Faculty of Health Sciences
School of Health Systems and Public Health
School of Health Systems and Public Health
Selected Highlights from Research Findings
Although DDT has been banned for international use, countries like South Africa have restricted use for malaria vector control. South Africa is a signatory to the Stockholm Convention on the Control of Persistent Organic Pollutants (POPs), including DDT, and now has the obligation to limit and control the release of substances like DDT into the environment. In response to mounting concerns about the influence of environmental chemicals on human health, a cross-sectional epidemiological study was initiated by Prof Tiaan de Jager and his team to specifically investigate the effects of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) (DDT) on male reproductive health. More than 300 men from Venda, Limpopo, where DDT is still sprayed, participated in the project. Semen analyses, toxicological target analyses and hormone profiles were included. Various sperm parameters were affected and very high concentrations of DDT and metabolites were detected in the blood serum. The effects of DDT on seminal parameters were clear and the project will be extended. DDT was also shown to have an effect on the sperm chromatin and DNA. In addition to the epidemiological approach, reproductive toxicology studies were performed. A general trend in decreased fertility parameters was observed after exposure of rats to a mixture of DDT, deltamethrin, nonylphenol and phytoestrogens. DDT and deltamethrin, at environmentally relevant concentrations, had negative effects on reproductive health, with phytoestrogens in combination with other endocrine disrupting chemicals (including DDT) showing synergistic effects
Contact person: Prof C de Jager.
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