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There is a diversity of chemicals to which humans are potentially exposed. Few of these chemicals have linked human biomonitoring data, and most have very limited neurotoxicity testing. Of particular concern are environmental exposures impacting children, who constitute a population of heightened susceptibility due to rapid neural growth and plasticity, yet lack biomonitoring data compared to other age/population subgroups. This study set out to develop a prioritized list of neuroactive substances, titled the Environmental NeuRoactIve CHemicals (ENRICH) list, to be used as a defined screening library in the evaluation of human biological samples, with emphasis on early childhood-relevant environmental exposures. In silico database mining approaches were used to prioritize chemicals based upon likelihood of neuroactivity, human exposure, and feasible detection in biological samples. Evidence of neuroactivity was compiled across in vitro high-throughput screening, animal testing, and/or human epidemiological findings. Chemicals were considered for their likelihood of human exposure and detection presence in biological samples (including metabolites), with additional evidence indicating presence within child-relevant products. The resulting list of 1827 chemicals were ranked using a Chemical Prioritization Index. Manual inclusion/exclusion criteria were employed for the top-ranking chemical candidates to ensure that chemicals were within the study's scope (i.e., environmentally relevant) and, for the purposes of biomonitoring, had properties amenable to mass spectrometry methods. These elements were combined to produce the ENRICH list of 250 top-ranking chemicals, spanning pesticides and those used in home maintenance, personal care, cleaning products, vehicles, arts and crafts, and consumer electronics, among other sources. Chemicals were additionally evaluated for high-throughput toxicokinetics to predict how much of a chemical and/or its metabolite(s) may reach urine, as an example biological matrix for practical use in biomonitoring efforts. This novel study couples databases and in silico-based predictions to prioritize chemicals in the environment with potential neurological impacts for future study., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: During the 2010 Deepwater Horizon (DWH) disaster, oil spill response and cleanup (OSRC) workers were exposed to toxic volatile components of crude oil. Few studies have examined exposure to individual volatile hydrocarbon chemicals below occupational exposure limits in relation to neurologic function among OSRC workers., Objectives: To investigate the association of several spill-related chemicals (benzene, toluene, ethylbenzene, xylene, n-hexane, i.e., BTEX-H) and total petroleum hydrocarbons (THC) with neurologic function among DWH spill workers enrolled in the Gulf Long-term Follow-up Study., Methods: Cumulative exposure to THC and BTEX-H across the oil spill cleanup period were estimated using a job-exposure matrix that linked air measurement data to detailed self-reported DWH OSRC work histories. We ascertained quantitative neurologic function data via a comprehensive test battery at a clinical examination that occurred 4-6 years after the DWH disaster. We used multivariable linear regression and modified Poisson regression to evaluate relationships of exposures (quartiles (Q)) with 4 neurologic function measures. We examined modification of the associations by age at enrollment (<50 vs. ≥50 years)., Results: We did not find evidence of adverse neurologic effects from crude oil exposures among the overall study population. However, among workers ≥50 years of age, several individual chemical exposures were associated with poorer vibrotactile acuity of the great toe, with statistically significant effects observed in Q3 or Q4 of exposures (range of log mean difference in Q4 across exposures: 0.13-0.26 μm). We also observed suggestive adverse associations among those ≥ age 50 years for tests of postural stability and single-leg stance, although most effect estimates did not reach thresholds of statistical significance (p < 0.05)., Conclusions: Higher exposures to volatile components of crude oil were associated with modest deficits in neurologic function among OSRC workers who were age 50 years or older at study enrollment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: During the 2010 Deepwater Horizon (DWH) disaster, in-situ burning and flaring were conducted to remove oil from the water. Workers near combustion sites were potentially exposed to burning-related fine particulate matter (PM 2.5 ). Exposure to PM 2.5 has been linked to increased risk of coronary heart disease (CHD), but no study has examined the relationship among oil spill workers., Objectives: To investigate the association between estimated PM 2.5 from burning/flaring of oil/gas and CHD risk among the DWH oil spill workers., Methods: We included workers who participated in response and cleanup activities on the water during the DWH disaster (N = 9091). PM 2.5 exposures were estimated using a job-exposure matrix that linked modelled PM 2.5 concentrations to detailed DWH spill work histories provided by participants. We ascertained CHD events as the first self-reported physician-diagnosed CHD or a fatal CHD event that occurred after each worker's last day of burning exposure. We estimated hazard ratios (HR) and 95% confidence intervals (95%CI) for the associations between categories of average or cumulative daily maximum PM 2.5 exposure (versus a referent category of water workers not near controlled burning) and subsequent CHD. We assessed exposure-response trends by examining continuous exposure parameters in models., Results: We observed increased CHD hazard among workers with higher levels of average daily maximum exposure (low vs. referent: HR = 1.26, 95% CI: 0.93, 1.70; high vs. referent: HR = 2.11, 95% CI: 1.08, 4.12; per 10 μg/m 3 increase: HR = 1.10, 95% CI: 1.02, 1.19). We also observed suggestively elevated HRs among workers with higher cumulative daily maximum exposure (low vs. referent: HR = 1.19, 95% CI: 0.68, 2.08; medium vs. referent: HR = 1.38, 95% CI: 0.88, 2.16; high vs. referent: HR = 1.44, 95% CI: 0.96, 2.14; per 100 μg/m 3 -d increase: HR = 1.03, 95% CI: 1.00, 1.05)., Conclusions: Among oil spill workers, exposure to PM 2.5 from flaring/burning of oil/gas was associated with increased risk of CHD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Although evidence suggests relationships between some crude oil components and glycemic dysregulation, no studies have examined oil spill-related chemical exposures in relation to type 2 diabetes mellitus (DM) risk. This study examined the relationship between total hydrocarbon (THC) exposure among workers involved in the 2010 Deepwater Horizon (DWH) oil spill and risk of DM up to 6 years afterward., Methods: Participants comprised 2660 oil-spill cleanup or response workers in the prospective GuLF Study who completed a clinical exam and had no self-reported DM diagnosis prior to the spill. Maximum THC exposure was estimated with a job-exposure matrix based on interview data and personal measurements taken during cleanup operations. We defined incident DM by self-reported physician diagnosis of DM, antidiabetic medication use, or a measured hemoglobin A1c value ≥ 6.5%. We used log binomial regression to estimate risk ratios (RRs) for DM across ordinal categories of THC exposure. The fully adjusted model controlled for age, sex, race/ethnicity, education, employment status, and health insurance status. We also stratified on clinical body mass index categories., Results: We observed an exposure-response relationship between maximum daily ordinal THC exposure level and incident DM, especially among overweight participants. RRs among overweight participants were 0.99 (95% CI: 0.37, 2.69), 1.46 (95% CI: 0.54, 3.92), and 2.11 (95% CI: 0.78, 5.74) for exposure categories 0.30-0.99 ppm, 1.00-2.99 ppm, and ≥3.00 ppm, respectively (p trend  = 0.03)., Conclusion: We observed suggestively increasing DM risk with increasing THC exposure level among overweight participants, but not among normal weight or obese participants., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Over ten years after the Deepwater Horizon (DWH) oil spill, our understanding of long term respiratory health risks associated with oil spill response exposures is limited. We conducted a prospective analysis in a cohort of U.S. Coast Guard personnel with universal military healthcare., Methods: For all active duty cohort members (N = 45,193) in the DWH Oil Spill Coast Guard Cohort Study we obtained medical encounter data from October 01, 2007 to September 30, 2015 (i.e., ~2.5 years pre-spill; ~5.5 years post-spill). We used Cox Proportional Hazards regressions to calculate adjusted hazard ratios (aHR), comparing risks for incident respiratory conditions/symptoms (2010-2015) for: responders vs. non-responders; responders reporting crude oil exposure, any inhalation of crude oil vapors, and being in the vicinity of burning crude oil versus responders without those exposures. We also evaluated self-reported crude oil and oil dispersant exposures, combined. Within-responder comparisons were adjusted for age, sex, and smoking., Results: While elevated aHRs for responder/non-responder comparisons were generally weak, within-responder comparisons showed stronger risks with exposure to crude oil. Notably, for responders reporting exposure to crude oil via inhalation, there were elevated risks for allsinusitis (aHR = 1.48; 95%CI, 1.06-2.06), unspecified chronic sinusitis (aHR = 1.55; 95%CI, 1.08-2.22), chronic obstructive pulmonary disease (COPD) and other allied conditions (aHR = 1.43; 95%CI, 1.00-2.06), and dyspnea and respiratory abnormalities (aHR = 1.29; 95%CI, 1.00-1.67); there was a suggestion of elevated risk for diseases classified as asthma and reactive airway diseases (aHR = 1.18; 95%CI, 0.98-1.41), including the specific condition, asthma (aHR = 1.35; 95%CI, 0.80-2.27), the symptom, shortness of breath (aHR = 1.50; 95%CI, 0.89-2.54), and the overall classification of chronic respiratory conditions (aHR = 1.18; 95%CI, 0.98-1.43). Exposure to both crude oil and dispersant was positively associated with elevated risk for shortness of breath (HR = 2.24; 95%CI, 1.09-4.64)., Conclusions: Among active duty Coast Guard personnel, oil spill clean-up exposures were associated with moderately increased risk for longer term respiratory conditions., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Both essential and non-essential metals come from natural and anthropogenic sources. Metals can bioaccumulate in humans and may impact human health, including hypertension., Methods: Blood metal (cadmium, lead, mercury, manganese, and selenium) concentrations were measured at baseline for a sample of participants in the Gulf Long-Term Follow-up (GuLF) Study. The GuLF Study is a prospective cohort study focused on potential health effects following the 2010 Deepwater Horizon oil spill. Hypertension was defined as high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure or taking anti-hypertensive medications. A total of 957 participants who had blood measurement for at least one metal, baseline blood pressure measurements, information on any anti-hypertensive medication use, and relevant covariates were included in this cross-sectional analysis. We used Poisson regression to explore the association between individual blood metal levels and hypertension. Quantile-based g-computation was used to investigate the association between the metal mixture and hypertension. We also explored the association between individual blood metal levels and continuous blood pressure measurements using general linear regression., Results: Comparing the highest quartile of blood metals with the lowest (Q4vs1), the hypertension prevalence ratio (PR) was 0.92 (95 % confidence interval (CI) = 0.73,1.15) for cadmium, 0.86 (95%CI = 0.66,1.12) for lead, 0.89 (95%CI = 0.71,1.12) for mercury, 1.00 (95%CI = 0.80,1.26) for selenium, and 1.22 (95%CI = 0.95,1.57) for manganese. We observed some qualitative differences across race and BMI strata although none of these differences were statistically significant. In stratified analyses, the PR (Q4vs1) for mercury was 0.69 (95%CI = 0.53, 0.91) in White participants and 1.29 (95%CI = 0.86,1.92) in Black participants (p for interaction = 0.5). The PR (Q4vs1) for manganese was relatively higher in Black participants (PR = 1.37, 95%CI = 0.92,2.05) than in White participants (PR = 1.15, 95%CI = 0.83,1.60, p for interaction = 0.5), with a suggestive dose-response among Blacks. After stratifying by obesity (BMI ≥30 and < 30), positive associations of of hypertension with cadmium (PR [Q4vs1] = 1.19, 95%CI = 0.91,1.56, p for interaction = 0.5), lead (PR [Q4vs1] = 1.14, 95%CI = 0.84,1.55, p for interaction = 1.0) and manganese (PR = 1.25, 95%CI = 0.93,1.68, p for interaction = 0.8) were observed in participants with BMI≥30, but not in participants with BMI<30. The joint effect of the metal mixture was 0.96 (95%CI = 0.73,1.27). We did not observe clear associations between blood metal levels and continuous blood pressure measurements., Conclusion: We did not find overall cross-sectional associations between blood cadmium, lead, mercury, selenium levels and hypertension or blood pressure. We found some evidence suggesting that manganese might be positively associated with risk of hypertension. Associations varied somewhat by race and BMI., (Published by Elsevier Inc.)

Background: Polychlorinated biphenyls (PCBs) were used in electrical equipment and a range of construction materials. Although banned in the United States and most of Europe in the 1970s, they are highly persistent in the environment and bioaccumulate. Whether PCBs are associated with liver cancer risk at general population levels is unknown., Methods: This study consisted of 136 incident liver cancer cases and 408 matched controls from the Kaiser Permanente Northern California Multiphasic Health Checkup (MHC) cohort and 84 cases and 252 matched controls from the Norwegian Janus cohort. Sera collected in the 1960s-1980s were measured for 37 PCB congeners and markers of hepatitis B (HBV) and C (HCV) infection. Odds ratios (OR) and 95% confidence intervals (CI) for tertiles of each lipid-adjusted PCB were estimated from conditional logistic regression. We also examined the molar sum of congeners in groups: total PCBs; low, medium, and high chlorination; and Wolff functional groups., Results: Concentrations of individual congeners from the 1960s/1970s sera ranged from 1.3-123.0 and 1.4-116.0 ng/g lipid among MHC cases and controls, respectively, and from 1.9-258.0 and 1.9-271.0 ng/g lipid among Janus cases and controls, respectively. Among MHC participants with sera from the 1960s, collected an average of 27 years before diagnosis among cases, the top tertile of PCBs 151, 170, 172, 177, 178, 180, and 195 was significantly associated with elevated odds of liver cancer (OR range = 2.01-2.38); most of these congeners demonstrated exposure-response trends. For example, OR tertile 3vs1  = 2.38 (95% CI: 1.22-4.64, p-trend = 0.01) for PCB 180. As a group, Wolff group 1b congeners, which are biologically persistent and weak phenobarbital inducers, were associated with increased odds. In MHC participants, ever vs. never HBV or HCV infection modified the PCB-liver cancer associations. There was little evidence of an association between PCBs and odds of liver cancer among the Janus cohort., Discussion: We observed associations between a number of PCB congeners and increased odds of liver cancer among MHC, but not Janus, participants with sera from the 1960s/1970s., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Much of the marked increase in incidence of non-Hodgkin lymphoma (NHL) over the past few decades remains unexplained. Organochlorines, including organochlorine pesticides (OCPs), have been implicated as possible contributors to the increase, but the evidence is inconsistent., Objectives: To investigate the relation between pre-diagnostic levels of OCPs and risk of NHL in a case-control study nested within the population-based Janus Serum Bank Cohort in Norway., Methods: Prediagnostic concentrations of 11 OCPs or OCP metabolites were measured in baseline blood samples collected between 1972 and 1978 from 190 cases and 190 controls matched on sex, county, age at blood draw, and date of blood draw. We conducted conditional logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for each quartile of lipid-corrected OCP/metabolite relative to the lowest quartile., Results: We observed non-significantly elevated ORs across quartiles of β-hexachlorocyclohexane compared to the lowest quartile (OR range: 1.40-1.82) although with no apparent monotonic exposure-response relationship. We also found an inverse association between risk of NHL and o,p'-DDT (OR for Q 4 vs. Q 1  = 0.44, 95% CI: 0.19, 1.01; p-trend = 0.05). In analyses stratified by age at blood collection and duration of follow-up, several other analytes, primarily chlordane-related compounds, showed inverse associations among younger participants or those with longer follow-up time between blood draw and NHL diagnosis., Conclusions: We found only limited evidence of positive association between selected OCPs and development of NHL., Competing Interests: Declaration of competing interest The authors declare they have no actual or potential competing financial interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: The 2010 Deepwater Horizon (DWH) disaster exposed tens of thousands of oil spill response and cleanup (OSRC) workers to hydrocarbons and other hazardous chemicals. Some hydrocarbons, such as toluene and hexane, have been found to have acute adverse effects on the central nervous system in occupational settings. However, no studies have examined the association between oil spill exposures and neurobehavioral function., Methods: We used data from the Gulf Long-term Follow-up Study, a cohort of adults who worked on the DWH response and cleanup. Total hydrocarbon (THC) exposure attributed to oil spill cleanup work was estimated from a job-exposure matrix linking air measurement data to detailed cleanup work histories. Participants were also categorized into 6 job categories, or OSRC classes, based on their activity with the highest exposure. Neurobehavioral performance was assessed at a clinical exam 4-6 years after the spill. We used multivariable linear regression to evaluate relationships of ordinal THC levels and OSRC classes with 16 neurobehavioral outcomes., Results: We found limited evidence of associations between THC levels or OSRC classes and decreased neurobehavioral function, including attention, memory, and executive function. Workers exposed to ≥3 ppm THC scored significantly worse (difference 1.0-2.9ppm  = -0.39, 95% confidence interval (CI) = -0.74, -0.04) than workers exposed to <0.30 ppm THC for the digit span forward count test. There was also a possible threshold effect above 1 ppm THC for symbol digit test total errors (difference 1.0-2.9ppm  = -0.56 (95% CI = -1.13, -0.003), difference ≥3.0ppm  = -0.55 (95% CI = -1.20, 0.10)). Associations appeared to be stronger in men than in women. A summary latency measure suggested an association between more highly exposed jobs (especially support of operations workers) and decreased neurobehavioral function., Conclusion: OSRC-related exposures were associated with modest decreases in neurobehavioral function, especially attention, memory, and executive function., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The chemicals benzene, toluene, ethylbenzene, and xylenes (BTEX) are neuroactive. Exposures often co-occur because they share common sources. We examined neurologic effects of environmental BTEX exposure among U.S. Gulf coast residents taking into account concomitant exposures., Methods: We measured blood concentrations of BTEX in 690 Gulf state residents. Neurologic symptoms were ascertained via telephone interview. We used log-binomial regression to estimate associations between blood BTEX levels and self-reported neurologic symptoms independently for the presence of any neurologic, central (CNS), or peripheral nervous system (PNS) symptoms. We estimated associations in single chemical models mutually adjusted for co-occurring BTEX and used weighted quantile sum regression to model associations between the combined BTEX mixture and neurologic symptoms., Results: Half (49%) of participants reported at least one neurologic symptom. Each BTEX chemical was associated with increased CNS and PNS symptoms in single-chemical models comparing the highest to lowest quartile of exposure. After adjusting for coexposures, benzene was associated with CNS symptoms among all participants (PR = 2.13, 95% CI: 1.27, 3.57) and among nonsmokers (PR = 2.30, 95% CI: 1.35, 3.91). After adjusting for coexposures, associations with toluene were apparent only for reporting multiple PNS symptoms (PR = 2.00, 95% CI: 0.96, 4.16). In mixture analyses, a one-quartile increase in BTEX exposure was associated with neurologic symptoms (OR = 1.47, 95% CI: 1.11, 1.98). The weighted quantile sum index weighted benzene most heavily, which was consistent with single chemical analyses., Conclusions: Increasing blood benzene concentration was associated with increased prevalence of CNS symptoms. In this sample, BTEX-associated neurologic effects are likely driven by exposure to benzene and, to a lesser extent, toluene., (Copyright © 2019. Published by Elsevier Inc.)

Background: Chemical, physical and psychological stressors due to the 2010 Deepwater Horizon oil spill may impact coronary heart disease (CHD) among exposed populations. Using longitudinal information from two interviews in the Gulf Long Term Follow-up (GuLF) STUDY, we assessed CHD among oil spill workers and community members., Objective: To assess the associations between duration of oil spill clean-up work, residential proximity to the oil spill, and incidence of self-reported myocardial infarction or fatal CHD., Methods: Among respondents with two GuLF STUDY interviews (n = 21,256), there were 395 first incident heart disease events (self-reported myocardial infarction or fatal CHD) across 5 years. We estimated hazard ratios (HR) and 95% confidence intervals (95%CI) for associations with duration of oil spill clean-up work and residential proximity to the oil spill. To assess potential impacts of non-response, we compared covariate distributions for those who did (n = 21,256) and did not (n = 10,353) complete the second interview and used inverse probability (IP) of censoring weights to correct for potential non-response bias., Results: Living in proximity to the oil spill (vs. living further away) was associated with heart disease, with [HR(95%CI) = 1.30(1.01-1.67)] and without [1.29(1.00-1.65)] censoring weights. For work duration, hazard of heart disease appeared to be higher for those who worked > 180 days (vs. 1-30 days), with and without censoring weights [1.43(0.91-2.25) and 1.36(0.88-2.11), respectively]. Associations persisted throughout the 5-year follow-up., Conclusions: Residential proximity to the spill and duration of clean-up work were associated with a suggested 29-43% higher hazard of heart disease events. Associations were robust to censoring., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Polychlorinated biphenyls (PCBs) and organochlorine pesticides have been associated with altered thyroid hormone levels in humans, but their relationship with thyroid cancer is unknown., Methods: We conducted a nested case-control study of thyroid cancer in the Norwegian Janus Serum Bank cohort using pre-diagnostic blood samples from 1972 to 1985. Incident thyroid cancer (n = 108) was ascertained through 2008. Controls were matched 2:1 by age, date of blood draw, gender, and county. We used gas chromatography/mass spectrometry to quantify 36 PCB congeners and metabolites of pesticides DDT, chlordane, hexachlorocyclohexane, and hexachlorobenzene. PCBs and pesticide metabolites were evaluated individually and summed by degree of chlorination and parent compound, respectively. Odds ratios (OR) and 95% confidence intervals (CI) were computed using conditional logistic regression per specified increase in lipid-adjusted concentration. We additionally stratified analyses by birth cohort (1923-1932, 1933-1942, 1943-1957)., Results: Increasing concentration of DDT metabolites (OR per 1000 ng/g = 0.80, 95%CI = 0.66-0.98) was inversely associated with thyroid cancer. Associations for PCBs were null or in inverse direction. We observed interactions for total PCBs, moderately-chlorinated PCBs, and chlordane metabolites with birth cohort (p ≤ 0.04). Among participants born 1943-1957, total PCBs (OR per 100 ng/g = 1.25, 95%CI = 1.00-1.56), moderately-chlorinated PCBs (OR per 100 ng/g = 1.31, 95%CI = 1.01-1.70), and chlordane metabolites (OR per 10 ng/g = 1.78, 95%CI = 1.09-2.93) were positively associated with thyroid cancer. For individuals born before 1943, associations were generally null or in the inverse direction., Conclusions: Emissions of PCBs and OC pesticides varied over time. Different risk patterns by birth cohort suggest the potential importance of timing of exposure in thyroid cancer risk. Further evaluation of these associations is warranted., (Published by Elsevier Inc.)

Introduction: Over 8500 United States Coast Guard (USCG) personnel were deployed in response to the Deepwater Horizon (DWH) oil spill; however, human respiratory effects as a result of spill-related exposures are relatively unknown., Methods: USCG personnel who responded to the DWH oil spill were queried via survey on exposures to crude oil and oil dispersant, and acute respiratory symptoms experienced during deployment. Adjusted log binomial regressions were used to calculate prevalence ratios (PRs) and 95% confidence intervals (CI), investigating the associations between oil spill exposures and respiratory symptoms., Results: 4855 USCG personnel completed the survey. More than half (54.6%) and almost one-fourth (22.0%) of responders were exposed to crude oil and oil dispersants, respectively. Coughing was the most prevalent symptom (19.4%), followed by shortness of breath (5.5%), and wheezing (3.6%). Adjusted analyses showed an exposure-response relationship between increasing deployment duration and likelihood of coughing, shortness of breath, and wheezing in the pre-capping period. A similar pattern was observed in the post-capping period for coughing and wheezing. Adjusted analyses revealed increased PRs for coughing (PR=1.92), shortness of breath (PR=2.60), and wheezing (PR=2.68) for any oil exposure. Increasing frequency of inhalation of oil was associated with increased likelihood of all three respiratory symptoms. A similar pattern was observed for contact with oil dispersants for coughing and shortness of breath. The combination of both oil and oil dispersants presented associations that were much greater in magnitude than oil alone for coughing (PR=2.72), shortness of breath (PR=4.65), and wheezing (PR=5.06)., Conclusions: Results from the present study suggested strong relationships between oil and oil dispersant exposures and acute respiratory symptoms among disaster responders. Future prospective studies will be needed to confirm these findings., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Prenatal exposure to organophosphorus pesticides (OPs) has been associated with different neurodevelopmental outcomes across different cohorts. A phenotypic approach may address some of these differences by incorporating information across scales and accounting for the complex correlational structure of neurodevelopmental outcomes. Additionally, Bayesian hierarchical modeling can account for confounding by collinear co-exposures. We use this framework to examine associations between prenatal exposure to OPs and behavior, executive functioning, and IQ assessed at age 6-9 years in a cohort of 404 mother/infant pairs recruited during pregnancy. We derived phenotypes of neurodevelopment with a factor analysis, and estimated associations between OP metabolites and these phenotypes in Bayesian hierarchical models for exposure mixtures. We report seven factors: 1) Impulsivity and Externalizing, 2) Executive Functioning, 3) Internalizing, 4) Perceptual Reasoning, 5) Adaptability, 6) Processing Speed, and 7) Verbal Intelligence. These, along with the Working Memory Index, were standardized and scaled so that positive values reflected positive attributes and negative values represented adverse outcomes. Standardized dimethylphosphate metabolites were negatively associated with Internalizing factor scores (β^ - 0.13, 95% CI - 0.26, 0.00) but positively associated with Executive Functioning factor scores (β^ 0.18, 95% CI 0.04, 0.31). Standardized diethylphosphate metabolites were negatively associated with the Working Memory Index (β^ - 0.17, 95% CI - 0.33, - 0.03). Associations with factor scores were generally stronger and more precise than associations with individual instrument-specific items. Factor analysis of outcomes may provide some advantages in etiological studies of childhood neurodevelopment by incorporating information across scales to reduce dimensionality and improve precision., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Studies of workers exposed to benzene at average air concentrations below one part per million suggest that benzene, a known hematotoxin, causes hematopoietic damage even at low exposure levels. However, evidence of such effects outside of occupational settings and for other volatile organic compounds (VOCs) is limited., Objective: To investigate associations between ambient exposures to five VOCs, including benzene, and hematologic parameters among adult residents of the U.S. Gulf Coast., Materials and Methods: Blood concentrations of selected VOCs were measured in a sample of adult participants in the Gulf Long-term Follow-up Study (GuLF STUDY) during 2012 and 2013. Complete blood counts with differentials were also performed on a subset of participants (n=406). We used these data together with detailed questionnaire data to estimate adjusted associations between blood BTEXS (benzene, toluene, ethylbenzene, o-xylene, m/p-xylene, and styrene) concentrations and hematologic parameters using generalized linear models., Results: We observed inverse associations between blood benzene concentrations and hemoglobin concentration and mean corpuscular hemoglobin concentration, and a positive association with red cell distribution width among tobacco smoke-unexposed participants (n=146). Among tobacco smoke-exposed participants (n=247), we observed positive associations between blood VOC concentrations and several hematologic parameters, including increased white blood cell and platelet counts, suggestive of hematopoietic stimulation typically associated with tobacco smoke exposure. Most associations were stronger for benzene than for the other VOCs., Conclusions: Our results suggest that ambient exposure to BTEXS, particularly benzene, may be associated with hematologic effects, including decreased hemoglobin concentration, mean corpuscular hemoglobin concentration, and increased red cell distribution width., (Published by Elsevier Inc.)

Background: Tobacco smoke, diet and indoor/outdoor air pollution, all major sources of polycyclic aromatic hydrocarbons (PAHs), have been associated with breast cancer. Aberrant methylation may be an early event in carcinogenesis, but whether PAHs influence the epigenome is unclear, particularly in breast tissue where methylation may be most relevant. We aimed to evaluate the role of methylation in the association between PAHs and breast cancer., Methods: In a population-based case-control study, we measured promoter methylation of 13 breast cancer-related genes in breast tumor tissue (n=765-851 cases) and global methylation in peripheral blood (1055 cases/1101 controls). PAH sources (current active smoking, residential environmental tobacco smoke (ETS), vehicular traffic, synthetic log burning, and grilled/smoked meat intake) were evaluated separately. Logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs)., Results: When comparing methylated versus unmethylated genes, synthetic log use was associated with increased ORs for CDH1 (OR=2.26, 95%CI=1.06-4.79), HIN1 (OR=2.14, 95%CI=1.34-3.42) and RARβ (OR=1.80, 95%CI=1.16-2.78) and decreased ORs for BRCA1 (OR=0.44, 95%CI=0.30-0.66). Residential ETS was associated with decreased ORs for ESR1 (OR=0.74, 95%CI=0.56-0.99) and CCND2 methylation (OR=0.65, 95%CI=0.44-0.96). Current smoking and vehicular traffic were associated with decreased ORs for DAPK (OR=0.53, 95%CI=0.28-0.99) and increased ORs for TWIST1 methylation (OR=2.79, 95%CI=1.24-6.30), respectively. In controls, synthetic log use was inversely associated with LINE-1 (OR=0.59, 95%CI=0.41-0.86)., Discussion: PAH sources were associated with hypo- and hypermethylation at multiple promoter regions in breast tumors and LINE-1 hypomethylation in blood of controls. Methylation may be a potential biologic mechanism for the associations between PAHs and breast cancer incidence., (Published by Elsevier Inc.)

Background: Pesticide exposure has been found to cause renal damage and dysfunction in experimental studies, but epidemiological research on the renal effects of chronic low-level pesticide exposure is limited. We investigated the relationships between end-stage renal disease (ESRD) among wives of licensed pesticide applicators (N=31,142) in the Agricultural Health Study (AHS) and (1) personal pesticide use, (2) exposure to the husband's pesticide use, and (3) other pesticide-associated farming and household activities., Methods: AHS participants reported pesticide exposure via self-administered questionnaires at enrollment (1993-1997). ESRD cases were identified via linkage to the United States Renal Data System. Associations between ESRD and pesticide exposures were estimated with Cox proportional hazard regression models controlling for age at enrollment. Models of associations with farming and household factors were additionally adjusted for personal use of pesticides., Results: We identified 98 ESRD cases diagnosed between enrollment and 31 December 2011. Although women who ever applied pesticides (56% of cohort) were less likely than those who did not apply to develop ESRD (Hazard Ratio (HR): 0.42; 95% CI: 0.28, 0.64), among women who did apply pesticides, the rate of ESRD was significantly elevated among those who reported the highest (vs. lowest) cumulative general pesticide use (HR: 4.22; 95% CI: 1.26, 14.20). Among wives who never applied pesticides, ESRD was associated with husbands' ever use of paraquat (HR=1.99; 95% CI: 1.14, 3.47) and butylate (HR=1.71; 95% CI: 1.00, 2.95), with a positive exposure-response pattern for husband's cumulative use of these pesticides., Conclusions: ESRD may be associated with direct and/or indirect exposure to pesticides among farm women. Future studies should evaluate indirect exposure risk among other rural populations., (Published by Elsevier Inc.)