The Relationship between Organophosphate Pesticide Exposure and Anthropometric Outcomes among a Cohort of Children from Four Informal Settlements in the Western Cape

There is limited data on the association between pesticide exposure in children and anthropometric outcomes, particularly in non-agricultural communities and developing countries. This study investigated the association between organophosphate pesticide (OPP) exposure and anthropometric outcomes in primary schoolchildren from four informal settlements in Western Cape Province in South Africa. Using a repeated cross-sectional design of 600 schoolchildren over a 12-month period, urinary dialkyl phosphate (DAP) metabolites, diethylphosphate (DEP), dimethylphosphate (DMP), and dimethylthiophosphate (DMTP) were measured at baseline with DEP and DMP measured at follow-up. Anthropometric measurements height, weight, and Body Mass Index (BMI) were collected at both time points. The mean age for all participants at baseline was 9.93 ± 0.90 years and mean ΣDAP at baseline was 41.78 ± 33.80 ng/mL. Mean changes in weight, height, and BMI from baseline to follow-up for all participants were 6.04 ± 5.29 kg, 6.83 ± 4.00 cm, and 1.05 ± 2.01 kg/m2, respectively. Eighty percent of participants measured below the 50th percentile in height-for-age at baseline, and 76.8% at follow-up. No consistent associations were found between DAPs and anthropometric outcomes. Urinary OPP metabolite measurements and the prevalence of short stature among children in the study were high compared to other settings. The study did not find evidence of an association between OPP exposure and child anthropometric outcomes. Large longitudinal studies with follow-up periods exceeding two years and incorporating pesticide biomonitoring at multiple time-points are recommended.