Residential proximity to pesticide applications in Argentine Patagonia: impact on pregnancy and newborn parameters

Pesticide exposure and spontaneous abortion risk: A comprehensive systematic review and meta-analysis

BACKGROUNDS AND AIM

Exposure to pesticides has been proposed as a potential contributor to adverse pregnancy outcomes, possibly through the induction of inflammation, oxidative stress, and disruption of endocrine functions. Nevertheless, the definitive link between prenatal pesticide exposure and the risk of Spontaneous Abortion (SAB) remains uncertain. The objective of this systematic review is to explore and analyze the existing evidence regarding the link between pesticide exposure and the risk of SAB.

METHODS

A comprehensive systematic literature search was carried out on PubMed, Web of Science, and Scopus from their inception until February 2024 to identify relevant studies exploring the potential link between pesticide exposure and SAB. The frequency of SAB events and the total number of patients in each group were used to calculate the Relative Risk (RR) using the Mantel-Haenszel random-effects model. Heterogeneity among the studies was evaluated by visually inspecting the forest plot and performing the Chi-square test and I2 tests. We also used RevMan version 5.4 for Windows for the analysis. We also used the NIH tool to assess the quality of the included studies.

RESULTS

The initial database search yielded 2121 results, with 1525 articles remaining after removing duplicates. After screening, 29 articles were eligible for full-text review, and 18 studies (Four case-control, eleven cohorts, three cross-sectional) were included in the meta-analysis, comprising 439,097 participants. All included studies evaluated the primary outcome, SAB. Most of the included studies were cross-sectional in design, and pesticide exposure was primarily assessed through questionnaires administered to patients. We found that most of our observational studies, precisely 12 out of the total, were deemed fair quality. Four studies were rated poor quality, while only two received a good quality rating. The analysis demonstrated a significant 41 % increase in SAB risk among pregnant women exposed to pesticides compared to pregnant women without exposure to pesticides (RR= 1.41, 95 % CI; [1.10, 1.80], P= 0.006).

CONCLUSION

Our systematic review and meta-analysis revealed a significant 41 % increase in the risk of SAB among pregnant women exposed to pesticides. However, it is essential to acknowledge the limitations of the current evidence: potential publication bias and the inability to establish causality. Moving forward, future research should focus on longitudinal studies, mechanistic insights, and risk reduction strategies. In summary, our findings underscore the urgency of public health measures to protect maternal and fetal health in pesticide-exposed areas. Rigorous research and preventive strategies are crucial to mitigate adverse outcomes.

Long-lasting developmental effects in rat offspring after maternal exposure to acetamiprid in the drinking water during gestation

Neonicotinoids (NNTs) are a class of insecticides proposed to be safe for pest control in urban, suburban, and agricultural applications. However, little is known about their developmental effects after repeated low-dose exposures during gestation. Here, we tested a dose considered subthreshold for maternal toxicity in rats (6 mg/kg/day) by assessing several morphological, biochemical, and neurobehavioral features in preterm fetuses and developing pups after maternal administration of the NTT acetamiprid (ACP) dissolved in the drinking water during gestational days (GD) 2-19. The exploratory evaluation included monitoring maternal body weight gain, fetal viability, body weight and sex ratio, cephalic length, neonatal body weight and sex ratio, metabolic enzymes in the placenta, maternal blood and fetal liver, and anogenital distance and surface righting response during infancy. We also used the circling training test to study the integrity of the associative-spatial-motor response in adolescence. Results showed no consistent findings indicating maternal, reproductive or developmental toxicity. However, we found ACP effects on maternal body weight gain, placental butyrylcholinesterase activity, and neurobehavioral responses, suggestive of a mild toxic action. Thus, our study showed a trend for developmental susceptibility at a dose so far considered subtoxic. Although the ACP concentration in environmental samples of surface water and groundwater has been mostly reported to be much lower than that used in our study, our results suggest that the ACP point of departure used in current guidelines aimed to prevent developmental effects may need to be verified by complementary sensitive multiple-endpoint testing in the offspring.

Pesticides exposure in pregnant Argentinian women: Potential relations with the residence areas and the anthropometric neonate parameters

Intrauterine environment is the first chemical exposure scenario in life, through transplacental transfer. In this study, the aim was to determine concentrations of organochlorine pesticides (OCPs) and selected current use pesticides in the placentas of pregnant women from Argentina. Socio-demographic information, the mother's lifestyle and neonatal characteristics were also analysed and related to pesticides residue concentrations. Thus, 85 placentas were collected at birth, from an area of intensive fruit production for the international market, in Patagonia Argentina. Concentrations of 23 pesticides including, trifluralin (herbicide), the fungicides chlorothalonil and HCB, and the insecticides chlorpyrifos, HCHs, endosulfans, DDTs, chlordanes, heptachlors, drins and metoxichlor, were determined by GC-ECD and GC-MS. Results were first analysed all together and then grouped by their residential settings, in urban and rural groups. Total mean pesticide concentration was 582.6 ± 1034.4 ng/g lw, where DDTs (325.9 ± 950.3 ng/g lw) and chlorpyrifos (188.4 ± 365.4 ng/g lw) showed a high contribution. Pesticide levels found exceeded those reported in low, middle and high income countries from Europe, Asia and Africa. In general, pesticides concentrations were not associated with neonatal anthropometric parameters. When the results were analysed by residence place, significantly higher concentrations of total pesticides and chlorpyrifos (Mann Whitney test p = 0.0003 and p = 0.032, respectively) were observed in placentas collected from mothers living in rural settings compared to urban areas. Rural pregnant women presented the highest pesticide burden (5.9 μg), where DDTs and chlorpyrifos were the major constituents. These results suggested that all pregnant women are highly exposed to complex pesticide mixtures, including banned OCPs and the widely used chlorpyrifos. Based on the pesticide concentrations found, our results warn of possible health impacts from prenatal exposure through transplacental transfer. This is one of the first reports of both chlorpyrifos and chlorothalonil concentrations in placental tissue, and contributes to the knowledge of current pesticide exposure in Argentina.

Associations between residential proximity to agricultural land use as pesticides exposure and birth outcomes

Pesticides are widely used globally. Due to their widespread use, exposure to pesticides is of concern. In addition to occupational exposure, residential exposure during pesticide application is a concern for those living in or near agricultural areas. The objective of this study was to analyze the association between residential proximity to agricultural pesticide use and birth outcomes. The association between residential proximity to agricultural land use as pesticide exposure and birth outcomes was explored in a birth cohort including 283 pregnant women from a medical center in Hualien during 2013-2016. In the third trimester, we collected demographic information and the residential addresses of pregnant women via structured questionnaires. After delivery, newborn birth weight, gestational age, and head circumference were collected from medical records. Maternal residential address during pregnancy was collected for geospatial mapping. The percentages of farmland area within circular buffers of different sizes were applied to estimate pesticide exposure. Associations between residential proximity to agricultural land use as pesticide exposure and birth outcomes were analyzed by multiple linear regression analyses. A significantly smaller head circumference was associated with agricultural farmland located within 400 m (β =  - 0.51 [95% CI, - 0.99, - 0.03], P = 0.037) and 500 m (β =  - 0.67 [95% CI, - 1.14, - 0.19], P = 0.006) radii of residences in the tertile 2 group. A significantly smaller head circumference was also associated with dry farming area within 400 m (β =  - 0.70 [95% CI, - 1.17, - 0.24], P = 0.003) and 500 m (β =  - 0.81 [95% CI, - 1.27, - 0.34], P = 0.001) radii of residences in the tertile 2 group. The multivariate linear regression analyses did not show any significant association between residential farmland area and birth weight or gestational age. In conclusion, residential proximity to agricultural land use as pesticide exposure was associated with negative infant birth outcomes, especially a small head circumference. In the future, agricultural land use information could be combined with biological samples to more accurately assess exposure in pregnant women.

Pesticide exposure and child growth in low- and middle-income countries: A systematic review

BACKGROUND

In low- and middle-income countries (LMICs), pesticides are widely used in agricultural and residential settings. Little is known about how pesticides affect child growth.

OBJECTIVES

To systematically review and synthesise the evidence on the associations between pesticide exposure and adverse birth outcomes and/or impaired postnatal growth in children up to 5 years of age in LMICs.

METHODS

We searched 10 databases from inception through November 2021. We included cohort and cross-sectional studies investigating associations between self-reported or measured prenatal or postnatal pesticide exposure and child growth (postnatal child linear/ponderal growth, and/or birth outcomes). Two researchers screened studies, extracted data, and assessed certainty using GRADE. The protocol was preregistered with PROSPERO (CRD42021292919).

RESULTS

Of 939 records retrieved, 31 studies met inclusion criteria (11 cohort, 20 cross-sectional). All studies assessed prenatal exposure. Twenty-four studies reported on birth weight. Four found positive associations with organochlorines (0.01-0.25 standardised mean difference (SMD)) and two found negative associations (-0.009 SMD to -55 g). Negative associations with organophosphates (-170 g, n = 1) and pyrethroids (-97 to -233 g, n = 2) were also documented. Two (out of 15) studies reporting on birth length found positive associations with organochlorines (0.21-0.25 SMD) and one found negative associations (-0.25 to -0.32 SMD). Organophosphate exposure was negatively associated with birth length (-0.37 cm, n = 1). Organophosphate exposure was also associated with higher risk/prevalence of low birth weight (2 out of nine studies) and preterm birth (2 out of six studies). Certainty of the evidence was "very low" for all outcomes.

CONCLUSION

The limited literature from LMICs shows inconclusive associations between prenatal pesticide exposure, child growth, and birth outcomes. Studies with accurate quantitative data on exposure to commonly used pesticides in LMICs using consistent methodologies in comparable populations are needed to better understand how pesticides influence child growth.

Health Effects of Pesticide Exposure in Latin American and the Caribbean Populations: A Scoping Review

BACKGROUND

Multiple epidemiological studies have shown that exposure to pesticides is associated with adverse health outcomes. However, the literature on pesticide-related health effects in the Latin American and the Caribbean (LAC) region, an area of intensive agricultural and residential pesticide use, is sparse. We conducted a scoping review to describe the current state of research on the health effects of pesticide exposure in LAC populations with the goal of identifying knowledge gaps and research capacity building needs.

METHODS

We searched PubMed and SciELO for epidemiological studies on pesticide exposure and human health in LAC populations published between January 2007 and December 2021. We identified 233 publications from 16 countries that met our inclusion criteria and grouped them by health outcome (genotoxicity, neurobehavioral outcomes, placental outcomes and teratogenicity, cancer, thyroid function, reproductive outcomes, birth outcomes and child growth, and others).

RESULTS

Most published studies were conducted in Brazil (37%, n = 88 ) and Mexico (20%, n = 46 ), were cross-sectional in design (72%, n = 167 ), and focused on farmworkers (45%, n = 105 ) or children (21%, n = 48 ). The most frequently studied health effects included genotoxicity (24%, n = 62 ) and neurobehavioral outcomes (21%, n = 54 ), and organophosphate (OP) pesticides were the most frequently examined (26%, n = 81 ). Forty-seven percent (n = 112 ) of the studies relied only on indirect pesticide exposure assessment methods. Exposure to OP pesticides, carbamates, or to multiple pesticide classes was consistently associated with markers of genotoxicity and adverse neurobehavioral outcomes, particularly among children and farmworkers.

DISCUSSION

Our scoping review provides some evidence that exposure to pesticides may adversely impact the health of LAC populations, but methodological limitations and inconsistencies undermine the strength of the conclusions. It is critical to increase capacity building, integrate research initiatives, and conduct more rigorous epidemiological studies in the region to address these limitations, better inform public health surveillance systems, and maximize the impact of research on public policies. https://doi.org/10.1289/EHP9934.

The Changing Climate and Pregnancy Health

PURPOSE OF REVIEW

Climate change is the biggest public health threat of the twenty-first century but its impact on the perinatal period has only recently received attention. This review summarizes recent literature regarding the impacts of climate change and related environmental disasters on pregnancy health and provides recommendations to inform future adaptation and mitigation efforts.

RECENT FINDINGS

Accumulating evidence suggests that the changing climate affects pregnancy health directly via discrete environmental disasters (i.e., wildfire, extreme heat, hurricane, flood, and drought), and indirectly through changes in the natural and social environment. Although studies vary greatly in design, analytic methods, and assessment strategies, they generally converge to suggest that climate-related disasters are associated with increased risk of gestational complication, pregnancy loss, restricted fetal growth, low birthweight, preterm birth, and selected delivery/newborn complications. Window(s) of exposure with the highest sensitivity are not clear, but both acute and chronic exposures appear important. Furthermore, socioeconomically disadvantaged populations may be more vulnerable. Policy, clinical, and research strategies for adaptation and mitigation should be continued, strengthened, and expanded with cross-disciplinary efforts. Top priorities should include (a) reinforcing and expanding policies to further reduce emission, (b) increasing awareness and education resources for healthcare providers and the public, (c) facilitating access to quality population-based data in low-resource areas, and (d) research efforts to better understand mechanisms of effects, identify susceptible populations and windows of exposure, explore interactive impacts of multiple exposures, and develop novel methods to better quantify pregnancy health impacts.

Spatial variation and association between maternal chemical fertilizer exposure and preterm birth in a rural area in Northern China

Whether maternal macro-environmental chemical fertilizer exposure has an association with the risk of preterm birth remains unclear. This study aimed to investigate the association between maternal exposure to chemical fertilizer during pregnancy and the risk of preterm birth. A total of 13,861 births, including 402 preterm birth from 313 villages in Pingding County, Shanxi Province, China, were analyzed to explore spatial variations of preterm birth risks at the village level. Spatial variations of preterm birth were visualized and tested with Disease Mapping, Moran's I and G* Statistic. The spatial zero-inflated negative binomial model was used to evaluate the incidence rate ratio (IRR) of preterm birth in different chemical fertilizer consumption levels at the village level. A population-based case-control study was conducted including 153 preterm births cases and 204 controls at the household level. The two-level logistic regression model was performed to estimate the association between risks of preterm birth and maternal exposure to chemical fertilizer after adjusting confounding factors. The findings indicated a remarkably clustering effect in relative risks of preterm birth and identified a high-risk clustering region of preterm birth from the south-central to the southwest and a low-risk clustering region in the northern Pingding county. The results of the spatial zero-inflated negative binomial model showed that the risk of preterm birth in the villages with chemical fertilizer consumption≥100 tons was 2.82 (95% CI: 1.50-5.57) times higher than those with <50 tons. Maternal exposure to chemical fertilizer ≥100 tons at village level was associated with an increased risk of preterm birth (aOR 2.14, 95%CI: 1.18-3.96), compared with exposure <50 tons after adjusting for confounding variables. The findings suggests that chemical fertilizers deserve more attention as a potential risk factor of preterm birth.