Abstract: This article reports the results of the quantitative analysis for the DNA content of cell nucleus of the skin lesion in patients with endemic arsenism by using the technique of flow cytometry,the skin lesions include palmoplantar hyperkeratosis,abnormal pigmentation on trunk and skin cancers.Our results showed that the DNA indices of the different skin lesions of patients in endemic arsenism were significantly higher than those of controls(P<0.01,P<0.05),but there was no significant difference in the DNA index and the cell cycle percentage between the palmoplantar hyperkeratosis and the skin cancer.It is suggested that arsenical keratosis develops easily into skin cancer.It is our opinion that there may be a similarity between the functional activity of epidermal ceils of above two lesions and the information of cell dynamics.

Key words: Arsenism, Flow cytometry, DNA index