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Deet toxicity concerns

BMC Biology, a peer reviewed open access journal specialising in biology and biomedical sciences, has published an article that aimed to investigate the molecular target site for N,N-Diethyl-3-methylbenzamide (deet) and its mechanism of toxicity. The study has been reported in the general media (BBC).

The study found the deet inhibits cholinesterase activity at enzyme level in insects and humans. Toxicological experiments were also conducted in dissections produced from cockroaches and mice. The authors conclude that their findings "question the safety of deet" and they highlight the need for the "development of safer insect repellents".

However, the relevance of these experiments to real world usage of deet has been questioned. Professor Brian Greenwood, from the London School of Hygiene and Tropical Medicine, has advised that "deet has been used for decades with few reported side effects". The risks of contracting insect borne tropical diseases must be weighed against the potential harms of using deet. Patients should be advised to only use deet on exposed areas of skin and it should not be applied to cuts, wounds or irritated skin.

Action: Clinicians should be aware of these safety concerns. Deet remains an effective solution in the prevention of insect bites and the spread of tropical diseases such as malaria.