Chlorine Insecticide parasites pesticide chlorate chlorite ions Hexachlorobenzene

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Chlorine Insecticide

DDT
https://en.m.wikipedia.org/wiki/DDT

Dichlorodiphenyltrichloroethane (DDT) is an organochlorine, originally developed as an insecticide, it became infamous for its environmental impacts.

Organochlorine
https://en.m.wikipedia.org/wiki/Organochloride

organochloride, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine.