Abstract
BACKGROUND: Children in agricultural areas are exposed to organophosphate (OP) and pyrethroid (PYR) insecticides. This explorative study investigated child exposure to OPs and PYRs, comparing temporal and spatial exposure variability within and among urine, wristbands, and dust samples.
METHODS: During spraying season 2018, 38 South African children in two agricultural areas (Grabouw/Hex River Valley) and settings (farm/village) participated in a seven-day study. Child urine and household dust samples were collected on days 1 and 7. Children and their guardians were wearing silicone wristbands for seven days. Intraclass correlation coefficients (ICCs) evaluated temporal agreements between repeated urine and dust samples, Spearman rank correlations (Rs) evaluated the correlations among matrices, and linear mixed-effect models investigated spatial exposure predictors. A risk assessment was performed using reverse dosimetry.
RESULTS: Eighteen OPs/PYRs were targeted in urine, wristbands, and dust. Levels of chlorpyrifos in dust (ICC = 0.92) and diethylphosphate biomarker in urine (ICC = 0.42) showed strong and moderate temporal agreement between day 1 and day 7, respectively. Weak agreements were observed for all others. There was mostly a weak correlation among the three matrices (Rs = -0.12 to 0.35), except for chlorpyrifos in dust and its biomarker 3,5,6-trichloro-2-pyridinol in urine (Rs = 0.44). No differences in exposure levels between living locations were observed. However, 21% of the urine biomarker levels exceeded the health-risk threshold for OP exposure.
CONCLUSIONS: Observed high short-term variability in exposure levels during spraying season highlights the need for repeated sampling. The weak correlation between the exposure matrices points to different environmental and behavioral exposure pathways. Exceeding risk thresholds for OP should be further investigated.
| Original language | English |
|---|---|
| Article number | e282 |
| Number of pages | 14 |
| Journal | Environmental Epidemiology |
| Volume | 8 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Feb 2024 |
Bibliographical note
Publisher Copyright:© 2024 Wolters Kluwer Health. All rights reserved.
Funding
This project is imbedded within the South African-Swiss Bilateral SARChI Chair in Global Environmental Health and supported by the South Africa National Research Foundation (NRF; grant number: 94883), the Swiss State Secretariat for Education, Research and Innovation (SERI), the University of Basel and the Swiss TPH. S.F.’s effort was supported by a fellowship of the Swiss National Science Foundation (SNSF; grant number: P4P4PM_199228,P400PM_180757 and TMSGI3_211325). The authors thank the Research Infrastructure RECETOX (No LM2023069) and project CETOCOEN EXCELLENCE (No CZ.02.1.01/0.0/0.0/17_043/0009632) financed by the Czech Ministry of Education, Youth and Sports for supportive background. This project was supported by the European Union’s Horizon 2020 research and innovation program under grant agreement No 857560. This publication reflects only the author’s view, and the European Commission is not responsible for any use that may be made of the information it contains.
| Funders | Funder number |
|---|---|
| South Africa National Research Foundation | |
| Swiss TPH | |
| Universität Basel | |
| Horizon 2020 Framework Programme | 857560 |
| Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung | TMSGI3_211325, P4P4PM_199228, LM2023069, P400PM_180757, CZ.02.1.01/0.0/0.0/17_043/0009632 |
| Ministerstvo Školství, Mládeže a Tělovýchovy | |
| National Research Foundation of Korea | 94883 |
| Staatssekretariat für Bildung, Forschung und Innovation |
Keywords
- Biomonitoring
- Child exposure
- Endocrine disruptors
- Pesticide
- Vulnerable populations
