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

Abstract

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/m ², 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.

Keywords

organophosphate pesticides / anthropometric outcomes / children / non-agricultural settings / informal settlements

Informed Consent Statement

Informed consent was obtained from parents or legal guardians, and informed assent obtained from the participating children prior to the commencement of any study procedures.

Data Availability Statement

The raw data of this study is available upon request.

Acknowledgments

This manuscript is part of the Master of Public Health dissertation of H.W. at the University of Cape Town. We thank Jennifer Yen for her bioinformatics input. We also acknowledge the NOVA institute, the holder of the tender with DEA&DP under which the study falls, for managing the tender and assisting in coordinating the fieldwork on this project. Our appreciation of the Project Steering Committee (Ref: EADP/7/2013), particularly Joy Learner, Bhawoodien Parker, Gottlieb Arendse, and Sally Benson from DEA&DP, during project management, and our research nurses, including the local fieldworkers for their commitment and diligence through the fieldwork is hereby acknowledged. Finally, this study would not have been possible without the involvement of the learners, parents, caregivers, teachers, principals, and the School Governing Bodies in providing their time and support during the data collection across the study periods.

Conflicts of Interest

The authors declare no conflict of interest. DEA&DP (Western Cape governmental department), the major funder, project managed the parent study on air pollution and asthma from which data was used for this sub-study. Given the role as the Editorial Board Member, Mohamed Aqiel Dalvie had no involvement in the peer review of this paper and had no access to information regarding its peer-review process. Full responsibility for the editorial process of this paper was delegated to another editor of the journal.

Use of AI and AI-Assisted Technologies

No AI tools were utilized for this paper.

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