Dichlorodiphenyldichloroethane (DDD) is an organochlorine insecticide that is slightly irritating to the skin.

A further basis is that DDD is similar to and is a metabolite of DDT, another probable human carcinogen.

[2] DDD is no longer registered for agricultural use in the United States, but the general population continues to be exposed to it due to its long persistence time.

[5] 1946 is the date of the earliest recorded use in English of the abbreviation “DDD” to stand for dichlorodiphenyldichloroethane, as far as could be determined.

[3] If one of the p-chlorines in DDD is switched to ortho-position, the result is the chemotherapeutic agent mitotane.