Prenatal mercury (Hg) exposure was determined in a sub-cohort of the Caribbean Consortium for Environmental and Occupational Health’s environmental epidemiologic prospective cohort study of pregnant women living in Suriname’s interior. The associations between Hg exposure, low birth weight (LBW, <2500 g) and preterm birth (PTB, <37 weeks) were explored. Correlation analysis, Fisher’s exact test and logistic regression analyses were conducted to evaluate the associations between maternal hair Hg levels and birth weight, LBW and PTB, and between potential confounders, LBW and PTB, respectively. Among 204 singleton births were 198 live births, five stillbirths and one miscarriage. The mean participant age was 26 years; 15.7% of participants had PTBs and 8.1% delivered a child with a LBW. The median hair Hg level was 3.48 μg/g hair. Low hair Hg exposure, based on lowest tertile < 2.34 μg/g, was associated with LBW (OR = 7.2; 95% CI 1.5–35.6; p = 0.015); this association was independent of maternal age, ethnic background, household income and village location, and no correlation was found between hair Hg and PTB. Young maternal age was associated with PTB (RR = 5.09, 95% CI: 1.92–13.85; p = 0.0004) while maternal age was not associated with hair Hg or LBW. The impact of prenatal Hg exposure on pediatric neurodevelopment is currently being evaluated in the infant sub-cohort.

Background: Adequate antenatal care (ANC) services are key for early identification of pregnancy related risk factors and maintaining women’s health during pregnancy. This study aimed to assess the influence of ANC provided by the Medical Mission Primary Health Care Suriname (MMPHCS) and of ethnicity on adverse birth outcomes in Tribal and Indigenous women living in Suriname’s remote tropical rainforest interior. Method: From April 2017 to December 2018 eligible Tribal and Indigenous women with a singleton pregnancy that received ANC from MMPHCS were included in the study. Data on low birth weight (LBW < 2500 g), preterm birth (PTB < 37 weeks), low Apgar score (< 7 at 5 min), parity (≤1 vs. > 1) and antenatal visits utilization (≥8 vs. < 8) in 15 interior communities were retrospectively analyzed using descriptive statistics, crosstabs and Fisher’s exact tests. Results: A total of 204 women were included, 100 (49%) were Tribal, mean age was 26 ± 7.2 years and 126 women (62%) had 8 or more ANC visits. One participant had a miscarriage; 22% had adverse birth outcomes: 16 (7.9%) LBW and 30 (14.8%) PTB; 7 women had a child with both PTB and LBW; 5 women had stillbirths. None of the newborns had low Apgar scores. Maternal age, ethnicity, ANC and parity were associated with PTB (χ² = 8,75, p = 0.003, χ² = 4,97, p = 0.025, χ² = 17,45, p < 0.001, χ² = 11,93, p < 0.001 respectively). Conclusion: Despite an almost 100% study adherence over one fifth of women that received ANC in the interior of Suriname had adverse birth outcomes, in particular PTB and LBW. Younger nulliparous Indigenous women with less than the recommended 8 ANC visits had a higher risk for PTB. The rate of adverse birth outcomes highlights the need for further research to better assess factors influencing perinatal outcomes and to put strategies in place to improve perinatal outcomes. Exposure assessment of this sub-cohort and neurodevelopment testing of their children is ongoing and will further inform on potential adverse health effects associated with environmental exposures including heavy metals such as mercury and lead.

Information regarding adverse birth outcomes (ABO) of Indigenous and Tribal women living in the remote tropical rainforest of Suriname, where mercury (Hg) use is abundant in artisanal gold mining, is not available. In the context of a health system analysis, we examined the association between Hg exposure, maternal sociodemographics on the ABO of Indigenous and Tribal women living in Suriname’s interior and its capital, Paramaribo. ABO were determined in pregnant women enrolled from December 2016 to July 2019 in the Caribbean Consortium for Environmental and Occupational Health prospective environmental epidemiologic cohort study. Associations were explored using Pearson’s χ²-test and the Mann–Whitney U-test. Among 351 singleton participants, 32% were Indigenous, residing mainly in the interior (86.8%), and 23.1% had ABO. Indigenous participants had higher rates of ABO (29.8% vs. 19.8%) and preterm birth (PTB) (21.2% vs. 12.4%), higher Hg levels, delivered at a younger age, were less educated, and had lower household income compared to Tribal participants. Multivariate logistic regression models revealed that Indigenous participants had higher odds of ABO (OR = 3.60; 95% CI 1.70–7.63) and PTB (OR = 3.43; 95% CI 1.48–7.96) compared with Tribal participants, independent of Hg exposure and age at delivery. These results highlight the importance of effective risk reduction measures in support of Indigenous mothers, families, and communities.

Background: Lead (Pb) exposure remains a major global health issue, and Pb stable isotope ratio analysis is a powerful tool for identifying potential exposure sources. However, traditional whole blood collection is difficult to implement in remote or resource-limited settings. We developed and validated a novel method for measuring Pb isotopic composition in dried blood spots (DBS) using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) and applied it in a pilot study of DBS collected from children in Suriname, South America. Methods: Method accuracy was evaluated by comparing isotopic ratios (²⁰⁸Pb/²⁰⁶Pb and ²⁰⁷Pb/²⁰⁶Pb) measured in laboratory-spiked DBS (15 µL of blood per DBS) with those from matched whole blood samples (1 mL) across a range of Pb concentrations (2.1–28.9 µg/dL). The method was then applied to DBS collected from 18 children, ages 6 months to 5 years, in Suriname. Potential local exposure sources, including soil, shotgun pellets, and cooking utensils, were also analyzed for lead isotopic composition and compared with DBS isotope ratios to assess source concordance. Results: DBS isotopic ratios accurately reflected whole blood values when Pb concentrations exceeded ~315 pg/punch (~2.1 µg/dL), with greater accuracy observed above 5 µg/dL. In the Suriname DBSs, blank-corrected ²⁰⁸Pb/²⁰⁶Pb ratios were consistent across regions (mean 2.12 ± 0.018; n = 15) and showed no significant geographic stratification (p = 0.11). DBS signatures (isotope ratios) most closely aligned with shotgun pellets and soil samples, whereas those from cooking utensils did not match DBS signatures. A positive correlation was observed between estimated blood total Pb and soil Pb concentrations (ρ = 0.60, p = 0.20). Conclusions: Overall, DBS provided reliable Pb isotopic ratio measurements above ~2–5 µg/dL, spanning the current CDC reference value of 3.5 µg/dL at which children’s exposures warrant investigation. These findings support DBS as a minimally invasive, scalable tool for exposure source identification in environmental epidemiology, particularly in remote settings where traditional venipuncture is impractical. What this study adds: This study establishes the first validated method for high-precision lead (Pb) stable isotopic ratio analysis using dried blood spots (DBS). By implementing a sample blank correction, we demonstrate that DBS can accurately resolve isotopic signatures even at low blood lead concentrations. Applied in DBS collected in Suriname, the method successfully linked DBS signatures to local shotgun pellets and soils, illustrating a common exposure profile across diverse regions. This work expands the utility of DBS beyond simple screening, offering a minimally invasive, scalable tool for source attribution in global health research and environmental epidemiology in remote regions.