Serum NO₃⁻ and NO₂⁻ levels among pregnant women from agricultural communities: associations with self-reported dietary and environmental exposures.

Mercury Levels and Their Determinants in Women of Reproductive Age in the Brazilian Amazon: A Cross-Sectional Study

Mercury exposure remains a public health concern in Amazonian populations. This study assessed hair total mercury levels and associated determinants in 205 women of reproductive age from riverine communities in the Lower Tocantins and Xingu regions, Pará,Brazil. Hair Hg concentrations were measured using cold vapor atomic absorption spectrometry. Multivariable linear regression was used to identify predictors of log-transformed mercury total levels. Median concentration was 0.332 µg/g, with 85.4% below 1 µg/g. Women from the Lower Tocantins had significantly higher levels than those from the Xingu (p < 0.001). Region (β = −0.516; p < 0.001) and high fish consumption (> 4 times/week; β = 0.207; p = 0.024) were significant predictors. Mercury levels were low, but regional differences and high fish consumption frequency were associated with exposure, highlighting the need for targeted biomonitoring strategies.

Insights into Environmental Mercury Exposure Based on Biomonitoring of 150 Women of Reproductive Age

Geographic and Environmental Differences in Associations Between Food Insecurity and Nutritional and Inflammatory Biomarkers Among Pregnant Participants in the All of Us Research Program

Background/Objectives: Food insecurity (FI) affects a substantial proportion of pregnant individuals in the United States and varies across geographic contexts. Rural and urban communities differ in food access, socioeconomic conditions, and environmental exposures, yet how these differences relate to maternal biology remain misunderstood. Methods: This study examined associations between FI, geographic context, and metabolic, nutritional, and inflammatory biomarkers among pregnant participants in the Southeastern United States (SE-US) using data from the All of Us (AoU) Research Program. Survey, clinical, and laboratory data were integrated with ZIP3-level geographic and food environment indicators. Analyses were conducted using biomarker-specific complete-case cohorts and multivariable regression models. Results: This study found that FI was more prevalent among rural participants than urban participants. However, in the overall cohort, FI was associated with higher body mass index, higher non-fasting glucose, higher C-reactive protein, and lower high-density lipoprotein cholesterol. Pregnant food-insecure participants also exhibited lower concentrations of vitamin B12, albumin, vitamin D, and folate, while ferritin did not differ. Stratified analyses demonstrated variability in these associations by urbanicity, with stronger and more consistent differences observed in urban populations and fewer significant differences in rural settings. Conclusions: Limitations of this study include potential residual confounding, EHR-related selection bias, exposure misclassification, and limited generalizability. Despite the limitations, recent self-reported household FI, assessed at enrollment and referring to the preceding 12 months, was associated with differences in several metabolic and nutritional biomarkers, with patterns varying by geographic context. Further longitudinal research is needed to clarify these associations and inform targeted interventions.

Prevalence and associated factors of meeting minimum dietary diversity for women among pregnant and non-pregnant women of reproductive age in three sub-Saharan African countries

Introduction: Food insecurity and undernutrition persist in much of sub-Saharan Africa. Women of reproductive age (WRA) who fail to meet the minimum dietary diversity (MDD-W) have inadequate nutrient intakes and increased risk of adverse pregnancy outcomes. This study assessed MDD-W in The Gambia, Kenya, and Mozambique and identified determinants. Methods: A food list-based 24-hour recall was conducted within the PRECISE Network, a prospective cohort study with pregnant and non-pregnant WRA in The Gambia, Kenya, and Mozambique. We descriptively summarized dietary diversity scores and rates of MDD-W ([≥]5 out of 10 food groups) and very low dietary diversity ([≤]2 food groups). We evaluated associated factors (demographic/household characteristics, socio-economic status, womens autonomy), using multivariable regression models performed on R Studio (version 4.2.3). Results: Dietary intake data from 7,715 women (1,846 from The Gambia, 3,209 from Kenya, 2,660 from Mozambique) showed that 47.7% met MDD-W (65.1% The Gambia, 45.0% Kenya, 39.2% Mozambique). Pregnant women had a slightly higher rate of meeting MDD-W compared with non-pregnant WRA (48.4% pregnant vs 45.6% non-pregnant [aOR 1.65, 95% CI: 1.40, 1.95]). Higher educational attainment, professional and small business occupations, pregnancy status, parity, household size, marital status and being from The Gambia were protective factors for meeting MDD-W. Poverty and living alone were risk factors for unmet MDD-W. Poverty and country of residence (Mozambique), were risk factors for very low dietary diversity. Conclusion: A majority of the PRECISE cohort did not meet MDD-W, including both pregnant and non-pregnant WRA, suggesting inadequate micronutrient status before pregnancy and limited dietary diversity improvement during pregnancy. Socio-economic indicators are key determinants of adequate dietary diversity, but local contextualisation is essential. Our study highlights the importance of nutrition-specific and -sensitive interventions in women and girls across the lifespan.

Determinants of serum aflatoxin B1 exposure among pregnant women in coastal Kenya: a cross-sectional study in Kwale County

Aflatoxin B1 (AFB1) exposure is a major environmental health concern among vulnerable groups such as pregnant women, yet its determinants in coastal settings remain poorly understood. We aimed to quantify AFB1 exposure and examine its environmental, behavioral, and sociodemographic determinants among pregnant women in Kwale County, a predominantly rural area on Kenya’s southern Indian Ocean coast. In a facility-based cross-sectional study, serum AFB1–albumin adduct concentrations were measured by enzyme-linked immunosorbent assay in 298 pregnant women. Determinants were examined with a pre-specified multivariable linear regression of log-transformed concentrations using heteroscedasticity-consistent (HC3) standard errors, and a secondary Firth penalized logistic model of detectable versus non-detectable exposure. Adducts were detectable in 251 participants (84.2%); the median concentration was 28.1 pg/mL (IQR 13.7–68.7). Exposure was determined primarily by where women lived: it was lowest in the community closest to the coast and progressively higher in two drier, more inland communities (2.02-fold, 95% CI 1.44–2.85; and 3.02-fold, 95% CI 1.89–4.82). Single marital status was associated with modestly higher exposure (1.89-fold; 95% CI 1.17–3.05). Food source, flour storage, maternal education, and age did not predict exposure, and the penalized logistic model reproduced the same geographical pattern. Despite near-universal exposure, only 1.7% of participants had ever heard of aflatoxin. AFB1 exposure was widespread and geographically structured, pointing to place-based rather than individual-level drivers and supporting area-targeted food-safety interventions to protect maternal and fetal health. These findings have implications for food-safety strategies in other tropical regions where climate and subsistence agriculture contribute to chronic aflatoxin exposure.

Association Between Serum Cotinine Concentrations and Depression Among U.S. Adults: NHANES 2005-2018.

Background: Evidence on the association between objective measures of tobacco exposure and depression remains limited. This study examined the relationship between serum cotinine and depression in a nationally representative U.S. population. Methods: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Serum cotinine was analyzed as a biomarker of nicotine exposure. Depression was defined as a Patient Health Questionnaire-9 (PHQ-9) score ≥10. Weighted logistic regression and restricted cubic spline models were used to assess linear and nonlinear associations. Subgroup and sensitivity analyses were also performed. Results: A total of 29,514 participants were included. Serum cotinine concentrations were positively associated with depression. Each one-unit increase in log-transformed cotinine was associated with higher odds of depression (OR = 1.07, 95% CI: 1.06-1.09). Compared with the lowest tertile, participants in the highest tertile had increased odds of depression (OR = 1.72, 95% CI: 1.45-2.04). Restricted cubic spline analysis indicated a linear association between log-transformed serum cotinine concentrations and depression after excluding participants with serum cotinine concentrations at the lower limit of detection. The association remained robust after additional adjustment for smoking status (OR = 1.05, 95% CI: 1.03-1.07) and subgroup analyses. Conclusions: Serum cotinine concentrations were positively associated with depression in a nationally representative U.S. population. These findings suggest a potential link between nicotine exposure and depression and underscore the importance of further investigating the relationship between tobacco exposure and mental health.