Prepn: GB 882111; M. W. Harman, J. J. D'Amico, US 3330823 (1961, 1967 both to Monsanto). Toxicity data: Bailey, White, Residue Rev. 10, 97 (1965). Mutagenicity studies: F. DeLorenzo et al., Cancer Res. 38, 13 (1978); I. Schuphan et al., Science 205, 1013 (1979). Herbicidal activity: R. Grover et al., Weed Res. 19, 363 (1979). GLC determn in milk and plant tissue: L. W. Cook et al., J. Assoc. Off. Anal. Chem. 65, 215 (1982). Review of carcinogenic risk: IARC Monographs 30, 235-244 (1983).