In order to understand epidemiologic characteristics of dioxins related health impacts, 107 diox in-related, literatures published up to May, 1993 were thoroughly reviewed.
The results obtained are as follows:
1. Review studies on dioxins can be classified into two types : one is studies concentrated on one specific subject related to dioxins such as the effects on skin, birth outcomes, metabolic machanisms in the human body, major sources of expo-sure to the general population, immunotoxicity, association between dioxins and cancers, and research methods on effects of dioxins. The other is review studies dealing with overall aspects of dioxins, among which the report published by Academy of Science of United Stateds of Americain 1993 is the most recent one.
2. Judging by consistency of results and biological plausibility, there were three groups of diseases ; diseases having causal relationship, having possibilities of causal relationship, and having no causal relationship for the time being.
1) The diseases showing causal relationship were lung cancer, Hodgkin ´disease, non-Hodgkin ´lymphoma, soft tissue sarcoma, chlordane, and polyneuropathy
2) the diseases showing possibilities of causal relationship were stomach cancer, lymphatic and haematopoietic cancer, multiple myeloma, skin cancer, diseases of digestive system, and CNS deformity among children born to the people exposed.
3) The diseases showing no causal relationship were oral and laryngeal cancer, esophageal cancer, prostate cancer, kidney cancer, bladder cancer, brain and CNS cancer, diseases of circulatory and respiratory systems.
There were numerous diseases of digestive system, which showed difficulty in establishing definite causal relationship owing to the lack of consistency among researchers.
3. Even though papers dealt with dioxin related mortality and morbidity studies showed high mor tality rate from accident, biological plausibility explaining causal relationship between them should be sought further.
4. There was a high prevalence of hearing loss among Vietnam veterans, and it seemed rather related to the explosive noise in combat than dioxin itself.
5. The current TCDD levels of Vietnam veterans were almost the same as those of the general population.
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