Preliminary study of the occurrence and distribution of DDT residues in the Jordan watershed, 1971.

Data obtained from the Jordan watershed in 1971 revealed the presence of DDT and its metabolites at various levels along the food chain. Detectable levels of sigmaDDT in water of the Jordan River and two fish ponds ranged from 0.019 to 0.500 ppb, which is 1/10 to 1/500 the maximum level permitted in water by the U.S. Government. Mean residue in phytoplankton was 0.906 mug/g; in zooplankton the mean was 6.49 mug/g. SigmaDDT residue in fish of the Jordan watershed averaged 0.37 mg/kg in carp, 2.59 mg/kg in benith, and 3.34 mg/kg in sardines.