. . . . . "1980-12-31" . "Agency for Toxic Substances and Disease Registry" . "U.S. Agency for Toxic Substances and Disease Registry" . "1983-04-19" . "Agency for Toxic Substances and Disease Registry" . . . . . "7.8E7" . . . . . "1985-06-11" . "ATSDR" . . . . . . "1980" . . . "1983" . . . "228" . . . . . "1985" . .