Studies on hexachlorocyclohexane and DDT contents in human cerumen and their relationships to cancer mortality.

Organochlorine pesticides in cerumen were used as a biological marker to monitor the exposure of organochlorine pesticides in the human body. The amount of sample used was about 10 mg. The order of magnitude of HCH (hexachlorocyclohexane) isomer content in cerumen was beta greater than alpha greater than gamma greater than delta; for DDT, the order was p,p'-DDE greater than p,p'-DDT. There was little o,p'-DDT and p,p'-DDD. The contents of beta-HCH and p,p'-DDE in cerumen were highly significantly correlated with those in adipose tissue of the same individuals. Approximately 3800 cerumen samples collected from 35- to 54-year-old healthy adults in the general populations of 35 counties were analyzed for HCH and DDT. The accumulation levels of beta-HCH had a geographical character with obvious gradient differences, and the levels were higher in males than in females. The accumulation levels of beta-HCH in the populations studied were highly significantly correlated with the mortality rates from liver cancer, colon/rectum cancer, and lung cancer in males as well as colon/rectum cancer in females (P less than 0.01), suggesting that the effect of HCH on the above cancers should be studied further.