Mosquito bites are annoying – they itch, sting and hurt, so naturally many people apply repellent to get a holiday free from itching. But not all mosquito repellents are as safe as they seem. New international research suggests that repellents containing the substance DEET can harm not only mosquitoes but also humans. Because of this reason Danish professor at the Faculty of Pharmacy (Det Farmaceutiske Fakultet) at Copenhagen University, Bent Halling-Sørensen, believes that the substance DEET should undergo further investigation.
In Denmark DEET is not approved in mosquito repellents, but nevertheless many Danes buy effective sprays and lotions containing DEET when travelling to Sweden and Thailand, where the remedies containing DEET are popular.
Experts agree on DEET danger
In the scientific journal BMC Biology, the international research team behind the study informs that DEET works as a poison to the nervous system of both insects and mammals. Laboratory tests on mosquitoes, cockroaches and mice show that DEET inhibits the effect of an enzyme, which is important for the function of the central nervous system in humans.
Head of research, Vincent Corbel of the Institut de Recherche pour le Développement in Montpellier, raises following question: “These findings call into question whether it is safe to use DEET – especially in combination with other chemicals.”
Professor Bent Halling-Sørensen seems to echo Corbel’s theory. The professor believes that since the nervous systems of humans and animals are similar, it is likely that DEET may have the same toxic effect on humans as it has been shown to have on animals and insects – if indeed it can penetrate the cell membranes. “It is not so surprising when you have a fatty substance that can pass through cell barriers and reach through to the nerve paths,” says Bent Halling-Sørensen.
But at the same time he stresses the fact that DEET is present in very small doses and that he himself would rather use products containing DEET than exposing himself to malaria.
According to scientists, 200 million people worldwide use products containing DEET each year. The EU is currently considering whether DEET should be approved for use in mosquito repellents throughout the union.
Five popular mosquito repellents containing DEET: