Worm study raises concern about DEET’s effect on reproduction

The findings come from a study in C. elegans — worms that don’t look like they have much in common with humans yet serve as surprisingly useful bellwethers of how toxins in the environment affect human reproduction.

The research, published Jan. 4 in iScience, raises difficult questions. Chief among them is how to balance the possible reproductive harms of DEET-containing products in people — including infertility, miscarriage, or birth defects — with the need to ensure that people remain protected from diseases transmitted through insect bites, such as malaria, Lyme disease, West Nile virus, and Zika virus disease.

Whether and how much DEET use causes reproductive problems in humans will need to be confirmed in future studies. Such studies have been scarce to date in humans because of the ethical concerns involved.

Harvard Medicine News spoke with study senior author Monica Colaiácovo, professor of genetics in the Blavatnik Institute at Harvard Medical School, about what her team found and what it means.