Abstract:
Most evidence about the health consequences of pesticide exposures comes from occupational settings in high-income countries. However, larger populations can be exposed through agricultural drift, especially in low- and middle-income countries (LMIC). Despite the growing and widespread use of pesticides, there is scarcity of studies assessing the national level effect of environmental exposures to pesticides. Ecuador has one of the highest application rates as the country is highly dependent on its export-bound agricultural industry. We applied spatial analyses to explore the distribution of low birth weight (LBW) in Ecuador and its association with pesticide exposures for 2015 and 2016. We used a gridded global database of pesticide use estimates, PEST-CHEMGRIDSv1, and public records of ∼500,000 births. First, we applied spatial cluster analysis to assess the spatial distribution of LBW and identify areas of elevated risk. Then, we used a Bayesian spatial regression to evaluate the effect of application rates on LBW at the parish level (n = 1030). In addition, we used nested models to assess to what extent the covariates account for the spatial effect. Elevated risks of LBW were observed in the central Coast and Inter-Andean regions. Moreover, we found evidence that living in areas with high levels of pesticide use may be associated with increased odds of LBW (OR: 1.10, 95% CI: 1.01 – 1.20). The spatial variability of this association was partially accounted by environmental factors known to affect pesticide drift, such as wind speed, solar radiation, and temperature. Given the limited national-level studies on pesticide exposures globally, geospatial modelling offers valuable tools to estimate the burden of pesticide exposures and identify regions that may require further detailed assessments. This information is central to evaluate intensive export-led agriculture development projects and provide evidence for regulations around pesticide use in LMIC.
Citation:
Federico Andrade-Rivas, Jerry Spiegel, Jorge Andrés Delgado-Ron, Matilda van den Bosch, Lael Parrott, Sarah B. Henderson, Agricultural pesticide exposures in Ecuador and their spatial association with low birth weight: a combined cluster detection and Bayesian modelling approach, Environmental Pollution,Volume 398, 2026,128090, ISSN 0269-7491, https://doi.org/10.1016/j.envpol.2026.128090.