Environmental Chemical Exposures Research Articles

Environmental exposure during pregnancy and the risk of childhood allergic diseases.

Allergic diseases are one of the most common and important diseases that can exert hazardous effects on children's health. The prevalence of allergic diseases in childhood is gradually increasing all over the world in recent decades. Known causes of these diseases include anomalous immune responses and allergic inflammatory reactions, but the causes of allergic diseases in childhood are complex. PubMed, Cochrane Library, Embase and Web of Science were searched for articles focusing on environmental exposure during pregnancy and the risk of childhood allergic diseases, including asthma and atopic dermatitis, and the possible underlying mechanism. In terms of environmental factors, allergic diseases in childhood are closely related to environmental chemical exposure during pregnancy, including bisphenols, phthalates acid esters, perfluorochemicals, polybrominated diphenyl ethers, and polychlorinated biphenyls. However, allergic diseases in childhood are also closely associated with maternal dietary nutrition, maternal intake of drugs, such as acetylsalicylic acid (aspirin), paracetamol and antibiotics, and maternal lifestyle. Several harmful environmental factors during pregnancy can result in the interruption of the function of helper T cells (Th1/Th2), cytokines and immunoglobulins and may activate allergic reactions, which can lead to allergic diseases during childhood.

Association of trace elements abnormalities with thyroid dysfunction.

The metabolic pathways can be affected by dysregulation in thyroid hormone levels which in turn can arise from environmental chemical exposure. This study investigated the association of selected trace elements with thyroid disorders in a Saudi population. Urine samples collected from 100 participants (50 thyroid disorder patients and 50 controls) were analyzed to determine trace elements using inductively coupled plasma-mass spectrometer. Non-parametric Mann-Whitney Test, were used to examine the association between socio-demographic as well as clinical characteristics of thyroid profile levels (T3, T4 and TSH) and urinary trace element concentrations. Urine from patients with thyroid disorders had significantly higher concentrations of Ni, Cu, and Cd (p-values <0.0005). In contrast, urinary Cr and Zn (p-values <0.013 and 0.005) were low in thyroid patients compared to the control. First study to report urinary trace element levels showed a possible link between thyroid disorders and trace element exposure which reflect the environmental pollution..

A geospatial modeling approach to quantifying risk of exposure to environmental chemical mixtures via a common molecular initiating event

BACKGROUND AND AIM: The exposome, a measure of all chemical exposures experienced through a lifetime, plays an important role in human health outcomes. Thus, identifying and quantifying lifetime exposure to chemicals present in the environment is important for risk assessment. Linking health outcomes to environmental chemicals exposures is challenging, as real-world exposures involve multiple chemicals and unresolved spatial and temporal distributions. To address these challenges, we propose a geospatially resolved biological target-based risk assessment for exposure to chemical mixtures. This approach models the geospatial distribution of environmental chemicals based on common activation of toxicological adverse outcome pathways (AOPs) as indicated by Tox21 high throughput assays. METHODS: We exemplify this with a USA-wide proof-of-concept that quantifies the predicted geospatial likelihood of thyroid peroxidase (TPO) inhibition. This enzyme is necessary for producing the thyroid hormone T3 and T4, and inhibition has been associated with decreased cognitive function. First, environmental chemicals were identified that both 1) inhibit TPO based on Tox21 data, and 2) were measured by the USGS and EPA in environmental samples (surface water). Next, the geospatial chemical distributions were modeled with combined land-use regression and Gaussian process models. The individual chemical exposure surfaces can be combined into an aggregate risk surface using an unweighted approach or weighted by chemical potency from the toxicological assay concentration-response data. RESULTS:Maps of the aggregate risk surface will identify regions where thyroid peroxidase inhibition is more likely based on combined environmental chemical exposures and chemical potency. CONCLUSIONS:This work will help advance risk assessment methods by providing a method for assessing the geospatial risk of exposure to environmental chemical mixtures and identifying regions with a higher cumulative risk of activating the selected molecular pathways, which may lead to adverse health outcomes. KEYWORDS: Mixtures, External exposome, Exposure assessment-general, risk assessment, Spatial statistics, big data

Parental Preconception and Prenatal Environmental Exposures and Child Neurobehavioral Outcomes

BACKGROUND AND AIM: There are limited studies quantifying the effects of paternal and maternal preconception environmental exposures on children’s health. The Preconception Environmental exposure And Childhood health Effects (PEACE) Study includes children (age 6-13 years) who were born to couples in the Environment and Reproductive Health (EARTH) Study and aims to determine the extent to which maternal and paternal preconception phthalate exposures are associated with neurobehavioral outcomes. METHODS: The PEACE study began in 2019 and is ongoing. A total of 478 eligible children (includes multiples) were born to 451 mothers who participated in the EARTH study (2005-2017). Study staff collected multiple maternal and paternal preconception urine samples before pregnancy and prenatal maternal urine samples during each trimester of pregnancy. We quantified 10 urinary phthalate metabolites in these samples. Children’s behavior, executive function, and reciprocal social behaviors are being assessed via parent-report using the Behavior Assessment System for Children-3 (BASC-3), Behavior Rating Inventory of Executive Function (BRIEF), and Social Responsiveness Scale-2 (SRS-2), respectively. Trained staff collected additional information about diet, sleep, physical activity, product use, and COVID-19 stress. RESULTS:As of March 2021, we enrolled 95 mothers, 57 fathers, and 120 children in the PEACE Study who completed visits either in person or virtually. Of children who completed the study, 64 (53%) were boys and 97 (81%) were White. Mean BASC-3 total behavior problem scores were 48.7 (SD: 7.6). Ten percent of children had scores indicative of being at-risk for behavioral problems (T-score60). Average BRIEF and SRS-2 scores were 48.2 (SD: 9.5) and 46.9 (SD:6.1), respectively. CONCLUSIONS:The PEACE Study will provide new information about the potential impact of parental preconception environmental chemical exposures on children’s health. In addition, the PEACE study will be able to leverage the rich data repository that includes parental chemical, built environment, and dietary exposures. KEYWORDS: Children's environmental health, Neurodevelopmental outcomes, Phthalates, Male, Chemical exposures, Endocrine disrupting chemicals, Female

Mixture effects of prenatal exposure to per- and polyfluoroalkyl substances and polybrominated diphenyl ethers on maternal and newborn telomere length

BACKGROUND AND AIM: Per- and polyfluoroalkyl substances (PFAS) and polybrominated diphenyl ethers (PBDEs) are endocrine disrupting chemicals associated with reproductive toxicity and adverse health outcomes, including certain cancers. PFAS and PBDEs may affect health through alternations in telomere length. We examined joint associations between prenatal exposure to PFAS, PBDEs, and maternal and newborn telomere length using mixture analyses, to characterize effects of cumulative environmental chemical exposures. METHODS: Study participants were enrolled in the Chemicals in Our Bodies study, a demographically diverse cohort of pregnant women and children in San Francisco, CA. Seven PFAS (ng/mL) and four PBDEs (ng/g lipid) were measured in second trimester maternal serum. Telomere length (T/S ratio) was measured in delivery cord blood of 292 newborns and 110 second trimester maternal whole blood samples. Quantile g-computation was used to assess the joint associations between groups of PFAS and PBDEs and newborn and maternal telomere length. Groups considered were: (1) all PFAS and PBDEs combined, (2) PFAS, and (3) PBDEs. Maternal and newborn telomere length were modeled as separate outcomes. RESULTS:T/S ratios in newborn cord and maternal whole blood were moderately correlated (Spearman ρ= 0.31). In mixtures analyses, a simultaneous one quartile increase in all PFAS and PBDEs was associated with a small increase in newborn (mean change per quartile increase =0.03, 95% confidence interval [CI]=-0.03, 0.08) and maternal telomere length (mean change per quartile increase =0.03 (95% CI=-0.03, 0.09). When restricted to maternal-fetal paired samples (N=76), increasing all PFAS and PBDEs combined was associated with a strong, positive increase in newborn telomere length (mean change per quartile increase=0.16, 95% CI=0.03, 0.28). These associations were primarily driven by PFAS (mean change per quartile increase= 0.11 [95% CI=0.01, 0.22]). CONCLUSIONS:Our findings show that PFAS and PBDEs may be positively associated with newborn telomere length. KEYWORDS: Per- and poly-fluoroalkyl substances, Polybrominated diphenyl ethers, telomere, exposure mixture

Dietary intake and blood concentrations of folate and folic acid in relation to serum per- and polyfluoroalkyl substances (PFAS) concentrations

BACKGROUND AND AIM: Folate may counteract the effects of environmental chemical exposures. This study aimed to explore the associations of dietary folate and folic acid intake with serum concentrations of per- and polyfluoroalkyl substances (PFAS). METHODS: We included 505 children (aged 3-11), 345 adolescents (aged 12-19), and 1,458 adults (aged 20-80) in the National Health and Nutrition Examination Study (NHANES), 2013 - 2014 cycle. Dietary intake of folate and folic acid in food and supplementation were evaluated by dietary recall in the last 24h and 30 days, respectively. Biomarker concentrations of folate and folic acid in serum and folate in red blood cells were also assessed. We examined serum perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS). Multivariable regression models were used to assess change in log2-transformed PFAS concentrations in relation to dietary intake and folate and folic acid biomarkers, adjusting for covariates. RESULTS:Children’s dietary supplement intake of folic acid was negatively associated with PFOA, PFOS and PFNA concentrations (for example, PFNA: -13%; 95%CI: -29%, 0.07%). In adolescents, significant negative associations were found for folate in red blood cells and all four PFAS concentrations (for example, PFNA: -25%; 95%CI: -43%, -1%); total serum folate concentration and PFNA; and dietary intake of folate in food and PFOA and PFHxS concentrations. In adults, significant negative associations were found for dietary supplement intake of folic acid and serum concentrations of PFOA, PFOS and PFNA (PFNA: -10%; 95%CI: -18%, -2%); folate concentrations in red blood cells and all four PFAS concentrations; as well as serum folic acid and total folate concentrations and PFOA, PFOS and PFNA. CONCLUSIONS:Dietary intake and biomarkers of folate and folic acid were negatively associated with select PFAS concentrations in the U.S. population. These findings may have important implications for reducing PFAS body burden. KEYWORDS: PFAS, folate, folic acid, exposure reduction

Circular RNA circ_Cabin1 promotes DNA damage in multiple mouse organs via inhibition of non-homologous end-joining repair upon PM2.5 exposure.

Fine particulate matter (PM2.5) has been shown to induce DNA damage. Circular RNAs (circRNAs) have been implicated in various disease processes related to environmental chemical exposure. However, the role of circRNAs in the regulation of DNA damage response (DDR) after PM2.5 exposure remains unclear. In this study, male ICR mice were exposed to PM2.5 at a daily mean concentration of 382.18μg/m3 for 3months in an enriched-ambient PM2.5 exposure system in Shijiazhuang, China, and PM2.5 collected form Shijiazhuang was applied to RAW264.7 cells at 100µg/mL for 48h. The results indicated that exposure to PM2.5 induced histopathological changes and DNA damage in the lung, kidney and spleen of male ICR mice, and led to decreased cell viability, increased LDH activity and DNA damage in RAW264.7 cells. Furthermore, circ_Cabin1 expression was significantly upregulated in multiple mouse organs as well as in RAW264.7 cells upon exposure to PM2.5. PM2.5 exposure also resulted in impairment of non-homologous end joining (NHEJ) repair via the downregulation of Lig4 or Dclre1c expression in vivo and in vitro. Importantly, circ_Cabin1 promoted PM2.5-induced DNA damage via inhibiting of NHEJ repair. Moreover, the expression of circ_Cabin1 and Lig4 or Dclre1c was strongly correlated in multiple mouse organs, as well as in the blood. In summary, our study provides a new perspective on circRNAs in the regulation of DDR after environmental chemical exposure.

Molecular mechanisms of environmental toxin cadmium at the feto-maternal interface investigated using an organ-on-chip (FMi-OOC) model

Human labor is associated with feto-maternal-derived signals that coordinate to initiate delivery. Exposure to environmental chemicals can prematurely trigger labor-initiating signals at the feto-maternal interface (FMi: decidua, amniochorion), leading to spontaneous preterm birth (PTB). Testing the association between environmental chemical exposure and PTB is difficult due to many limitations in vivo or in vitro. Physiological organ-on-chips (OOCs) are potential alternatives for studying mechanisms leading to PTB. The presented study tested the effect of maternal exposure to cadmium (Cd), an environmental toxin, using the FMi-OOC that incorporates maternal decidua cells and three different fetal cells (chorion, amnion mesenchymal, and amnion epithelial cells). Cd transport through the FMi and its impact on cell cycle, cell death, and inflammation were analyzed. Cd treatment resulted in significant cell death and a pro-inflammatory environment in the maternal decidua, but had minimal effect on the fetal chorion cells, and no effect in the fetal amnion cells compared to controls. The maternal response, but lack of fetal response, indicates that Cd-mediated adverse effects originate from maternal pathophysiology rather than fetal-derived triggers of preterm labor. This study demonstrates that the FMi-OOC can indeed predict the response of FMi upon exposure to chemicals, opening the possibility for using OOC models for environmental toxin screens.

Looking for Proof in the Wrong Generation?

The article in this issue "Grandmaternal Perinatal Serum DDT in Relation to Granddaughter Early Menarche and Adult Obesity: Three Generations in the Child Health and Development Studies Cohort," by Cirillo and colleagues, is the first to report multigenerational health effects in granddaughters stemming from early life exposures to the pesticide o,p'-DDT in grandmothers. Health effects associated with F0 environmental chemical exposures in multiple generations have been reported in rodent studies, but not in humans. The striking finding in this body of work by Cohn and her colleagues is that the granddaughters were never directly exposed to o,p'-DDT-only their grandmothers were, potentially when they were adolescents. The increased rise of obesity and early menarche due to o,p'-DDT exposures generations earlier may help explain why it has been so difficult to describe environmental contributors of disease. Have we been looking for exposures in the wrong generation?See related article by Cirillo et al., p. 1480.

Concentrations of tetanus and diphtheria antibodies in vaccinated Greenlandic children aged 7–12 years exposed to marine pollutants, a cross sectional study

Previous studies have shown immunotoxic effects of environmental chemicals, and the European Food Safety Authority (EFSA) recently identified a need for more studies on PFAS immunotoxicity in different populations. In the Arctic, populations are exposed to several environmental chemicals through marine diet, and the objective of this study was therefore to examine the association between Greenlandic children's exposure to major environmental chemicals and their concentrations of diphtheria and tetanus vaccine antibodies after vaccination. The study includes cross-sectional data from Greenlandic children aged 7–12 years examined during 2012–2015. A total of 338 children were eligible for the study, and 175 of these had available vaccination records. A parent or guardian participated in a structured interview, and a blood sample from the child was analyzed for specific antibodies against diphtheria and tetanus as well as perfluoroalkyl substances (PFASs), polychlorinated biphenyls (PCBs) and total mercury. Furthermore, for a subgroup, blood samples from pregnancy were available and analyzed for environmental contaminants. The associations between the environmental exposures and antibody concentrations and odds of having antibody concentrations below the protective level were examined in linear and logistic regression models. In crude analyses, elevated concentrations of some of the contaminants were associated with higher concentrations of diphtheria and tetanus antibodies, but the associations were reversed when adjusting for area of residence, and duration of being breastfed and including children with a known vaccination date only. Each 1 ng/mL increase in serum concentrations of perfluorohexane sulfonic acid (PFHxS) and perfluorooctane sulfonic acid (PFOS) was associated with decreases of 78 % (95 % CI: 25–94 %) and 9 % (95 % CI: 2–16 %), respectively, in diphtheria antibody concentrations. Exposure to PCBs and all PFASs was associated with markedly increased odds of having diphtheria antibody concentrations below the protective level. For each 1 ng/mL increase in serum concentrations of PFHxS, PFOS, perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA), odds of not having protective levels of diphtheria antibodies were increased 6.44 times (95 % CI: 1.51–27.36), 1.14 times (95 % CI: 1.04–1.26), 1.96 times (95 % CI: 1.07–3.60), and 5.08 times (95 % CI: 1.32–19.51, respectively. No consistent associations were seen between maternal contaminant concentrations and vaccine antibody concentrations. In conclusion, we found that increased exposure to environmental chemicals among children in this Arctic population were associated with a decrease in post-vaccination antibody concentrations and with increased odds of not being protected against diphtheria despite appropriate vaccination. These findings emphasize the risk of environmental chemical exposures also in this Arctic population.

Application of land use regression modelling to describe atmospheric levels of semivolatile organic compounds on a national scale

Despite the success of passive sampler-based monitoring networks in capturing global atmospheric distributions of semivolatile organic compounds (SVOCs), their limited spatial resolution remains a challenge. Adequate spatial coverage is necessary to better characterize concentration gradients, identify point sources, estimate human exposure, and evaluate the effectiveness of chemical regulations such as the Stockholm Convention on Persistent Organic Pollutants. Land use regression (LUR) modelling can be used to integrate land use characteristics and other predictor variables (industrial emissions, traffic intensity, demographics, etc.) to describe or predict the distribution of air concentrations at unmeasured locations across a region or country. While LUR models are frequently applied to data-rich conventional air pollutants such as particulate matter, ozone, and nitrogen oxides, they are rarely applied to SVOCs.The MONET passive air sampling network (RECETOX, Masaryk University) continuously measures atmospheric SVOC levels across Czechia in monthly intervals. Using monitoring data from 29 MONET sites over a two-year period (2015–2017) and a variety of predictor variables, we developed LUR models to describe atmospheric levels and identify sources of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDT across the country. Strong and statistically significant (R2 > 0.6; p < 0.05) models were derived for PAH and PCB levels on a national scale. The PAH model retained three predictor variables – heating emissions represented by domestic fuel consumption, industrial PAH point sources, and the hill:valley index, a measure of site topography. The PCB model retained two predictor variables – site elevation, and secondary sources of PCBs represented by soil concentrations. These models were then applied to Czechia as a whole, highlighting the spatial variability of atmospheric SVOC levels, and providing a tool that can be used for further optimization of sampling network design, as well as evaluating potential human and environmental chemical exposures.

Reproductive Health Risks Associated with Occupational and Environmental Exposure to Pesticides.

A marked reduction in fertility and an increase in adverse reproductive outcomes during the last few decades have been associated with occupational and environmental chemical exposures. Exposure to different types of pesticides may increase the risks of chronic diseases, such as diabetes, cancer, and neurodegenerative disease, but also of reduced fertility and birth defects. Both occupational and environmental exposures to pesticides are important, as many are endocrine disruptors, which means that even very low-dose exposure levels may have measurable biological effects. The aim of this review was to summarize the knowledge collected between 2000 and 2020, to highlight new findings, and to further interpret the mechanisms that may associate pesticides with infertility, abnormal sexual maturation, and pregnancy complications associated with occupational, environmental and transplacental exposures. A summary of current pesticide production and usage legislation is also included in order to elucidate the potential impact on exposure profile differences between countries, which may inform prevention measures. Recommendations for the medical surveillance of occupationally exposed populations, which should be facilitated by the biomonitoring of reduced fertility, is also discussed.

Trends in environmental chemical concentrations in the Canadian population: Biomonitoring data from the Canadian Health Measures Survey 2007–2017

Ten years of nationally representative biomonitoring data collected between 2007 and 2017 are available from the Canadian Health Measures Survey (CHMS). These data establish baseline environmental chemical concentrations in the general population. Here we sought to evaluate temporal trends in environmental chemical exposures in the Canadian population by quantifying changes in biomarker concentrations measured in the first five two-year cycles of the CHMS. We identified 39 chemicals that were measured in blood or urine in at least three cycles and had detection rates over 50% in the Canadian population. We calculated geometric mean concentrations for each cycle using the survey weights provided. We then conducted analyses of variance to test for linear trends over all cycles. We also calculated the percent difference in geometric means between the first and most recent cycle measured. Of the 39 chemicals examined, we found statistically significant trends across cycles for 21 chemicals. Trends were decreasing for 19 chemicals from diverse chemical groups, including metals and trace elements, phenols and parabens, organophosphate pesticides, per- and polyfluoroalkyl substances, and plasticizers. Significant reductions in chemical concentrations included di-2-ethylhexyl phthalate (DEHP; 75% decrease), perfluorooctane sulfate (PFOS; 61% decrease), perfluorooctanoic acid (PFOA; 58% decrease), dimethylphosphate (DMP; 40% decrease), lead (33% decrease), and bisphenol A (BPA; 32% decrease). Trends were increasing for two pyrethroid pesticide metabolites, including a 110% increase between 2007 and 2017 for 3-phenoxybenzoic acid (3-PBA). No significant trends were observed for the remaining 18 chemicals that included arsenic, mercury, fluoride, acrylamide, volatile organic compounds, and polycyclic aromatic hydrocarbons. National biomonitoring data indicate that concentrations, and therefore exposures, have decreased for many priority chemicals in the Canadian population. Concentrations for other chemical groups have not changed or have increased, although average concentrations remain below thresholds of concern derived from human exposure guidance values. Continued collection of national biomonitoring data is necessary to monitor trends in exposures over time.

Cohort profile: Understanding Pregnancy Signals and Infant Development (UPSIDE): a pregnancy cohort study on prenatal exposure mechanisms for child health

PurposeExtensive research suggests that maternal prenatal distress is reliably related to perinatal and child health outcomes—which may persist into adulthood. However, basic questions remain regarding mechanisms involved. To better understand...

Early-life environmental exposure determinants of child behavior in Europe: A longitudinal, population-based study

BackgroundEnvironmental exposures in early life influence the development of behavioral outcomes in children, but research has not considered multiple exposures. We therefore aimed to investigate the impact of a broad spectrum of pre- and postnatal environmental exposures on child behavior. Methods and findingsWe used data from the HELIX (Human Early Life Exposome) project, which was based on six longitudinal population-based birth cohorts in Europe. At 6–11 years, children underwent a follow-up to characterize their exposures and assess behavioral problems. We measured 88 prenatal and 123 childhood environmental factors, including outdoor, indoor, chemical, lifestyle and social exposures. Parent-reported behavioral problems included (1) internalizing, (2) externalizing scores, using the child behavior checklist (CBCL), and (3) the Conner’s Attention Deficit Hyperactivity Disorder (ADHD) index, all outcomes being discrete raw counts. We applied LASSO penalized negative binomial regression models to identify which exposures were associated with the outcomes, while adjusting for co-exposures. In the 1287 children (mean age 8.0 years), 7.3% had a neuropsychiatric medical diagnosis according to parent’s reports. During pregnancy, smoking and car traffic showing the strongest associations (e.g. smoking with ADHD index, aMR:1.31 [1.09; 1.59]) among the 13 exposures selected by LASSO, for at least one of the outcomes. During childhood, longer sleep duration, healthy diet and higher family social capital were associated with reduced scores whereas higher exposure to lead, copper, indoor air pollution, unhealthy diet were associated with increased scores. Unexpected decreases in behavioral scores were found with polychlorinated biphenyls (PCBs) and organophosphate (OP) pesticides. ConclusionsOur systematic exposome approach identified several environmental contaminants and healthy lifestyle habits that may influence behavioral problems in children. Modifying environmental exposures early in life may limit lifetime mental health risk.

23255 Devices Engineered to Collect Exhaled Breath Condensate (EBC) and their Applications

ABSTRACT IMPACT: Human exhaled breath is rich in metabolomic content that represents pulmonary function and gas exchange with blood, which can provide insights into an individual’s state of health. OBJECTIVES/GOALS: Human exhaled breath is rich in metabolomic content that represents pulmonary function and gas exchange with blood. It contains a mixture of compounds that offer insight into an individual’s state of health. Here, we present two novel non-invasive breath sampling devices for use in basic medical practice. METHODS/STUDY POPULATION: The two breath samplers have a disposable mouthpiece, a set of inhale and exhale one-way flap valves to allow condensation of exhaled breath only, and a saliva filter. The housing is constructed out of Teflon®, a chemically inert material to reduce chemical absorbance. The first device condenses exhaled breath into a frozen condensate using dry ice pellets and the other is a miniaturized design that liquifies exhaled breath on a condenser surface with micropatterned features on a cooling plate. Both designs have individual strategic and analytical advantages: frozen exhaled breath condensate (EBC) has high retention of analytes and sample volume; EBC collected in liquid phase offers facilitated sample collection and device portability. RESULTS/ANTICIPATED RESULTS: We investigated if breath aerosol size distribution affects the types or abundances of metabolites. We modified the geometry of the first device to redirect aerosol trajectories based on size. The trapping of larger aerosols increases with filter length, thus altering the aerosol size distribution although no significant changes in the metabolite profiles were found. With the miniaturized device, metabolite abundances were measured in a small cohort of healthy control and mild asthmatic subjects. Differences among subjects were found, as well as main differences between control and asthmatic groups. All analyses of EBC were performed with liquid chromatography - mass spectrometry. Inflammatory suppression found in asthmatic subjects can be explained by prescribed daily use of inhaled corticosteroids. DISCUSSION/SIGNIFICANCE OF FINDINGS: Breath collection devices can be used in intensive care units, outpatient clinics, workplaces, and at home. EBC analysis has been used to monitor asthma and chronic obstructive pulmonary disease. It can be applied to infectious respiratory diseases (e.g. influenza, COVID-19) and for monitoring environmental and occupational chemical exposures.

Associations of Maternal Stress, Prenatal Exposure to Per- and Polyfluoroalkyl Substances (PFAS), and Demographic Risk Factors with Birth Outcomes and Offspring Neurodevelopment: An Overview of the ECHO.CA.IL Prospective Birth Cohorts.

Background. Infants whose mothers experience greater psychosocial stress and environmental chemical exposures during pregnancy may face greater rates of preterm birth, lower birth weight, and impaired neurodevelopment. Methods. ECHO.CA.IL is composed of two cohorts, Chemicals in Our Bodies (CIOB; n = 822 pregnant women and n = 286 infants) and Illinois Kids Development Study (IKIDS; n = 565 mother-infant pairs), which recruit pregnant women from San Francisco, CA and Urbana-Champaign, IL, respectively. We examined associations between demographic characteristics and gestational age, birth weight z-scores, and cognition at 7.5 months across these two cohorts using linear models. We also examined differences in biomarkers of exposure to per- and polyfluoroalkyl substances (PFAS), measured in second-trimester serum, and psychosocial stressors by cohort and participant demographics. Results. To date, these cohorts have recruited over 1300 pregnant women combined. IKIDS has mothers who are majority white (80%), whereas CIOB mothers are racially and ethnically diverse (38% white, 34% Hispanic, 17% Asian/Pacific Islander). Compared to CIOB, median levels of PFOS, a specific PFAS congener, are higher in IKIDS (2.45 ng/mL versus 1.94 ng/mL), while psychosocial stressors are higher among CIOB. Across both cohorts, women who were non-white and single had lower birth weight z-scores relative to white women and married women, respectively. Demographic characteristics are not associated with cognitive outcomes at 7.5 months. Conclusions. This profile of the ECHO.CA.IL cohort found that mothers and their infants who vary in terms of socioeconomic status, race/ethnicity, and geographic location are similar in many of our measures of exposures and cognitive outcomes. Similar to past work, we found that non-white and single women had lower birth weight infants than white and married women. We also found differences in levels of PFOS and psychosocial stressors based on geographic location.

Paternal metabolic and cardiovascular programming of their offspring: A systematic scoping review.

BackgroundThere is lots of evidence that maternal peri-gestational metabolic, genomic and environmental conditions are closely linked to metabolic and cardiovascular outcomes in their offspring later in life. Moreover, there is also lotsof evidence that underlining mechanisms, such as molecular as well as epigenetic changes may alter the intrauterine environment leading to cardio-metabolic diseases in their offspring postnatal. But, there is also increasing evidence that cardio-metabolic diseases may be closely linked to their paternal metabolic risk factors, such as obesity, Type 2 Diabetes and other risk factors.ObjectiveTo analyse the evidence as well as specific risk factors of paternal trans-generational programming of cardio-metabolic diseases in their offspring.MethodsWithin a systematic scoping review, we performed a literature search in MEDLINE (PubMed) and EMBASE databases in August 2020 considering original research articles (2000–2020) that examined the impact of paternal programming on metabolic and cardiovascular offspring health. Epidemiological, clinical and experimental studies as well as human and animal model studies were included.ResultsFrom n = 3.199 citations, n = 66 eligible studies were included. We selected n = 45 epidemiological as well as clinical studies and n = 21 experimental studies. In brief, pre-conceptional paternal risk factors, such as obesity, own birth weight, high-fat and low-protein diet, undernutrition, diabetes mellitus, hyperglycaemia, advanced age, smoking as well as environmental chemical exposure affect clearly metabolic and cardiovascular health of their offspring later in life.ConclusionsThere is emerging evidence that paternal risk factors, such as paternal obesity, diabetes mellitus, nutritional habits, advanced age and exposure to environmental chemicals or cigarette smoke, are clearly associated with adverse effects in metabolic and cardiovascular health in their offspring. Compared to maternal programming, pre-conceptional paternal factors might also have also a substantial effect in the sense of trans-generational programming of their offspring and need further research.

15438 Ability of mathematical models to predict human percutaneous penetration

Background: Human skin is a common route for organic chemicals and drugs to enter the body. To aid with risk management of environmental chemical exposure, the US Environmental Protection Agency estimates percutaneous penetration using mathematical models.

Cohort profile: China National Human Biomonitoring (CNHBM)—A nationally representative, prospective cohort in Chinese population

ObjectiveGlobally, developed countries such as the United States, Canada, Germany, Korea, have carried out long-term and systematic biomonitoring programs for environmental chemicals in their populations. The China National Human Biomonitoring (CNHBM) was to document the extent of human exposure to a wide array of environmental chemicals, to understand exposure profiles, magnitude and ongoing trends in exposure in the general Chinese population, and to establish a national biorepository. MethodsCNHBM adopted three-stage sampling method to obtain a nationally representative sample of the population. A total of 21,888 participants who were permanent residents in 31 provinces were designed to interviewed in this national biomonitoring (152 monitoring sites × 3 survey units × 2 sexes × 6 age groups × 4 persons = 21,888 persons) in 2017–2018. Unlike the US National Health and Nutrition Examination Survey, the CNHBM will follow the same participants in subsequent cycles allowing for dynamic, longitudinal data sets for epidemiologic follow-up. Each survey cycle of CNHBM will last 2 years and each subsequent cycle will occur 3 years after the prior cycle’s completion. ResultsIn 2017–2018, the CNHBM created a large cohort of Chinese citizens that included districts/counties questionnaire, community questionnaire collecting information on villages/communities, individual questionnaire, household questionnaire, comprehensive medical examination, and collection of blood and urine samples for measurement of clinical and exposure biomarkers. A total of 21,746 participants were finally included in CNHBM, accounting for 99.4% of the designed sample size; and 152 PSUs questionnaires, 454 community questionnaires, 21,619 family questionnaires, 21,712 cases of medical examinations, 21,700 individual questionnaires, 21,701 blood samples and 21,704 urine samples were collected, respectively. Planned analyses of blood and urine samples were to measure both inorganic and organic chemicals, including 13 heavy metals and metalloids, 18 poly- and per-fluorinated alkyl substances, 12 phthalate metabolites, 9 polycyclic aromatic hydrocarbons metabolites, 4 environmental alkylated phenols, and 2 benzene metabolites. ConclusionsCNHBM established the first nationally representative, prospective cohort in the Chinese population to understand the baseline and trend of internal exposure of environmental chemicals in general population, and to understand environmental toxicity.