[Show abstract][Hide abstract] ABSTRACT: Identification and quantification of carotenoids in the epidermis of nine patients of chronic arsenic poisoning were done using isocratic reverse phase high performance liquid chromatography (HPLC). The major carotenoids in all the skin biopsies were all-E lutein and 3'-epilutein. Small amount of 2',3'-anhydrolutein, all-E zeaxanthin, and 13-Z zeaxanthin were also present in some of the biopsy samples. Alpha-carotene, beta-carotene, and lycopene were not detected in any sample. The mean (+/- SD) concentration of all-E lutein in the epidermis of healthy volunteers was 1.09 +/- 0.26 microgram/g of wet tissue, whereas it was only 0.29 +/- 0.10 microgram/g in the diffuse dark brown spots of chronic arsenic poisoning. In raindrop-shaped discoloration spots of skin the mean concentration of all-E lutein was 0.86 +/- 0.29 microgram/g of wet tissue. The difference between the concentrations of all-E lutein in the epidermis of healthy volunteers versus patients was for the diffuse dark brown spots statistically significantly (p < 0.05) lower, while this was not significant for the raindrop-shaped discoloration spots. This study suggests that arsenic exposure reduces the number, as well as concentrations of, carotenoids in skin.