o,p'-DDT is an organochlorine pesticide that induces mortality of malaria mosquito (A. quadrimaculatus) fourth-instar larvae and A. aegypti larvae when used at concentrations ranging from 0.005 to 0.03 and 0.025 to 5 ppm, respectively. It induces 100% mortality of goldfish (C. auratus) at a concentration of 4 ppm. o,p'-DDT is estrogenic, increasing oviduct weight and glycogen content of chicken and Japanese quail. It enhances mammary gland differentiation and increases epithelial cell proliferation in mammary terminal end buds in pubertal female rats. o,p'-DDT is a persistent organic pollutant (POP) and is elevated in the sera of pregnant women in malaria-endemic regions of South Africa. Formulations containing o,p'-DDT have been used to control mosquito populations and prevent the spread of malaria.