Food Safety Focus (7th Issue, February 2007) – Food Incident Highlight

DDT Residues and Food Safety

DDT, once a widely-used broad-spectrum pesticide, has been banned in most countries and is regarded as a persistent organic pollutant. Although the use of DDT in agriculture has been stopped for years in Hong Kong, on the Mainland and in many other countries, the residue still persists in the environment and therefore its presence in some plants and animals is still unavoidable. In recent years, local food samples detected with DDT were found at low levels and did not provide evidence of illegal use.

The Centre for Food Safety conducted a study on dietary exposure to DDT of local secondary school students in 2006. The results suggest that the exposure levels, including high consumers, are well within the safety reference value of 10 microgram / kg body weight / day set by the Joint Food and Agriculture Organization / World Health Organization Meeting on Pesticide Residues. The results of total diet studies on the Mainland indicate that DDT exposure from food has been on the decline since 1990s, which was more consistent with environmental persistence of DDT than with continuous agricultural use.