Prehistoric:Sulfur,whale oil,arsenic,nicotine, chrysanthemum,copper Early 19th Century:ethylene bromide,ethylene oxide,carbon disulfide (as fumigants) DDT:Synthesized by Zeideler,1874;Patented Muller,1944(to Geigy) Beginning of World War Il:DDT,dinitrocresol, 2,4-D TEPP:Used as war gas in WW,insecticide in early 1940s,Parathion:Germany 1944  Prehistoric: Sulfur, whale oil, arsenic, nicotine, chrysanthemum, copper  Early 19th Century: ethylene bromide, ethylene oxide, carbon disulfide (as fumigants)  DDT: Synthesized by Zeideler, 1874; Patented Müller, 1944 (to Geigy)  Beginning of World War II: DDT, , dinitrocresol, 2,4-D  TEPP: Used as war gas in WW, insecticide in early 1940s, Parathion: Germany 1944