Serial hair and nail specimens were obtained from 18 patients with rheumatoid arthritis receiving chrysotherapy. Punch biopsies of skin lesions and normal-appearing skin from 4 other patients with gold dermatitis, and serial skin biopsies from 4 additional patients were obtained at intervals during chrysotherapy. Gold content was measured in these samples using neutron activation analysis. Small quantities of gold were found in hair (mean = 0.30 pg/g), nail (mean = 0.17 pg/g), and skin (mean = 0.03 pg/g) prior to chrysotherapy, with two-to fivefold increases after 3-12 months of treatment. Compared to those from patients who did not develop gold toxicity, gold concentrations in all three tissues were similar in patients who developed gold toxicity. Gold levels were identical in skin lesions and normal-appearing skin of patients with gold dermatitis. These findings indicate that gold has little affinity for keratinous tissues, and that determination of gold content in these tissues is not helpful in differentiating gold-toxic from nontoxic patients.Recent studies (1,2) have confirmed earlier reports (3) of the efficacy of gold compounds in the treatment of rheumatoid arthritis (RA). Although gold compounds