated with respiratory symptoms and underlying diseases among building occupants, but the causative agent(s) remain a mystery. We first identified specific fungal and bacterial taxa in classrooms with moisture damage in Finnish and Dutch primary schools. We then investigated associations of the identified moistur...

Exposure to farm environment has been shown to both protect from allergic diseases and increase the risk of respiratory syndromes. Mechanisms have been previously investigated by using farm dust extracts or specific components of dust. The use of authentic farm dust would better reflect the natural exposure. The aim of our study was to highlight th...

Background: The influence of outdoor green space on microbial communities indoors has scarcely been investigated. Here, we study the associations between nearby residential green space and residential indoor microbiota. Methods: We collected settled dust from 176 living rooms of participants of the ENVIRONAGE birth cohort. We performed 16S and I...

Living with dogs appears to protect against allergic diseases and airway infections, an effect possibly linked with immunomodulation by microbial exposures associated with dogs. The aim of this study was to characterize the influence of dog ownership on house dust microbiota composition. The bacterial and fungal microbiota was characterized with Il...

Background. Microbial exposures in early childhood direct the development of the immune system and their diversity may influence the risk of allergy development. We aimed to determine whether the indoor microbial diversity at early-life is associated with the development of allergic rhinitis and inhalant atopy. Methods. The study population include...

Carpet dust contains microbial and chemical material that can impact early childhood health. Infants may be exposed to greater quantities of resuspended dust, given their close proximity to floor surfaces. Chamber experiments with a robotic infant were integrated with a material balance model to provide new fundamental insights into the size-depend...

This commentary is intended to provide a research roadmap for utilizing recent chemical and molecular-biological technological advances for addressing dampness and mold in buildings. The perspective is unique in that both the mold industry practitioners and academic researchers drive the questions. Research needs were derived from a 2018 internatio...

Substantial knowledge is available on the association of the indoor school environment and its effect among schoolchildren. In the same context, the SINPHONIE (School indoor pollution and health: Observatory network in Europe) conducted a study to collect data and determine the distribution of several indoor air pollutants (IAPs), physical and ther...

In vitro models mimicking the human respiratory system are essential when investigating the toxicological effects of inhaled indoor air particulate matter (PM). We present a pulmonary cell culture model for studying indoor air PM toxicity. We exposed normal human bronchial epithelial cells, grown on semi-permeable cell culture membranes, to four do...

This study evaluates the association between indoor microbial diversity early in life and hyperactivity/inattention symptoms in children at ages 10 and 15 years.A random sample enriched with subjects with hyperactivity/inattention at age 15 years was selected from the German LISA birth cohort. Bedroom floor dust was collected at age 3 months and 4...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Background: Early-life indoor bacterial exposure is associated with the risk of asthma, but the roles of specific bacterial genera are poorly understood. Objective: We sought to determine whether individual bacterial genera in indoor microbiota predict the development of asthma. Methods: Dust samples from living rooms were collected at 2 month...

Background: Eukaryotes are ubiquitous in natural environments such as soil and freshwater. Little is known of their presence in drinking water distribution systems (DWDSs) or of the environmental conditions that affect their activity and survival. Methods: Eukaryotes were characterized by Illumina high-throughput sequencing targeting 18S rRNA ge...

Asthma prevalence has increased in epidemic proportions with urbanization, but growing up on traditional farms offers protection even today¹. The asthma-protective effect of farms appears to be associated with rich home dust microbiota2,3, which could be used to model a health-promoting indoor microbiome. Here we show by modeling differences in hou...

Online read-only access: https://rdcu.be/bG4oH

We assessed 45 multifamily buildings (240 apartments) from Finland and 20 from (96 apartments) Lithuania, out of which 37 buildings in Finland and 15 buildings in Lithuania underwent energy retrofits. Building characteristics, retrofit activities, and energy consumption data were collected, and indoor air quality (IAQ) parameters, including carbon...

Exposure to moisture‐damaged indoor environments is associated with adverse respiratory health effects, but responsible factors remain unidentified. In order to explore possible mechanisms behind these effects, the oxidative capacity and haemolytic activity of settled dust samples (n=25) collected from moisture‐damaged and non‐damaged schools in Sp...

Background: Studies conducted in farm environments suggest that diverse microbial exposure promotes children's lung health. The underlying mechanisms are unclear and the development of asthma-preventive strategies has been delayed. More comprehensive investigation of the environment-induced immunoregulation is required for better understanding of...

Different types of house dust samples are widely used as surrogates of airborne inhalation exposure in studies assessing health effects of indoor microbes. Here we studied—in a quantitative assessment—the representativeness of different house dust samples of indoor air (IA) and investigated seasonality and reproducibility of indoor samples. Microbi...

Upper and lower respiratory symptoms and asthma are adverse health effects associated with moisture‐damaged buildings. Quantitative measures to detect adverse health effects related to exposure to dampness and mold are needed. Here, we investigate differences in gene expression between occupants of moisture‐damaged and reference buildings. Moisture...

Background/aim The immune system and gut microbiota may play a role in the cognitive development. The home microbiota are a source of microbial exposure affecting immunological and maybe gut microbiota development. Thus, it may contribute to cognitive development. Here, we assess the association between early life home dust microbial diversity and...

Background Floor dust is commonly used for microbial determinations in epidemiological studies to estimate early-life indoor microbial exposures. Resuspension of floor dust and its impact on infant microbial exposure is, however, little explored. The aim of our study was to investigate how floor dust resuspension induced by an infant’s crawling mot...

Both protective and adverse effects of indoor microbial exposure on asthma have been reported, but mostly in children. To date, no study in adults has used non-targeted methods for detection of indoor bacteria followed by quantitative confirmation. A cross-sectional study of 198 asthmatic and 199 controls was conducted within the European Community...

Human-induced resuspension of floor dust is a dynamic process that can serve as a major indoor source of biological particulate matter (bioPM). Inhalation exposure to the microbial and allergenic content of indoor dust is associated with adverse and protective health effects. This study evaluates infant and adult inhalation exposures and respirator...

There is no commonly approved approach to detect and quantify the health relevant microbial exposure in moisture damaged buildings. In 39 single-family homes with severe moisture damage, we studied whether concentrations of viable microbes in building material samples are associated with health among 71 adults and 68 children, assessed with symptom...

Background: The limited understanding of microbial characteristics in moisture-damaged buildings impedes efforts to clarify which adverse health effects in the occupants are associated with the damage and to develop effective building intervention strategies. The objectives of this current study were (i) to characterize fungal and bacterial microb...

The quality of indoor air – and that including the microbial quality – in schools and daycare centers is of crucial importance to pupils’ and teachers’ health. This is because of the extended periods of exposure daily and during life-time, and the vulnerability of in particular pupils to air contaminants due to their maturing physiology and high in...

The challenge of fungal measurements in indoor environments is complex. Almost all studies that have used several methods for the assessment of fungal exposure have only observed moderate or weak correlation between them. These variations can be explained by the fungal life cycle with differences in spore release and the variation in the characteri...

This book intends to provide information about detection and health effects due to bacteria, fungi and viruses in indoor environments. The book will cover also information about preventive and protective measures to avoid health-hazardous. Case studies will be also addressed to enrich the book with the expertise of each invited author. The book als...

Background: Microbial exposures in homes of asthmatic adults have been rarely investigated; specificities and implications for respiratory health are not well understood. Objective: The objectives of this study were to investigate associations of microbial levels with asthma status, asthma symptoms, bronchial hyperresponsiveness (BHR), and atopy...

Evidence is accumulating that indoor dampness and mold are associated with the development of asthma. The underlying mechanisms remain unknown. New Zealand has high rates of both asthma and indoor mold and is ideally placed to investigate this. We conducted an incident case control study involving 150 children with new-onset wheeze, aged between 1...

Moisture-damaged indoor environments are thought to increase the toxicity of indoor air particulate matter (PM), indicating that a toxicological assay could be used as a method for recognizing buildings with indoor air problems. We aimed to test if our approach of analyzing the toxicity of actively collected indoor air PM in vitro differentiates mo...

This review summarizes the current knowledge regarding the occurrence of mycotoxins in indoor environments, considering residential homes, schools, offices, and other public buildings. We provide an overview of studies that report on the detection of mycotoxins and fungal secondary metabolites in actual indoor sample materials, but do not consider...

Fungal growth on indoor surfaces can decay building materials and release hazardous substances that affect indoor air quality. Despite the numerous methods available for growth determination, there is no commonly accepted standard. The goal of this study was to compare five different assay methods for the measurement of fungal growth: cultivation,...

There is a need for toxicity tests capable of recognizing indoor environments with compromised air quality, especially in the context of moisture damage. One of the key issues is sampling, which should both provide meaningful material for analyses and fulfill requirements imposed by practitioners using toxicity tests for health risk assessment. We...

The objective of this work was to investigate the impact of a baby crawling and a person walking over a carpet on the resuspension of particles, focussing on the implications for infant inhalation exposure to microbes. Full-scale chamber measurements with a mechanical crawling infant and a person walking were conducted. We observed that when determ...

The study aimed to determine how well different house dust sample types represent the microbial content of indoor air, and also considered aspects of reproducibility of the assessment. Microbial exposure was measured five times over one year in four rural and five urban homes. Six different sampling methods for indoor air and house dust were used....

Objectives: We investigated the effect of weekends and school holidays on the daily frequency and severity of respiratory and other symptoms among children attending schools with (index) or without (reference) moisture damage in Spain, the Netherlands and Finland. Methods: Throughout one year, parents of 419 children with a respiratory condition...

We welcome the opportunity to respond to the concerns of Dr Wise1 from the American Chemistry Council, regarding our report on the association between childhood infections and use of bleach at home.2 Dr Wise expresses disappointment with ‘design flaws’ and ‘the speculative nature of our conclusions’. We do not agree that our study was badly design...

Indoor exposure to microbes and their structural and metabolic compounds is notoriously complex. In order to study proinflammatory interactions between the multiple microbial agents, macrophages derived from human THP-1 monocytic cells were exposed to several concentrations of microbial toxins alone (emodin, enniatin B, physcion, sterigmatocystin,...

The Sloan Symposium, “Microbiology of the Indoor Environment,” was held to facilitate dialog on biological research between scientists and practitioners in the field which was complementary to the adjoining activities of the ISIAQ Healthy Buildings Europe conference, Eindhoven, Netherlands, on 20–21 May 2015. Multi-media archives of these special a...

Exposure to indoor air in moisture damaged buildings is associated with deteriorating respiratory health, assumedly due to emissions from microbial growth and wet building materials. Previous studies of toxicological effects of mouldy house microbes have indicated that inflammation and cell death are important mechanisms. Aiming to gain further ins...

This report includes a summary of existing policies on providing healthy environments in schools and kindergartens, an overview of environmental risk factors in schools, information on design, methods and results of selected recently conducted exposure assessment surveys and a summary of pupils’ exposures to major environmental factors, such as sel...

The increase in prevalence of asthma and atopic diseases in Western countries has been linked to aspects of microbial exposure patterns of people. It remains unclear which microbial aspects contribute to the protective farm effect. The objective of this study was to identify bacterial groups associated with prevalence of asthma and atopy, and to qu...

Aiming to identify factors causing the adverse health effects associated with moisture damaged indoor environments, we analyzed immunotoxicological potential of settled dust from moisture damaged and reference schools in relation to their microbiological composition. Mouse RAW264.7 macrophages were exposed to settled dust samples (n= 25) collected...

Dampness and mould exposure have been repeatedly associated with respiratory health. However, less is known about the specific agents provoking or arresting health effects in adult populations. We aimed to assess predictors of microbial agents in mattress dust throughout Europe and to investigate associations between microbial exposures, home chara...

To report the effects of bleach use at home on the frequency of infections in 9102 school-age children participating in the HITEA project. Parents of pupils aged 6-12 years from schools in Barcelona province (Spain), Utrecht province (the Netherlands) and Eastern and Central Finland were administered a questionnaire including questions on the frequ...

We aimed to characterize the presence of microbial secondary metabolites in homes and their association with moisture damage, mold and asthma development. Living room floor dust was analyzed by LC-MS/MS for 333 secondary metabolites from 93 homes of one year old children. Moisture damage was present in 15 living rooms. At 6 years, 8 children had ac...