Faculty Bibliography

Although human exposure to microplastics (MPs) and the health effects thereof are a global concern, little is known about the magnitude of exposure. In this study, we quantitatively determined the concentrations of polyethylene terephthalate (PET) and polycarbonate (PC) MPs in three meconium and six infant and 10 adult feces samples collected from New York State. PET and PC MPs were found in some meconium samples (at concentration ranges from below the limit of quantification [<LOQ] to 12,000 and <LOQ-110 ng/g dry weight, respectively) and all infant stool specimens (PET: 5700-82,000 ng/g, median, 36,000 ng/g; PC: 49-2100 ng/g, median, 78 ng/g). They were also found in most (PET) or all (PC) adult stool samples but at concentrations an order of magnitude lower than in infants for PET MPs (<LOQ-16,000 ng/g, median, 2600 ng/g). The estimated mean daily exposures from the diet of infants to PET and PC MPs were 83,000 and 860 ng/kg body weight per day, respectively, which were significantly higher than those of adults (PET: 5800 ng/kg-bw/day; PC: 200 ng/kg-bw/d). Our study suggests that infants are exposed to higher levels of MPs than adults.

Despite the widespread use of primary aromatic amines (AAs) in consumer products, little is known about their prevalence in house dust. In this study, we investigated the occurrence of 35 AAs and two tobacco chemical markers (nicotine and its breakdown product cotinine) in 119 samples of house dust collected from five provinces in China. Ten of the 35 AAs and [nicotine and/or cotinine] were found in >80% and 100% of the samples, respectively, at concentration ranges of 29.1-19,200 (median: 700 ng/g) and 23.2-22,400 (4600) ng/g, respectively. Aniline was the predominant AA found in all dust samples (median: 257 ng/g). Dust samples from Henan and Shanxi provinces contained higher summed concentrations of the 10 AAs than those from Sichuan and Shandong, although the concentrations did not vary significantly among the five provinces (p > 0.05). A significant (p = 0.048), positive correlation (r = 0.882) existed between concentrations of nicotine and cotinine in dust samples. Similarly, concentrations of AAs were significantly correlated with those of nicotine in dust samples. Dyestuffs, rubber products, polyurethane foam and tobacco smoke are the major sources of AAs in the indoor environment. The estimated daily intakes (EDI) through dust ingestion ranged from 0.349 (adults) to 6.62 ng/kg-bw/day (toddlers) for AAs and from 1.27 to 51.1 ng/kg-bw/day for nicotine which are below the current tolerable daily intakes.

BACKGROUND:Prenatal exposures to per- and polyfluoroalkyl substances (PFAS) have been linked to reduced fetal growth. However, the detailed molecular mechanisms remain largely unknown. This study aims to investigate biological pathways and intermediate biomarkers underlying the association between serum PFAS and fetal growth using high-resolution metabolomics in a cohort of pregnant African American women in the Atlanta area, Georgia. METHODS:Serum perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) measurements and untargeted serum metabolomics profiling were conducted in 313 pregnant African American women at 8-14 weeks gestation. Multiple linear regression models were applied to assess the associations of PFAS with birth weight and small-for-gestational age (SGA) birth. A high-resolution metabolomics workflow including metabolome-wide association study, pathway enrichment analysis, and chemical annotation and confirmation with a meet-in-the-middle approach was performed to characterize the biological pathways and intermediate biomarkers of the PFAS-fetal growth relationship. RESULTS:-unit increase in serum PFNA concentration was significantly associated with higher odds of SGA birth (OR = 1.32, 95% CI 1.07, 1.63); similar but borderline significant associations were found in PFOA (OR = 1.20, 95% CI 0.94, 1.49) with SGA. Among 25,516 metabolic features extracted from the serum samples, we successfully annotated and confirmed 10 overlapping metabolites associated with both PFAS and fetal growth endpoints, including glycine, taurine, uric acid, ferulic acid, 2-hexyl-3-phenyl-2-propenal, unsaturated fatty acid C18:1, androgenic hormone conjugate, parent bile acid, and bile acid-glycine conjugate. Also, we identified 21 overlapping metabolic pathways from pathway enrichment analyses. These overlapping metabolites and pathways were closely related to amino acid, lipid and fatty acid, bile acid, and androgenic hormone metabolism perturbations. CONCLUSION/CONCLUSIONS:In this cohort of pregnant African American women, higher serum concentrations of PFOA and PFNA were associated with reduced fetal growth. Perturbations of biological pathways involved in amino acid, lipid and fatty acid, bile acid, and androgenic hormone metabolism were associated with PFAS exposures and reduced fetal growth, and uric acid was shown to be a potential intermediate biomarker. Our results provide opportunities for future studies to develop early detection and intervention for PFAS-induced fetal growth restriction.

BACKGROUND:Prenatal exposure to mixtures of nonpersistent chemicals is universal. Most studies examining these chemicals in association with fetal growth have been restricted to single exposure models, ignoring their potentially cumulative impact. OBJECTIVE:We aimed to assess the association between prenatal exposure to a mixture of phthalates, bisphenols, and organophosphate (OP) pesticides and fetal measures of head circumference, femur length, and weight. METHODS: RESULTS: DISCUSSION/CONCLUSIONS:Higher exposure to a mixture of phthalates, bisphenols, and OP pesticides was associated with lower EFW in the midpregnancy period. In late pregnancy, these differences were similar but less pronounced. At birth, the only associations observed appeared when comparing individuals from Q1 and Q4. This finding suggests that even low levels of exposure may be sufficient to influence growth in early pregnancy, whereas higher levels may be necessary to affect birth weight. Joint exposure to nonpersistent chemicals may adversely impact fetal growth, and because these exposures are widespread, this impact could be substantial. https://doi.org/10.1289/EHP9178.

Onondaga Lake in central New York State was listed as a Superfund site in 1994 due to industrial disposal of pollutants. A biomonitoring program was conducted to assess exposure to over 70 legacy contaminants and contaminants of emerging concern in populations disproportionately at risk for exposure residing near Onondaga Lake and to educate these communities on how to reduce exposures. The populations of focus were refugees from Burma and Bhutan and low-income, primarily African American, anglers (urban anglers). These communities consume locally caught fish for economic as well as cultural reasons and therefore may be at higher risk of exposure. This study focuses on assessment of exposure to per- and polyfluoroalkyl substances (PFAS) and associations with local fish consumption. Using respondent driven sampling, 311 refugees and 89 urban anglers were enrolled in the study. Following informed consent, study participants provided blood and urine specimens and completed a questionnaire. Percentiles of locally caught fish meals in the past 12 months by race/ethnicity groups showed that the Burmese participants of Karen ethnicity were the highest consumers, with a median of 135 meals compared to 103 meals for the other Burmese participants, 70 meals for the urban anglers, and 44 meals for the Bhutanese participants. Compared to the National Health and Nutrition Examination Survey (NHANES) 2015-16 sample of the general U.S. population, the Karen participants had markedly elevated perfluorooctane sulfonic acid (PFOS) and perfluorodecanoic acid (PFDA) levels with median serum concentrations 9.5 times greater (41.6 ng/mL vs. 4.4 ng/mL) and 26.9 times greater (2.69 ng/mL vs. 0.10 ng/mL), respectively; the other Burmese participants had moderately elevated levels of PFOS and PFDA with median serum concentrations 3.0 times greater (13.3 ng/mL vs. 4.4 ng/mL) and 7.3 greater times greater (0.73 ng/mL vs. 0.10 ng/mL), respectively; and, PFAS levels were not elevated in the Bhutanese or urban angler cohorts. Male gender was consistently the strongest predictor of PFAS exposure among all study cohorts. A positive association between local fish consumption was indicated only for PFOS among urban anglers. An association between local fish consumption and PFAS was not statistically significant among the refugee cohorts, perhaps due to the lack of 'lower-end' exposure or exposure variability. Community events were held by the program staff to present the biomonitoring results and distribute community outreach materials with visual aids specific for the study populations to promote safe fish eating.

Single-use or disposable facemasks have been widely used by the public for personal protection against the spread of COVID-19. The majority of disposable facemasks are made of synthetic polymers such as polypropylene, polyethylene terephthalate (as polyester), and polystyrene, and could therefore be a source of human exposure to plasticizers that are incorporated into these polymers during production. Little is known, however, about the occurrence of plasticizers in facemasks. In this study, we determined the concentrations of nine phthalate diesters and six non-phthalate plasticizers in 66 facemasks purchased in the United States. Among phthalate diesters, dibutyl phthalate, di(2-ethylhexyl)phthalate, di-iso-butyl phthalate, and butyl benzyl phthalate were found in all facemask samples, at median concentrations of 486, 397, 254, and 92 ng/g, respectively. Among non-phthalate plasticizers, dibutyl sebacate (median: 3390 ng/g) and di(2-ethylhexyl)adipate (352 ng/g) were found at notable concentrations. Inhalation exposure to select phthalate and non-phthalate plasticizers from the use of facemasks was estimated to range from 0.1 to 3.1 and 3.5 to 151 ng/kg-bw/d, respectively. To our knowledge, this is the first study to report the occurrence of phthalate and non-phthalate plasticizers in facemasks collected from the United States.

Contamination levels and distribution patterns of ten typical phthalic acid esters (PAEs) were investigated in various types of water samples collected from Hanoi metropolitan area in Vietnam. Concentrations of 10 PAEs in bottled water, tap water, lake water, and wastewater samples were measured in the ranges of 1640-15,700 ng/L (mean/median: 6400/5820 ng/L), 2100-18,000 ng/L (mean/median: 11,200/9270 ng/L), 19,600-127,000 ng/L (mean/median: 51,800/49,300 ng/L), and 20,700-405,000 ng/L (mean/median: 121,000/115,000 ng/L), respectively. Among PAEs, di-(2-ethylhexyl) phthalate (DEHP) accounted for a major proportion of total concentrations (45%) in wastewater, followed by diisobutyl phthalate (DiBP, 10.3%), and dibutyl phthalate (DBP, 9.53%). Concentrations of PAEs in wastewater decreased significantly with distance from the wastewater treatment plants (WWTPs). Concentrations of PAEs in surface water samples did not vary greatly between locations. PAEs were found in bottled water in the following order: DBP (22.4%), DiBP (22.3%), benzylbutyl phthalate (BzBP, 20.1%), and DEHP (15.5%). The estimated mean exposure doses of 10 PAEs through consumption of drinking water for adults and children in Vietnam were 254 and 256 ng/kg-bw/day, respectively. Capsule: Highest concentrations of PAEs were measured in wastewater, followed by lake water, tap water, and bottled water.

BACKGROUND:Fetal exposure to bisphenols is associated with altered fetal growth, adverse birth outcomes and childhood cardio-metabolic risk factors. Metabolomics may serve as a tool to identify the mechanisms underlying these associations. We examined the associations of maternal bisphenol urinary concentrations in pregnancy with neonatal metabolite profiles from cord blood. METHODS:In a population-based prospective cohort study among 225 mother-child pairs, maternal urinary bisphenol A, S and F concentrations in first, second and third trimester were measured. LC-MS/MS was used to determine neonatal concentrations of amino acids, non-esterified fatty acids (NEFA), phospholipids (PL), and carnitines in cord blood. RESULTS:No associations of maternal total bisphenol concentrations with neonatal metabolite profiles were present. Higher maternal average BPA concentrations were associated with higher neonatal mono-unsaturated alkyl-lysophosphatidylcholine concentrations, whereas higher maternal average BPS was associated with lower neonatal overall and saturated alkyl-lysophosphatidylcholine (p-values < 0.05).Trimester-specific analyses showed that higher maternal BPA, BPS and BPF were associated with alterations in neonatal NEFA, diacyl-phosphatidylcholines, acyl-alkyl-phosphatidylcholines, alkyl-lysophosphatidylcholine, sphingomyelines and acyl-carnitines, with the strongest effects for third trimester maternal bisphenol and neonatal diacyl-phosphatidylcholine, sphingomyeline and acyl-carnitine metabolites (p-values < 0.05). Associations were not explained by maternal socio-demographic and lifestyle characteristics or birth characteristics. DISCUSSION/CONCLUSIONS:Higher maternal bisphenol A, F and S concentrations in pregnancy are associated with alterations in neonatal metabolite profile, mainly in NEFA, PL and carnitines concentrations. These findings provide novel insight into potential mechanisms underlying associations of maternal bisphenol exposure during pregnancy with adverse offspring outcomes but need to be replicated among larger, diverse populations.

Background/UNASSIGNED: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. Methods/UNASSIGNED: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. Results/UNASSIGNED: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. Conclusion/UNASSIGNED:First study to report urinary trace element levels showed a possible link between thyroid disorders and trace element exposure which reflect the environmental pollution..

BACKGROUND:Phthalates are commonly used endocrine-disrupting chemicals that are ubiquitous in the general population. Prenatal phthalate exposure may alter placental physiology and fetal development, leading to adverse perinatal and childhood health outcomes. OBJECTIVE:We examined associations between prenatal phthalate exposure in the second and third trimesters and the placental transcriptome at birth, including genes and long noncoding RNAs (lncRNAs), to gain insight into potential mechanisms of action during fetal development. METHODS: RESULTS:was associated with multiple phthalate metabolites. Third-trimester MCIOP and mono-isobutyl phthalate concentrations were significantly associated with placental expression of 18 genes and two genes, respectively. Expression of genes within 27 biological pathways was associated with mono-methyl phthalate, MCIOP, and monoethyl phthalate concentrations. DISCUSSION/CONCLUSIONS:by phthalate exposure. https://doi.org/10.1289/EHP8973.