Pharmacology, Toxicology and Environmental Health Commons^™

An Approach To Identify Gene-Environment Interactions And Reveal New Biological Insight In Complex Traits, Xiaofeng Zhu, Yihe Yang, Noah Lorincz-Comi, Gen Li, Amy R Bentley, Paul S De Vries, Michael Brown, Alanna C Morrison, Charles N Rotimi, W James Gauderman, Dabeeru C Rao, Hugues Aschard

Journal Articles

There is a long-standing debate about the magnitude of the contribution of gene-environment interactions to phenotypic variations of complex traits owing to the low statistical power and few reported interactions to date. to address this issue, the Gene-Lifestyle Interactions Working Group within the Cohorts for Heart and Aging Research in Genetic Epidemiology Consortium has been spearheading efforts to investigate G × E in large and diverse samples through meta-analysis. Here, we present a powerful new approach to screen for interactions across the genome, an approach that shares substantial similarity to the Mendelian randomization framework. We identify and confirm 5 loci …

Joint Problem-Solving Orientation, Mutual Value Recognition, And Performance In Fluid Teamwork Environments, Michaela Kerrissey, Zhanna Novikov

Journal Articles

INTRODUCTION: Joint problem-solving orientation (JPS) has been identified as a factor that promotes performance in fluid teamwork, but research on this factor remains nascent. This study pushes the frontier of understanding about JPS in fluid teamwork environments by applying the concept to within-organization work and exploring its relationships with performance, mutual value recognition (MVR), and expertise variety (EV).

METHODS: This is a longitudinal, survey-based field study within a large United States healthcare organization

RESULTS: Our results affirm a moderated mediation model wherein JPS enhances performance, both directly and through MVR; EV serves as a moderator in the JPS-MVR relationship. JPS …

Developing A National-Scale Exposure Index For Combined Environmental Hazards And Social Stressors And Applications To The Environmental Influences On Child Health Outcomes (Echo) Cohort., Sheena E. Martenies, Mingyu Zhang, Anne E. Corrigan, Anton Kvit, Timothy Shields, William Wheaton, Deana Around Him, Judy Aschner, Maria M. Talavera-Barber, Emily S. Barrett, Theresa M. Bastain, Casper Bendixsen, Carrie V. Breton, Nicole R. Bush, Ferdinand Cacho, Carlos A. Camargo, Kecia N. Carroll, Brian S. Carter, Andrea E. Cassidy-Bushrow, Whitney Cowell, Lisa A. Croen, Dana Dabelea, Cristiane S. Duarte, Anne L. Dunlop, Todd M. Everson, Rima Habre, Tina V. Hartert, Jennifer B. Helderman, Alison E. Hipwell, Margaret R. Karagas, Barry M. Lester, Kaja Z. Lewinn, Sheryl Magzamen, Rachel Morello-Frosch, Thomas G. O'Connor, Amy M. Padula, Michael Petriello, Sheela Sathyanarayana, Joseph B. Stanford, Tracey J. Woodruff, Rosalind J. Wright, Amii M. Kress, Program Collaborators For Environmental Influences On Child Health Outcomes

Manuscripts, Articles, Book Chapters and Other Papers

Tools for assessing multiple exposures across several domains (e.g., physical, chemical, and social) are of growing importance in social and environmental epidemiology because of their value in uncovering disparities and their impact on health outcomes. Here we describe work done within the Environmental influences on Child Health Outcomes (ECHO)-wide Cohort Study to build a combined exposure index. Our index considered both environmental hazards and social stressors simultaneously with national coverage for a 10-year period. Our goal was to build this index and demonstrate its utility for assessing differences in exposure for pregnancies enrolled in the ECHO-wide Cohort Study. Our unitless …

Climate Change Imperils Pediatric Health: Child Advocacy Through Fossil Fuel Divestment., Sandra H. Jee, Elizabeth Friedman, Ruth A. Etzel, Vi T. Nguyen, Todd L. Sack, Kathi J. Kemper

Manuscripts, Articles, Book Chapters and Other Papers

Climate change poses an existential threat to children's health. Divestment of ownership stakes in fossil fuel companies is one tool available to pediatricians to address climate change. Pediatricians are trusted messengers regarding children's health and therefore bear a unique responsibility to advocate for climate and health policies that affect children. Among the impacts of climate change on pediatric patients are allergic rhinitis and asthma; heat-related illnesses; premature birth; injuries from severe storms and fires; vector-borne diseases; and mental illnesses. Children are disproportionately affected as well by climate-related displacement of populations, drought, water shortages, and famine. The human-generated burning of fossil …

Exposure To Pcb126 During The Nursing Period Reversibly Impacts Early-Life Glucose Tolerance, Brittany B. Rice, Keegan W. Sammons, Sara Y. Ngo Tenlep, Madeline T. Weltzer, Leryn J. Reynolds, Cetewayo S. Rashid, Hollie I. Swanson, Kevin J. Pearson

Human Movement Sciences & Special Education Faculty Publications

Polychlorinated biphenyls (PCBs) are persistent environmental organic pollutants known to have detrimental health effects. Using a mouse model, we previously demonstrated that PCB126 exposure before and during pregnancy and throughout the perinatal period adversely affected offspring glucose tolerance and/or body composition profiles. The purpose of this study was to investigate the glucose tolerance and body composition of offspring born to dams exposed to PCB126 during the nursing period only. Female ICR mice were bred, and half of the dams were exposed to either vehicle (safflower oil) or 1 µmole PCB126 per kg of body weight via oral gavage on postnatal …

Review Of Evidence For Environmental Causes Of Uveal Coloboma, Evan B Selzer, Delphine Blain, Robert B Hufnagel, Philip J Lupo, Laura E Mitchell, Brian P Brooks

Journal Articles

Uveal coloboma is a condition defined by missing ocular tissues and is a significant cause of childhood blindness. It occurs from a failure of the optic fissure to close during embryonic development and may lead to missing parts of the iris, ciliary body, retina, choroid, and optic nerve. Because there is no treatment for coloboma, efforts have focused on prevention. While several genetic causes of coloboma have been identified, little definitive research exists regarding the environmental causes of this condition. We review the current literature on environmental factors associated with coloboma in an effort to guide future research and preventative …

Sedation And Acute Encephalopathy In A Pediatric Patient Following Ingestion Of Delta-8-Tetrahydrocannabinol Gummies, Peter Akpunonu, Regan A. Baum, Andrew Reckers, Blake Davidson, Ross Ellison, Matthew Riley, Jordan Trecki, Roy Gerona

Emergency Medicine Faculty Publications

BACKGROUND Delta-8 tetrahydrocannabinol (delta-8 THC) is an isomer of delta-9-tetrahydrocannabinol (delta-9 THC), the primary psychoactive cannabinoid in the marijuana plant. Typically found at lower concentrations in marijuana, delta-8 THC exhibits psychoactive properties similar to delta-9 THC. Products containing delta-8 THC are readily available across the US and currently there is a lack of available confirmatory testing specific to delta-8 THC as there is cross-reactivity to other naturally occurring cannabinoids in standard immunoassays. Pediatric exposures to this substance are on the rise.

CASE REPORT We present a case with laboratory confirmation of a previously healthy 2-year-old girl ingesting approximately 15 mg/kg …

Associations Between Physiological Biomarkers And Psychosocial Measures Of Pregnancy-Specific Anxiety And Depression With Support Intervention, Karen L Weis, Tony T Yuan, Katherine C Walker, Thomas F Gibbons, Wenyaw Chan

Journal Articles

Stress and anxiety significantly impact the hypothalamic-pituitary axis, and in pregnancy, the subsequent maternal-fetal response can lead to poor outcomes. The objective of this study was to assess the association between psychosocial measures of pregnancy-specific anxiety and physiologic inflammatory responses. Specifically, to determine the effectiveness of the Mentors Offering Maternal Support (M-O-M-S

Aluminum Reproductive Toxicity: A Summary And Interpretation Of Scientific Reports, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Publications addressing aluminum (Al)-induced reproductive toxicity were reviewed. Key details were compiled in summary tables. Approximate systemic Al exposure, a measure of bioavailability, was calculated for each exposure, based on the Al percentage in the dosed Al species, Al bioavailability, and absorption time course reports for the exposure route. This was limited to laboratory animal studies because no controlled-exposure human studies were found. Intended Al exposure was compared to unintended dietary Al exposure. The considerable and variable Al content of laboratory animal diets creates uncertainty about reproductive function in the absence of Al. Aluminum-induced reproductive toxicity in female mice and …

Acetaminophen Protein Adducts In Hospitalized Children Receiving Multiple Doses Of Acetaminophen., Sibo Jiang, Valvanera Vozmediano, Susan M. Abdel-Rahman, Stephan Schmidt, Laura P. James

Manuscripts, Articles, Book Chapters and Other Papers

Previous reports have questioned the safety of multiple doses of acetaminophen administered to ill children. Acetaminophen protein adducts (adducts) are a biomarker of acetaminophen-induced liver injury and reflect the oxidative metabolism of acetaminophen, a known mechanism in acetaminophen toxicity. In this prospective observational study, we analyzed adduct concentrations in 1034 blood samples obtained from 181 hospitalized children (1 to 18 years inclusive) who received 2 or more doses of acetaminophen. Linear regression analysis showed that serum adduct concentrations increased as a function of the cumulative acetaminophen dose, which could be attributed, in part, to a long half-life of adducts (2.17 …

Pm, Amal Rammah, Kristina W Whitworth, Inkyu Han, Wenyaw Chan, Elaine Symanski

Journal Articles

There is limited evidence on the role of exposure to chemical constituents of fine particulate matter (PM

Saturated Fatty Acid Activates T Cell Inflammation Through A Nicotinamide Nucleotide Transhydrogenase (Nnt)-Dependent Mechanism, Grace Mccambridge, Madhur Agrawal, Alanna Keady, Philip A. Kern, Hatice Hasturk, Barbara S. Nikolajczyk, Leena P. Bharath

Pharmacology and Nutritional Sciences Faculty Publications

Circulating fatty acids (FAs) increase with obesity and can drive mitochondrial damage and inflammation. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial protein that positively regulates nicotinamide adenine dinucleotide phosphate (NADPH), a key mediator of energy transduction and redox homeostasis. The role that NNT-regulated bioenergetics play in the inflammatory response of immune cells in obesity is untested. Our objective was to determine how free fatty acids (FFAs) regulate inflammation through impacts on mitochondria and redox homeostasis of peripheral blood mononuclear cells (PBMCs). PBMCs from lean subjects were activated with a T cell-specific stimulus in the presence or absence of generally pro-inflammatory …

Rationale, Design And Methods Of "Set The Rules": A Tailored Peer-To-Peer Health Information Intervention, Jennifer R. Warren, Brandi M. White

Health and Clinical Sciences Faculty Publications

Ensuring equitable access to health information is one strategy to promote health equity for underserved communities, especially for low-income African Americans (AAs). Childcare centers are one viable site to deliver health information to address this disparity. This paper describes the methods used in a community-based participatory research project with a childcare facility that aimed to reduce environmental tobacco smoke (ETS) exposure among low-income AA children. Through collaboration and multiple data collection methods, partners identified communication strategies to overcome informational barriers. These initial findings indicated a peer-to-peer health information intervention, entitled “Set the Rules”, as the best strategy to increase awareness. …

Amylin And Diabetic Cardiomyopathy – Amylin-Induced Sarcolemmal Ca2+ Leak Is Independent Of Diabetic Remodeling Of Myocardium, Miao Liu, Amanda Hoskins, Nirmal Verma, Donald M. Bers, Sanda Despa, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

Amylin is a pancreatic β-cell hormone co-secreted with insulin, plays a role in normal glucose homeostasis, and forms amyloid in the pancreatic islets of individuals with type-2 diabetes. Aggregated amylin is also found in blood and extra-pancreatic tissues, including myocardium. Myocardial amylin accumulation is associated with myocyte Ca²⁺ dysregulation in diabetic rats expressing human amylin. Whether deposition of amylin in the heart is a consequence of or a contributor to diabetic cardiomyopathy remains unknown. We used amylin knockout (AKO) mice intravenously infused with either human amylin (i.e, the aggregated form) or non-amyloidogenic (i.e., monomeric) rodent amylin to test the …

Genetic Variants In Hsd17b3, Smad3, And Ipo11 Impact Circulating Lipids In Response To Fenofibrate In Individuals With Type 2 Diabetes, Daniel M. Rotroff, Sonja S. Pijut, Skylar W. Marvel, John R. Jack, Tammy M. Havener, Aurora Pujol, Agatha Schluter, Gregory A. Graf, Henry N. Ginsberg, Hetal S. Shah, He Gao, Mario-Luca Morieri, Alessandro Doria, Josyf C. Mychaleckyi, Howard L. Mcleod, John B. Buse, Michael J. Wagner, Alison A. Motsinger-Reif, Accord/Accordion Investigators

Pharmaceutical Sciences Faculty Publications

Individuals with type 2 diabetes (T2D) and dyslipidemia are at an increased risk of cardiovascular disease. Fibrates are a class of drugs prescribed to treat dyslipidemia, but variation in response has been observed. To evaluate common and rare genetic variants that impact lipid responses to fenofibrate in statin‐treated patients with T2D, we examined lipid changes in response to fenofibrate therapy using a genomewide association study (GWAS). Associations were followed‐up using gene expression studies in mice. Common variants in SMAD3 and IPO11 were marginally associated with lipid changes in black subjects (P < 5 × 10^‐6). Rare variant and gene expression changes …

Constitutive Activation Of Kappa Opioid Receptors At Ventral Tegmental Area Inhibitory Synapses Following Acute Stress., Abigail M Polter, Kelsey Barcomb, Rudy W Chen, Paige M Dingess, Nicholas M Graziane, Travis E Brown, Julie A Kauer

Pharmacology and Physiology Faculty Publications

Stressful experiences potently activate kappa opioid receptors (κORs). κORs in the ventral tegmental area regulate multiple aspects of dopaminergic and non-dopaminergic cell function. Here we show that at GABAergic synapses on rat VTA dopamine neurons, a single exposure to a brief cold-water swim stress induces prolonged activation of κORs. This is mediated by activation of the receptor during the stressor followed by a persistent, ligand-independent constitutive activation of the κOR itself. This lasting change in function is not seen at κORs at neighboring excitatory synapses, suggesting distinct time courses and mechanisms of regulation of different subsets of κORs. We also …

Sex Differences In The Subjective Effects Of Oral Δ9-Thc In Cannabis Users, Jessica S. Fogel, Thomas H. Kelly, Philip M. Westgate, Joshua A. Lile

Behavioral Science Faculty Publications

Previous studies suggest that there are sex differences in endocannabinoid function and the response to exogenous cannabinoids, though data from clinical studies comparing acute cannabinoid effects in men and women under controlled laboratory conditions are limited. To further explore these potential differences, data from 30 cannabis users (N=18 M, 12 F) who completed previous Δ⁹-tetrahydrocannabinol (Δ⁹-THC) discrimination studies were combined for this retrospective analysis. In each study, subjects learned to discriminate between oral Δ⁹-THC and placebo and then received a range of Δ⁹-THC doses (0, 5, 15 and a “high” dose of …

Extracorporeal Membrane Oxygenation (Ecmo) For Severe Toxicological Exposures: Review Of The Toxicology Investigators Consortium (Toxic)., G S. Wang, R Levitan, T J. Wiegand, Jennifer Lowry, R F. Schult, S Yin, Toxicology Investigators Consortium

Manuscripts, Articles, Book Chapters and Other Papers

Although there have been many developments related to specific strategies for treating patients after poisoning exposures, the mainstay of therapy remains symptomatic and supportive care. One of the most aggressive supportive modalities is extracorporeal membrane oxygenation (ECMO). Our goal was to describe the use of ECMO for toxicological exposures reported to the American College of Medical Toxicology (ACMT) Toxicology Investigators Consortium (ToxIC). We performed a retrospective review of the ACMT ToxIC Registry from January 1, 2010 to December 31, 2013. Inclusion criteria included patients aged 0 to 89 years, evaluated between January 2010 through December 2013, and received ECMO for …

Dietary Supplementation With Organoselenium Accelerates Recovery Of Bladder Expression, But Does Not Improve Locomotor Function, Following Spinal Cord Injury, Carolyn A. Meyer, Ranjana Singh, Mackenzie T. Jones, Chen-Guang Yu, Ronan F. Power, James W. Geddes

Spinal Cord and Brain Injury Research Center Faculty Publications

Selenium is an essential element required for activity of several antioxidant enzymes, including glutathione peroxidase. Because of the critical role of the antioxidant system in responding to traumatic events, we hypothesized that dietary selenium supplementation would enhance neuroprotection in a rodent model of spinal cord injury. Rats were maintained on either a control or selenium-enriched diet prior to, and following, injury. Dietary selenium supplementation, provided as selenized yeast added to normal rat chow, resulted in a doubling of selenium levels in the spinal cord. Dietary selenium reduced the time required for recovery of bladder function following thoracic spinal cord injury. …

Chronic Ethanol Exposure Enhances The Aggressiveness Of Breast Cancer: The Role Of P38Γ, Mei Xu, Siying Wang, Zhenhua Ren, Jacqueline A. Frank, Xiuwei H. Yang, Zhuo Zhang, Zun-Ji Ke, Xianglin Shi, Jia Luo

Pharmacology and Nutritional Sciences Faculty Publications

Both epidemiological and experimental studies suggest that ethanol may enhance aggressiveness of breast cancer. We have previously demonstrated that short term exposure to ethanol (12–48 hours) increased migration/invasion in breast cancer cells overexpressing ErbB2, but not in breast cancer cells with low expression of ErbB2, such as MCF7, BT20 and T47D breast cancer cells. In this study, we showed that chronic ethanol exposure transformed breast cancer cells that were not responsive to short term ethanol treatment to a more aggressive phenotype. Chronic ethanol exposure (10 days - 2 months) at 100 (22 mM) or 200 mg/dl (44 mM) caused the …

Blood Pressure Changes In Relation To Arsenic Exposure In A U.S. Pregnancy Cohort, Shohreh F. Farzan, Yu Chen, Fen Wu, Jieying Jiang, Mengling Liu, Emily Baker, Susan A. Korrick, Margaret R. Karagas

Dartmouth Scholarship

Background:

Inorganic arsenic exposure has been related to the risk of increased blood pressure based largely on cross-sectional studies conducted in highly exposed populations. Pregnancy is a period of particular vulnerability to environmental insults. However, little is known about the cardiovascular impacts of arsenic exposure during pregnancy.

Objectives:

We evaluated the association between prenatal arsenic exposure and maternal blood pressure over the course of pregnancy in a U.S. population.

Methods:

The New Hampshire Birth Cohort Study is an ongoing prospective cohort study in which > 10% of participant household wells exceed the arsenic maximum contaminant level of 10 μg/L established by …

Association Between Arsenic Exposure From Drinking Water And Longitudinal Change In Blood Pressure Among Heals Cohort Participants, Jieying Jiang, Mengling Liu, Faruque Parvez, Binhuan Wang, Fen Wu, Mahbub Eunus, Sripal Bangalore, Jonathan D. Newman, Alauddin Ahmed, Tariqul Islam, Muhammed Rakibuz-Zaman, Rabiul Hasan, Golam Sarwar, Diane Levy, Vesna Slavkovich, Maria Argos, Molly Scannell Bryan, Shohreh F. Farzan, Richard B. Hayes, Joseph H. Graziano, Habibul Ahsan, Yu Chen

Dartmouth Scholarship

Background:

Cross-sectional studies have shown associations between arsenic exposure and prevalence of high blood pressure; however, studies examining the relationship of arsenic exposure with longitudinal changes in blood pressure are lacking.

Method:

We evaluated associations of arsenic exposure in relation to longitudinal change in blood pressure in 10,853 participants in the Health Effects of Arsenic Longitudinal Study (HEALS). Arsenic was measured in well water and in urine samples at baseline and in urine samples every 2 years after baseline. Mixed-effect models were used to estimate the association of baseline well and urinary creatinine-adjusted arsenic with annual change in blood pressure …

Placental Dna Methylation Related To Both Infant Toenail Mercury And Adverse Neurobehavioral Outcomes, Jennifer Zeynab Joukhadar Maccani, Devin C. Koestler, Barry Lester, E Andres Houseman, David A. Armstrong, Karl T. Kelsey, Carmen J. Marsit

Dartmouth Scholarship

Background:

Prenatal mercury (Hg) exposure is associated with adverse child neurobehavioral outcomes. Because Hg can interfere with placental functioning and cross the placenta to target the fetal brain, prenatal Hg exposure can inhibit fetal growth and development directly and indirectly.

Objectives:

We examined potential associations between prenatal Hg exposure assessed through infant toenail Hg, placental DNA methylation changes, and newborn neurobehavioral outcomes.

Methods:

The methylation status of > 485,000 CpG loci was interrogated in 192 placental samples using Illumina’s Infinium HumanMethylation450 BeadArray. Hg concentrations were analyzed in toenail clippings from a subset of 41 infants; neurobehavior was assessed using the NICU …

Cd151-Α3Β1 Integrin Complexes Suppress Ovarian Tumor Growth By Repressing Slug-Mediated Emt And Canonical Wnt Signaling, Lauren A. Baldwin, John T. Hoff, Jason Lefringhouse, Michael Zhang, Changhe Jia, Zeyi Liu, Sonia Erfani, Hongyan Jin, Mei Xu, Qing-Bai She, John R. Van Nagell Jr., Chi Wang, Li Chen, Rina Plattner, David M. Kaetzel, Jia Luo, Michael Lu, Dava West, Chunming Liu, Fred R. Ueland, Ronny Drapkin, Binhua P. Zhou, Xiuwei H. Yang

Pharmacology and Nutritional Sciences Faculty Publications

Human ovarian cancer is diagnosed in the late, metastatic stages but the underlying mechanisms remain poorly understood. We report a surprising functional link between CD151-α3β1 integrin complexes and the malignancy of serous-type ovarian cancer. Analyses of clinical specimens indicate that CD151 expression is significantly reduced or diminished in 90% of metastatic lesions, while it remains detectable in 58% of primary tumors. These observations suggest a putative tumor-suppressing role of CD151 in ovarian cancer. Indeed, our analyses show that knocking down CD151 or α3 integrin enhances tumor cell proliferation, growth and ascites production in nude mice. These changes are accompanied by …

Health Disparities Experienced By People With Disabilities In The Us: A Behavioral Risk Factor Surveillance System Study, Jennifer Renee Pharr, Timothy J. Bungum

Environmental & Occupational Health Faculty Publications

The Americans with Disabilities Act became law in 1990; since then research has shown that people with disabilities continue to experience barriers to health care. The purpose of this study was to compare utilization of preventive services, chronic disease rates, and engagement in health risk behaviors of participants with differing severities of disabilities to those without disabilities. This study was a secondary analysis of 2010 data collected in the Behavioral Risk Factor Surveillance System national survey in the United States. Rao Chi square test and logistic regression were employed. Participants with disabilities had significantly higher adjusted odds ratios for all …

Specific Thiazolidinediones Inhibit Ovarian Cancer Cell Line Proliferation And Cause Cell Cycle Arrest In A Pparγ Independent Manner, Linah Al-Alem, R. Chase Southard, Michael W. Kilgore, Thomas E. Curry

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: Peroxisome Proliferator Activated Receptor gamma (PPARγ) agonists, such as the thiazolinediones (TZDs), have been studied for their potential use as cancer therapeutic agents. We investigated the effect of four TZDs--Rosiglitazone (Rosi), Ciglitazone (CGZ), Troglitazone (TGZ), and Pioglitazone (Pio)--on ovarian cancer cell proliferation, PPARγ expression and PPAR luciferase reporter activity. We explored whether TZDs act in a PPARγ dependent or independent manner by utilizing molecular approaches to inhibit or overexpress PPARγ activity.

PRINCIPAL FINDINGS: Treatment with CGZ or TGZ for 24 hours decreased proliferation in three ovarian cancer cell lines, Ovcar3, CaOv3, and Skov3, whereas Rosi and Pio had no …

Arsenic Exposure Is Associated With Decreased Dna Repair In Vitro And In Individuals Exposed To Drinking Water Arsenic, Angeline S. Andrew, Jefferey L. Burgess, Maria M. Meza, Eugene Demidenko, Mary G. Waugh, Joshua W. Hamilton, Margaret R. Karagas

Dartmouth Scholarship

The mechanism(s) by which arsenic exposure contributes to human cancer risk is unknown; however, several indirect cocarcinogenesis mechanisms have been proposed. Many studies support the role of As in altering one or more DNA repair processes. In the present study we used individual-level exposure data and biologic samples to investigate the effects of As exposure on nucleotide excision repair in two study populations, focusing on the excision repair cross-complement 1 (ERCC1) component. We measured drinking water, urinary, or toenail As levels and obtained cryopreserved lymphocytes of a subset of individuals enrolled in epidemiologic studies in New Hampshire (USA) and Sonora …