Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) Cohort Study: influences of complex environmental exposures on maternal and child health in Suriname

Association between Liver and Kidney Function and Birth Outcomes in Pregnant Surinamese Women Exposed to Mercury and Lead in the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) Environmental Epidemiologic Cohort Study

Exposure to mercury (Hg) and lead (Pb), in combination with liver and kidney impairment, may result in adverse birth outcomes. From 408 women in the age range of 16 to 46 years, living in rural and urban areas in the interior of Suriname, we looked at the association between adverse birth outcomes and exposure to Hg and Pb in combination with liver and kidney function. This group of women represented a subcohort of pregnant women who participated in the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH)-Meki Tamara study. Liver function was assessed by measuring aspartate amino transferase (AST), alanine amino transferase (ALT), and gamma-glutamyl transferase (GGT). Kidney function was assessed by measuring creatinine, urea, and cystatin C. We defined preterm births as birth before 37 weeks of gestation, low birthweight as birthweight < 2500 g, and low Apgar score as a score < 7 at 5 min, and these were used as indicators for adverse birth outcomes. Small size for gestational age was defined as gestational age < -2SD weight for GA. We found significant statistical associations between biomarkers for liver and kidney functions and adverse birth outcomes Apgar score and gestational age. No significant association was found between heavy metals Hg and lead and adverse birth outcomes.

Development of a Pilot Literacy Scale to Assess Knowledge, Attitudes, and Behaviors towards Climate Change and Infectious Disease Dynamics in Suriname

Prior research has shown that climate literacy is sparse among low- and middle-income countries. Additionally, no standardized questionnaire exists for researchers to measure climate literacy among general populations, particularly with regards to climate change effects on vector-borne diseases (VBDs). We developed a comprehensive literacy scale to assess current knowledge, attitudes, and behaviors towards climate change and VBD dynamics among women enrolled in the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) cohort in Suriname. Items were generated by our research team and reviewed by a group of six external climate and health experts. After the expert review, a total of 31 climate change and 21 infectious disease items were retained. We estimated our sample size at a 10:1 ratio of participants to items for each scale. In total, 301 women were surveyed. We validated our scales through exploratory (n = 180) and confirmatory factor analyses (n = 121). An exploratory factor analysis for our general Climate Change Scale provided a four-construct solution of 11 items. Our chi-squared value (X2 = 74.32; p = 0.136) indicated that four factors were sufficient. A confirmatory factor analysis reinforced our findings, providing a good model fit (X2 = 39.03; p = 0.23; RMSEA = 0.015). Our Infectious Disease Scale gave a four-construct solution of nine items (X2 = 153.86; p = 0.094). A confirmatory factor analysis confirmed these results, with a chi-squared value of 19.16 (p = 0.575) and an RMSEA of 0.00. This research is vitally important for furthering climate and health education, especially with increases in VBDs spread by Aedes mosquitoes in the Caribbean, South America, and parts of the southern United States.

Geographic differences in exposures to metals and essential elements in pregnant women living in Suriname

BACKGROUND

In Suriname, 20% of pregnancies end in adverse birth outcomes. While prenatal exposure to metals may lead to adverse health outcomes, exposure assessments in Suriname are scant. Environmental contamination from mercury (Hg) used in artisanal goldmining in the Amazonian Interior, and the uncontrolled use of pesticides in suburban regions are of particular concern.

OBJECTIVE

This study assessed geographic differences in exposures to metals and essential elements in pregnant Surinamese women.

METHODS

This study is a subset (n = 400) of the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) cohort study. Sector-field inductively-coupled plasma mass spectrometry was used to determine concentrations of lead (Pb), Hg, selenium (Se), cadmium (Cd), manganese (Mn) and tin (Sn) in whole blood of the pregnant women. High vs. low exposures to Pb and Hg were determined and were based respectively on CDC (3.5 ug/dL) and USEPA (3.5 ug/L) action levels. Differences in geographic exposures were tested with the Mann-Whitney U-test, and differences between blood elemental concentrations and action levels for Pb and Hg with the Wilcoxon signed rank test. The association between demographics and high exposures of Pb and Hg was examined with multivariate logistic regression models.

RESULTS

The median concentrations of Pb, Hg and Se (5.08 μg/dL, 7.87 μg/L, and 228.26 μg/L respectively) in Interior women, were higher than the Urban and Suburban regions (p < 0.001), and higher than internationally accepted action levels (p < 0.001). The median concentrations of Mn and Sn found in Suburban women (17.55 and 0.97 ug/L respectively) were higher than Urban and Interior regions (p < 0.02).

SIGNIFICANCE

Pregnant women living in Suriname's Amazonian Interior are exposed to Hg and Pb at levels of public health concern. Urgently needed is a comprehensive source characterization assessment and the development, implementation and monitoring of environmental health policies, specifically addressing the chemicals of concern.

IMPACT

In a subset of participants enrolled in the CCREOH environmental epidemiology cohort study elevated levels of Hg and Pb were identified. This is the first comprehensive exposure assessment in the Surinamese population. Health concerns include adverse birth- and neurodevelopmental outcomes. Geographic differences require a tailored approach to health intervention and comprehensive source characterization. Future research should ascertain the role of Se as a potential protective factor. Environmental policy development, implementation and monitoring is pivotal to mitigate exposures to these neurotoxicants.

The Single and Combined Effects of Prenatal Nonchemical Stressors and Lead Exposure on Neurodevelopmental Outcomes in Toddlers: Results from the CCREOH Environmental Epidemiologic Study in Suriname

The primary aim of this prospective study was to examine the single and combined effect of prenatal exposure to perceived stress, probable depression, and lead on toddlers' neurodevelopment using the Bayley Scales of Infant and Toddler Development, third edition. Data from 363 mother-toddler pairs enrolled in the Caribbean Consortium for Research in Environmental and Occupational Health prospective cohort study were analyzed. A prenatal lead exposure of ≥3.5 µg/dL was associated with significantly lower receptive (p = 0.008) and expressive (p = 0.006) communication scaled scores. Moderate and severe maternal prenatal probable depression scores were associated with significantly lower fine (p = 0.009) and gross (p = 0.009) motor scaled scores. However, a maternal report of prenatal stress was not associated with neurodevelopmental outcomes. After adjusting for maternal demographics, prenatal stress and lead exposure, prenatal probable depression remained predictive of the toddlers' gross motor scaled scores (β -0.13, 95% CI [-0.24--0.02]). Similarly, when adjusting for demographics, prenatal stress and probable depression, prenatal lead exposure remained a significant predictor of their receptive communication scaled scores (β -0.26, 95% CI [-0.49--0.02]). An analysis testing combined exposure to perceived stress, probable depression, and lead exposure, measured using a cumulative risk index, significantly predicted the child fine motor scaled scores after adjusting for other covariates (β -0.74, 95% CI: [-1.41--0.01]).

Linking complex disease and exposure data-insights from an environmental and occupational health study

The disparate measurement protocols used to collect study data are an intrinsic barrier to combining information from environmental health studies. Using standardized measurement protocols and data standards for environmental exposures addresses this gap by improving data collection quality and consistency. To assess the prevalence of environmental exposures in National Institutes of Health (NIH) public data repositories and resources and to assess the commonality of the data elements, we analyzed clinical measures and exposure assays by comparing the Caribbean Consortium for Research in Environmental and Occupational Health study with selected NIH environmental health resources and studies. Our assessment revealed that (1) environmental assessments are widely collected in these resources, (2) biological assessments are less prevalent, and (3) NIH resources can help identify common data for meta-analysis. We highlight resources to help link environmental exposure data across studies to support data sharing. Including NIH data standards in environmental health research facilitates comparing and combining study data, and the use of NIH resources and adoption of standard measures will allow integration of multiple studies and increase the scientific impact of individual studies.

Characterization of Urinary Pesticide Metabolite Concentrations of Pregnant Women in Suriname

Prenatal exposure to pesticides and the association with adverse health outcomes have been examined in several studies. However, the characterization of pesticide exposure among Surinamese women during pregnancy has not been assessed. As part of the Caribbean Consortium of Research in Environmental and Occupational Health research program, 214 urine samples were collected from pregnant women living in three regions in Suriname with different agricultural practices: capital Paramaribo, the rice producing district Nickerie, and the tropical rainforest, the Interior. We used isotope dilution tandem mass spectrometry to quantify urinary concentrations of biomarkers of three pesticide classes, including phenoxy acid herbicides and organophosphate and pyrethroid insecticides, all of which are commonly used in agricultural and residential settings in Suriname. We observed that participants residing in Nickerie had the highest urinary metabolite concentrations of 2,4-dichlorophenoxyacetic acid and pyrethroids compared to those from Paramaribo or the Interior. Paramaribo had the highest concentrations of organophosphate metabolites, specifically dialkyl phosphate metabolites. Para-nitrophenol was detected in samples from Paramaribo and the Interior. Samples from Nickerie had higher median urinary pesticide concentrations of 2,4-dichlorophenoxyacetic acid (1.06 μg/L), and the following metabolites, 3,5,6-trichloro-2-pyridinol (1.26 μg/L), 2-isopropyl-4-methyl-6-hydroxypyrimidine (0.60 μg/L), and 3-phenoxybenzoic acid (1.34 μg/L), possibly due to residential use and heavy rice production.

The Association between Mercury and Lead Exposure and Liver and Kidney Function in Pregnant Surinamese Women Enrolled in the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) Environmental Epidemiologic Cohort Study

Exposure to mercury (Hg) and lead (Pb) may have an effect on pregnant women. We assessed the effect of exposure to mercury and lead on liver and kidney functions in a subcohort of pregnant women who participated in the Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH)—Meki Tamara, study. From 400 women aged 16−46 living in rural, urban, and interior regions of Suriname, we measured blood mercury and blood lead levels. Creatinine, urea, and cystatin C were measured to assess kidney function, and aspartate amino transferase (AST), alanine amino transferase (ALT), and gamma-glutamyl transferase (GGT) were measured to assess liver function. Education, region, and ethnicity showed significant differences for both blood mercury and lead levels, which all had p-values < 0.001. Creatinine and urea were elevated with higher mercury blood levels. Our findings also suggest a relationship between high mercury blood levels and potential harmful effects on liver and kidney function.

Prenatal Exposure to Mercury, Manganese, and Lead and Adverse Birth Outcomes in Suriname: A Population-Based Birth Cohort Study

Globally, adverse birth outcomes are increasingly linked to prenatal exposure to environmental contaminants, such as mercury, manganese, and lead. This study aims to assess an association between prenatal exposure to mercury, manganese, and lead and the occurrence of adverse birth outcomes in 380 pregnant women in Suriname. The numbers of stillbirths, preterm births, low birth weights, and low Apgar scores were determined, as well as blood levels of mercury, manganese, lead, and relevant covariates. Descriptive statistics were calculated using frequency distributions. The associations between mercury, manganese, and lead blood levels, on the one hand, and adverse birth outcomes, on the other hand, were explored using contingency tables, tested with the χ2-test (Fisher's exact test), and expressed with a p value. Multivariate logistic regression models were computed to explore independent associations and expressed as (adjusted) odds ratios (aOR) with 95% confidence intervals (CI). The findings of this study indicate no statistically significant relationship between blood mercury, manganese, or lead levels and stillbirth, preterm birth, low birth weight, and low Apgar score. However, the covariate diabetes mellitus (aOR 5.58, 95% CI (1.38-22.53)) was independently associated with preterm birth and the covariate hypertension (aOR 2.72, 95% CI (1.081-6.86)) with low birth weight. Nevertheless, the observed high proportions of pregnant women with blood levels of mercury, manganese, and lead above the reference levels values of public health concern warrants environmental health research on risk factors for adverse birth outcomes to develop public health policy interventions to protect pregnant Surinamese women and their newborns from potential long-term effects.

Gene-environment interactions related to maternal exposure to environmental and lifestyle-related chemicals during pregnancy and the resulting adverse fetal growth: a review

Background

There are only limited numbers of reviews on the association of maternal-child genetic polymorphisms and environmental and lifestyle-related chemical exposure during pregnancy with adverse fetal growth. Thus, this article aims to review: (1) the effect of associations between the above highlighted factors on adverse fetal growth and (2) recent birth cohort studies regarding environmental health risks.

Methods

Based on a search of the PubMed database through August 2021, 68 epidemiological studies on gene-environment interactions, focusing on the association between environmental and lifestyle-related chemical exposure and adverse fetal growth was identified. Moreover, we also reviewed recent worldwide birth cohort studies regarding environmental health risks.

Results

Thirty studies examined gene-smoking associations with adverse fetal growth. Sixteen maternal genes significantly modified the association between maternal smoking and adverse fetal growth. Two genes significantly related with this association were detected in infants. Moreover, the maternal genes that significantly interacted with maternal smoking during pregnancy were cytochrome P450 1A1 (CYP1A1), X-ray repair cross-complementing protein 3 (XRCC3), interleukin 6 (IL6), interleukin 1 beta (IL1B), human leukocyte antigen (HLA) DQ alpha 1 (HLA-DQA1), HLA DQ beta 1 (HLA-DQB1), and nicotinic acetylcholine receptor. Fetal genes that had significant interactions with maternal smoking during pregnancy were glutathione S-transferase theta 1 (GSTT1) and fat mass and obesity-associated protein (FTO). Thirty-eight studies examined the association between chemical exposures and adverse fetal growth. In 62 of the 68 epidemiological studies (91.2%), a significant association was found with adverse fetal growth. Across the studies, there was a wide variation in the analytical methods used, especially with respect to the genetic polymorphisms of interest, environmental and lifestyle-related chemicals examined, and the study design used to estimate the gene-environment interactions. It was also found that a consistently increasing number of European and worldwide large-scale birth cohort studies on environmental health risks have been conducted since approximately 1996.

Conclusion

There is some evidence to suggest the importance of gene-environment interactions on adverse fetal growth. The current knowledge on gene-environment interactions will help guide future studies on the combined effects of maternal-child genetic polymorphisms and exposure to environmental and lifestyle-related chemicals during pregnancy.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.21-00033.

Sociodemographic Influences on Perceived Stress during Pregnancy: Results from the CCREOH Environmental Epidemiologic Study, Suriname

Screening for prenatal stress is not routine in Suriname, despite its significant impact on maternal and newborn health. This study assessed the prevalence of high perceived prenatal stress and its sociodemographic predictors in three geographic areas in Suriname. In this cross-sectional study, data from 1190 participants of the Caribbean Consortium for Research in Environmental and Occupational Health cohort study were analyzed. Cohen’s Perceived Stress Scale was completed during pregnancy to ascertain high perceived stress (cut-off score 20). The association between maternal sociodemographic factors and high perceived stress was examined using the chi-square test and logistic regression models; 27.5% of all participants had high perceived stress with statistically significant lower rates in Nickerie (18.8%) compared with Paramaribo (29.8%; p = 0.001) and the Interior (28.6%; p = 0.019). Maternal sociodemographic factors moderated the difference between the Interior and Nickerie. Participants from Paramaribo had statistically significant higher odds of high perceived stress compared to those from Nickerie, independent of their age and educational level (adjusted OR = 1.94; 95% confidence interval 1.32–2.86). Perceived stress during pregnancy is predicted by sociodemographic factors. These findings identified target groups for interventions in Suriname. Policy makers should consider integrating perceived stress assessment as a routine part of prenatal care.

Poor Adherence to the WHO Guidelines on Feeding Practices Increases the Risk for Respiratory Infections in Surinamese Preschool Children

Poor feeding practices in infants and young children may lead to malnutrition, which, in turn, is associated with an increased risk of infectious diseases, such as respiratory tract infections (RTIs), a leading cause of under-five mortality. We explored the association between RTIs and the WHO infant and young child feeding (IYCF) indicators: minimum dietary diversity (MDD), minimum meal frequency (MMF), and minimum acceptable diet (MAD), among infants and preschool children in Suriname. A validated pediatric food frequency questionnaire was used and data on RTIs, defined as clinical care for fever with respiratory symptoms, bronchitis, or pneumonia were obtained. Associations between feeding indicators and RTIs were explored using hierarchical logistic regression. Of 763 children aged 10-33 months, 51.7% achieved the MDD, 88.5% the MMF, and 46.5% the MAD. Furthermore, 73% of all children experienced at least one upper and/or lower RTI. Children meeting the MDD and MAD had significantly lower odds on RTIs (OR 0.53; 95%CI: 0.37-0.74, p < 0.001; OR 0.55; 95%CI: 0.39-0.78, p < 0.001, respectively). The covariates parity and household income were independently associated with RTIs. In conclusion, MDD and MAD were associated with (upper) RTIs. Whether these indicators can be used as predictors for increased risk for RTIs should be assessed in future prospective studies.

Validity, reliability, and transcultural adaptations of the Bayley Scales of Infant and Toddler Development (BSID-III-NL) for children in Suriname

BACKGROUND

A valid and reliable measure of infant neurodevelopment is needed in Suriname, South America. The Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III), was created for evaluation of United States infants and toddlers and subsequently validated for use in Dutch speaking infants of the Netherlands (BSID-III-NL). Given that Suriname was a previous Dutch colony and Dutch remains the national language of Suriname, this study sought to evaluate the psychometric properties of the BSID-III-NL in Suriname.

AIMS

Given that the cultural context differs between Suriname, the United States, and the Netherlands, the aims of this study were to determine if any cultural adaptations of the BSID-III-NL were needed for Surinamese infants and to evaluate its psychometric properties.

METHODS

Two hundred and ninety-nine infants between the ages of 10 to 26 months were assessed in three geographic regions of Suriname between May 2018 and July 2019. Minor adaptations to the BSID-III-NL imagery were made based on the input of Surinamese pediatricians and neuropsychologists who were also involved in the administration of the BSID-III-NL in Suriname. Raw scores were collected for the cognitive, communicative, and motor subscales of the BSID-III-NL. Factor structure was evaluated with exploratory factor analysis and cluster analysis, and reliability of internal consistency was assessed using Cronbach's alpha coefficient for each subscale.

RESULTS

Content validity was endorsed by pediatricians and neuropsychologists in Suriname who participated in the administration of the BSID-III-NL. Construct validity was demonstrated through agreement of items from cluster analysis where at least 81.56% of all variability was explained by clustering with correct or incorrect responses and mean raw scores in subscales increased with age group. Cronbach's alpha coefficient was above 0.77 for all subscales.

CONCLUSIONS

This internationally validated developmental measure was found to be valid and reliable in assessing neurodevelopment of infants in Suriname.

The Cumulative Risk of Prenatal Exposures to Chemical and Non-Chemical Stressors on Birth Outcomes in Suriname

The cumulative exposure to chemical and non-chemical stressors may have an impact on birth outcomes. The aim of this study is to examine the cumulative exposure of a mixture of chemicals (mercury, lead, selenium and tin) and non-chemical stressors (social support, perceived stress, probable depression and BMI) on birth outcomes (birthweight, gestational age at birth, and Apgar score at 5 min). The study population is a subset (n = 384) of the Caribbean Consortium for Research in Environmental and Occupational Health–MeKiTamara prospective cohort study. Associations between the latent chemical construct, non-chemical stressors and birth outcomes were assessed using path models. The results showed a significant direct relationship between perceived stress and birthweight (β = −0.17), however even though the relationship between perceived stress and depression was significant in all three path models (β = 0.61), the association between depression and birth outcomes was not significant. Perceived stress was significantly associated with community engagement (β = −0.12) and individual resilience (β = −0.12). BMI (β = 0.12) was also significantly directly associated with birthweight. The latent chemical construct did not show an association with the birth outcomes. Our data indicate the need for the development of a support system for pregnant women by involving them in prenatal care programs to reduce maternal stress, which may also influence depression and (in)directly improve the birth outcomes. Interventions regarding weight management for women of childbearing age are necessary to halt obesity and its negative effects on birth outcomes.

Association of Mercury Exposure and Maternal Sociodemographics on Birth Outcomes of Indigenous and Tribal Women in Suriname

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.

Prenatal exposure to metals and autism spectrum disorder: Current status and future directions

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder with genetic and environmental contributors to etiology. Many metals have the potential to be neurotoxic and their exposures are widespread. The field of metals exposure and ASD research is emerging, and in this review article we assess the current state of the literature, with emphasis on the previous two years. Epidemiology studies are discussed with respect to exposure timing, exposure matrix, and outcome assessment. Toxicology studies are described for exposure dosing and timing, as well as behavioral and molecular outcomes. Further epidemiological and toxicological investigations can identify the timing and importance of metals as ASD risk factors and uncover biological mechanisms for risk mitigation and therapeutic strategies.