About

Nancy Fiedler, Ph.D., is the Deputy Director and a Professor at the Environmental and Occupational Health Sciences Institute (EOHSI) at Rutgers University – School of Public Health. Her research focuses on controlled human exposure health effects studies, incorporating chemical exposures and psychological stress to model realistic environmental exposures. She conducts epidemiologic investigations of toxic encephalopathy among workers chronically exposed to solvents and lead, with a focus on integrating neuropsychological testing, exposure assessment, and functional imaging. Her translational research examines whether alterations in hypothalamic-pituitary-adrenal (HPA) axis function among lead-exposed animals translate to humans with similar exposures. Dr. Fiedler is involved in international studies based in Thailand investigating the cognitive and behavioral effects of pesticide exposure in a birth cohort.

Research topics

• Medicine
• Psychology
• Environmental health
• Toxicology
• Psychiatry

Selected publications

• Geospatial insights of health vulnerability during the Ukraine war

  Nature Health · 2026-02-12

  article
  PublisherDOI

• The Quality of the Home Environment During the First 2 Years of Life and Cognitive Development in Early Childhood: A Study of Thai Agricultural Families

  Child Care Health and Development · 2026-02-17

  article

  BACKGROUND: Research globally has highlighted the crucial role of the early-life home environment in shaping children's long-term development. We examined changes in the quality of the home environment during infancy and its associations with child cognitive development at age 3, focusing on Thai children from socioeconomically disadvantaged families. METHODS: Two-hundred and eighty mother-child dyads from a Thai birth cohort completed home visits in which demographic data were collected and the IT-HOME interview completed when the child was 1 and 2 years old. The Bayley-III cognitive scale was administered at 3 years old. RESULTS: Our regression analysis revealed significant associations between the quality of the home environment at 2 years (B = 0.30, SE = 0.14, p = 0.028, 95% CI: [0.03, 0.56]), but not 1 year (B = 0.11, SE = 0.11, p = 0.279, 95% CI: [-0.09, 0.32]), and cognitive development at 3 years. Furthermore, positive changes in the quality of the home environment from 1 to 2 years were significantly associated with better cognitive development (B = 0.30, SE = 0.14, p = 0.028, 95% CI: [0.03, 0.56]). CONCLUSION: Our results underscore the importance of both the immediate quality of the home environment and its improvements over time. We suggest that future studies expand to include more diverse demographic backgrounds within Thai culture and across different cultures, collect data over a longer period to capture associations at older ages, and develop targeted interventions to further understand and improve child cognitive development through an optimal home environment.

  PublisherDOI

• Sex- and Trimester-Specific Placental Transcriptomic Responses to Prenatal Organophosphate and Pyrethroid Mixtures and Their Associations with Neonatal Growth

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• Prenatal pyrethroid exposure, placental gene network modules, and neonatal neurobehavior

  International Journal of Hygiene and Environmental Health · 2025-08-01

  articleOpen access

  Prenatal pesticide exposure may adversely affect child neurodevelopment which may partly arise from impairing the placenta's vital role in fetal development. In a cohort of pregnant farmworkers from Thailand (N = 248), we examined the links between urinary metabolites of pyrethroid pesticides during pregnancy, placental gene expression networks derived from transcriptome sequencing, and newborn neurobehavior assessed using the NICU Network Neurobehavioral Scales (NNNS) at 5 weeks of age. Focusing on the 21 gene network modules in the placenta identified by Weighted Gene Co-expression Network Analysis, our analysis revealed significant associations between metabolites and nine distinct modules, and between thirteen modules and NNNS, with eight modules showing overlap. Notably, stress was negatively associated with the interferon alpha response and Myc target modules, and the interferon alpha response module was correlated positively with attention, and negatively with arousal, and quality of movement. The analysis also highlighted the early and late trimesters as critical periods for the exposures influence on placental function, with pyrethroid metabolites measured early in pregnancy significantly negatively associated with the protein secretion module, and those measured later in pregnancy negatively associated with modules related to oxidative phosphorylation (OXPHOS) and DNA repair. Additionally, the cumulative sum of 3-phenoxybenzoic acid across pregnancy was significantly negatively associated with the OXPHOS module. These findings suggest that prenatal exposure to pyrethroids may influence neonatal neurobehavior through specific placental mechanisms that impact gene expression of metabolic pathways, and these effects may be pregnancy period specific. These results offer valuable insights for future risk assessment and intervention strategies.

  PublisherDOI

• Machine learning reveals drivers of cold-related illness during energy infrastructure attacks in Wartime Ukraine

  Scientific Reports · 2025-12-31 · 1 citations

  articleOpen access

  During the Russian invasion of Ukraine, targeted attacks on energy infrastructure exposed civilians to heightened cold-related health risks. This study aimed to: (1) characterize respiratory infections and cold-related injuries during the conflict; (2) identify vulnerable sociodemographic groups; (3) assess household adaptations; and (4) evaluate how winter preparation influenced health outcomes. We surveyed 2311 households across 24 Ukrainian oblasts during the winter of 2022–2023. One adult per household provided data on demographics, winter preparations, housing, heating, and access to services. Machine learning models were used to predict respiratory infections, symptoms, and cold injuries, based on sociodemographic and household factors. Respiratory infections affected 75.2% of participants, and 3.76% reported cold injuries, rising to 10% among older adults. Larger households experienced more respiratory infections, while areas under Russian control reported higher rates of cold injury. Key predictors of respiratory infections included age, household size, financial stability, and heating practices; cold injuries were predicted by age, region, anxiety, and household size. This is the first study to apply machine learning in examining the health impacts of cold-related events following energy infrastructure attacks in an active conflict zone. Our findings underscore the vulnerability of older adults and the widespread burden of respiratory infections, highlighting the need for targeted cold injury prevention in conflict-affected and cold-climate regions.

  PublisherOA PDFDOI

• Winter’s Toll: Assessing the Public Health Impact of Cold-Related Illnesses and Energy Damage in Ukraine During the Invasion

  Research Square · 2025-06-04 · 1 citations

  preprintOpen access
  PublisherOA PDFDOI

• Human Nervous System and Behavioral Toxicology

  Elsevier eBooks · 2025-04-05

  book-chapter1st authorCorresponding
  PublisherDOI

• Parent-child mental health in Ukraine in relation to war trauma and drone attacks

  Comprehensive Psychiatry · 2025-03-10 · 6 citations

  articleOpen access

  We aimed to address the knowledge gap regarding mental health in Ukrainian children and parents one year after Russia's 2022 full-scale invasion including associations with exposure to drone attacks. A cross-sectional, quota-sampled survey was conducted among parents of children aged 3–17 in Ukraine one year after the invasion ( n = 858). Participants completed self-reported screening measures of the Pediatric Symptom Checklist-17, Child and Adolescent Trauma Screen–Caregiver, Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, the International Trauma Questionnaire, and the University of California, Los Angeles (UCLA) 3-Item Loneliness Scale. We analyzed scores in relation to drone attack exposure using logistic regression. Many children aged 3–6 years had scores suggestive of ADHD (24.2 %), conduct disorder (20.5 %), and anxiety/mood disorder (12.1 %). Results were similar among children aged 7–17 (anxiety/mood disorder: 24.1 %, conduct disorder: 14.5 %, and ADHD: 14 %). Of the 45.0 % of children aged 3–6 and 57.0 % aged 7–17 exposed to post-invasion trauma, 21.8 % and 17.6 % had clinically relevant levels of PTSD symptoms, respectively. Parental symptoms met screening criteria for depressive disorder in 46.7 % and for anxiety disorder in 24.2 %. All parents reported post-invasion trauma, with 24.5 % screening positive for PTSD. Child mental health disorder odds increased with parental PTSD (OR 1.85, 95 %CI 1.29–2.72) and symptoms meeting screening criteria for depressive disorder (OR 1.99, 95 %CI 1.15–2.56). The odds of children aged 7–17 having clinically relevant levels of PTSD symptoms increased with parental symptoms screening positive for depressive disorder (OR 6.0, 95 %CI 2.0–18.3), anxiety disorder (OR 3.48, 95 %CI 1.76–6.8), and PTSD (OR 3.23, 95 % 1.67–6.2). Parents had a higher prevalence of screening positive for PTSD in high-intensity drone attack regions (28.9 %) than low- and moderate-intensity regions (25.0 % and 20.5 %, respectively, p = 0.04). The high prevalence of children and parents in Ukraine with symptoms screening positive for mental disorders indicates an urgent need for services for school-age children and parents in this war-affected region. High-intensity drone attacks increase the risk of parents screening positive for PTSD. • Identified significantly higher PTSD rates among parents in high-intensity drone attack regions compared to broader adult populations in Ukraine. • Parental PTSD, depression, and loneliness strongly predict mental health disorders in children aged 7–17. • Highlights the interconnected mental health impact of war within family units • Highlights the necessity for systematic research on drone warfare's mental health effects on civilian populations • Advocates for cessation of drone attacks on civilians and focused mental health interventions for those exposed to high-intensity trauma.

  PublisherDOI

• Abstract 4366004: Placental Epigenetic Signatures of Prenatal Pesticide Exposure and Fetal Growth: Insights into Cardiometabolic Programming

  Circulation · 2025-11-03

  article

  Prenatal exposure to pesticides has been linked to disrupted fetal growth, which contributes to cardiometabolic disease risk. The placenta, as the maternal–fetal interface, undergoes extensive DNA methylation remodeling that may record environmental exposures and mediate downstream metabolic effects, including those related to cardiometabolic risk in offspring. We hypothesized that placental DNA methylation patterns vary with maternal pesticide exposure, that exposure-associated CpG sites overlap with those predictive of neonatal anthropometry, and that genes with altered methylation may represent pathways relevant to cardiometabolic health. We analyzed 254 term placentas from the Study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) cohort using the Illumina EPIC v2.0 array. Robust linear regression models assessed associations between placental DNA methylation and infant head circumference, birth length, and birth weight z-scores. Each outcome was analyzed separately, adjusting for estimated proportions of eight placental cell types, infant sex, maternal age, BMI, and gestational age. Parallel analyses examined urinary organophosphate metabolites (OP), pyrethroid metabolites (PYR), and a composite exposure index (MIX). CpGs with Benjamini–Hochberg FDR < 0.05 were considered significant. Significant CpGs were intersected across exposures and outcomes and mapped to genes for Gene Ontology and KEGG pathway enrichment (FDR < 0.05). EWAS of growth traits identified 26, 1,626, and 1,729 CpGs associated with head circumference, birth length, and birthweight, respectively. CpGs associated with weight and length were enriched for pathways including insulin resistance and MAPK signaling. Exposure-related EWAS identified 46,519 significant CpGs for OP and 46,564 for MIX; none for PYR. MAPK signaling was the top enriched pathway for both OP and MIX. Intersection of OP and MIX signatures yielded 46,417 shared CpGs, with 102 and 135 overlapping length- and weight-associated sites, respectively. Nine genes were common to both exposure and growth signatures, with IRS1 identified as a central node linking insulin and MAPK pathways. Placental methylation patterns associated with prenatal pesticide exposure overlap with epigenetic signals linked to neonatal growth, particularly involving insulin resistance and MAPK signaling, highlighting mechanisms of fetal programming relevant to long-term cardiometabolic health.

  PublisherDOI

• A birth cohort observational study to assess the association of prenatal biomarkers of organophosphates with visual attention, recognition memory and information processing among Thai infants

  Environmental Research · 2025-02-28 · 1 citations

  articleOpen access1st authorCorresponding

  BACKGROUND: Organophosphates (OPs) are neurotoxicants used to control pests on crops (e.g., rice). Thai women farmworkers (∼23%) may be exposed during childbearing years. Previous literature documents adverse neurodevelopmental effects of prenatal exposure to pesticides although findings are inconsistent. OBJECTIVE: We evaluated the associations of prenatal OPs with measures of attention, memory, and information processing. METHODS: We recruited 323 mother/infant pairs and analyzed maternal urine for OPs (∑DAPs) during each trimester of pregnancy. Infants completed computerized tests of visual habituation (VH) (attention), visual paired comparison (VPC) (recognition memory), and continuous performance (CFT) (information processing). Adjusted regression models associated maternal biomarkers with infant measures. RESULTS: We did not find adverse effects of ∑DAPs associated with VH at 4 or 7 months. However, males in the highest relative to lowest tertile of 2nd trimester ∑DAPs did not exhibit the expected decline in speed of VH from 4 to 7 months. Overall ∑DAPs at 7 and 18 months were negatively associated with VPC for males and females with strongest associations for females. CFT trials to criterion were positively associated with ∑DAPs at 12 and 18 months particularly for males at 18 months, suggesting slower encoding. However, females achieved better performance on visual habituation and continuous familiarization associated with higher maternal ∑DAPs at 4 and 7 months, respectively. We also observed better performance for VPC among males and females at 12 months. DISCUSSION: Because infant visual attention, recognition memory, and information processing are predictive of later cognitive development such as emerging executive function, alterations associated with prenatal OPs could have long-term consequences for school readiness.

  PublisherDOI

Recent grants

• NIH Grant R01OH003691

  NIH · $1.3M · 2003

• NIH Grant R21ES015135

  NIH · $700k · 2010

• NIH Grant R21ES018722

  NIH · $287k · 2013

• Impact of prenatal insecticide exposure on neurodevelopmental trajectories in a Thai birth cohort: building exposure science and neurodevelopmental research capacity in Thailand

  NIH · $3.1M · 2016–2023

• NIH Grant R01OH008198

  NIH · $2.2M · 2009

Frequent coauthors

• Howard M. Kipen

  Rutgers, The State University of New Jersey

  153 shared

• Pamela Ohman‐Strickland

  Rutgers, The State University of New Jersey

  111 shared

• Clifford P. Weisel

  78 shared

• Robert Laumbach

  Rutgers Health

  73 shared

• Gudrun Lange

  57 shared

• Kathie Kelly‐McNeil

  National Institute of Environmental Health Sciences

  50 shared

• Chizoba Nwankwo

  50 shared

• Mark G. Robson

  Rutgers, The State University of New Jersey

  43 shared

Education

• Ph.D., Clinical Psychology

  Bowling Green State University

Awards & honors

• NIH Fogarty International Center Grant reviewer
• Co-Chair for the New Jersey Alliance for Clinical and Transl…
• EOHSI representative for the RBHS Mentor Committee