Contact sensitivity to arsenical compounds. Clinical and experimental studies.

Two arsenic compounds (sodium arsenate and sodium arsenite) were included in our standard patch test series and 2 of 379 tested dermatitis patients reacted. They had not experienced any exposure to arsenicals and showed concomitant reactions to nickel and cobalt. In the guinea pig maximization test (GPMT) the compounds were found to be Grade-I-allergens. There are some convincing case reports in the literature on contact sensitivity to arsenicals and the discrepancy between these reports and the results from the GPMT should be further evaluated by clinical studies on workers with arsenical dermatitis.