Human health effects from DDT at low environmental doses are unknown. Following exposure to high doses, human symptoms can include vomiting, tremors or shakiness, and seizures. Laboratory animal studies showed effects on the liver and reproduction. DDT is considered a possible human carcinogen.

Was Banning DDT a mistake?

Yes, DDT was overused, and there were concerns about the effect on bird eggs. There were also concerns that insects might become resistant. Unfortunately, the outright ban had the consequence of making DDT unavailable, greatly increasing the incidence of Malaria in Africa and other tropical areas.

Was DDT ever considered safe?

It remains one of the most controversial decisions the E.P.A. has ever taken. Ruckelshaus was under a storm of pressure to ban DDT. But Judge Edmund Sweeney, who ran the E.P.A.'s hearings on DDT, concluded that DDT was not hazardous to humans and could be used in ways that did not harm wildlife.