Description
BackgroundSouth Africa is the leading pesticide user in Sub-Saharan Africa and more than 700 active ingredients are registered for agricultural use. However, little is known about the seasonal variations of pesticides in the environment.
Aim
We aimed (i) to measure the seasonal variations of different pesticides in water and ambient air; (ii) to assess the relationship between the measured pesticides with spraying records; and (iii) to characterize environmental and human exposure to cocktails of pesticides.
Methods
The study was conducted in the Western Cape, South Africa between June 2017 and July 2018. We deployed 36 passive water samples in three rivers (styrenedivinylbenzene disks) and 18 passive air samples at six locations (polyurethane foam disks). Water and air samples were analyzed for 254 and 78 active ingredients, respectively. Spraying records were collected from 48 farms.
Results
55 and 16 active ingredients were detected in water and air samples, respectively. The highest levels of active ingredients were observed during the main spraying season. Good correlation between the spraying records and the presence in the water of eleven active ingredients was observed. Out of the measured active ingredients 16 are possibly endocrine disrupting (e.g., thiacloprid and carbendazim) and eight possibly neurotoxic (e.g., chlorpyriphos and diazinon).
Conclusion
The results suggest that several active ingredients persist in the ambient air and enter surface water, leading to potential environmental and human health risks. The possible health effects linked to cumulative exposure to the detected pesticides will be subject to a future health risk assessment in resident populations.
| Period | 7 Aug 2019 |
|---|---|
| Event title | 31st annual conference of the International Society for Environmental Epidemiology (ISEE 2019) |
| Event type | Conference |
| Degree of Recognition | International |