Contamination of Libyan commercial milk obtained from six different sources by some chlorinated pesticides was studied using gas-liquid chromatography with electron-capture detector. The results of this investigation revealed that out of 59 analyzed samples, 40(67.8%) were contaminated by one or more chlorinated
pesticides. Moreover, HCB and lindane were the most prevalent compounds with contamination frequency of about 37 % in both cases. Other organochlorine contaminants were also found at the frequency of 6.8 % for aldrin, 10% for pp' DDE, 5 % for pp:-DDD and 16.9% for pp'-DDT. Except in some cases where the contaminants were only detected in traces, residues of these were often present at concentrations higher than the permitted tolerance residue levels. The public health significance of chlorinated pesticide residues were discussed.