PLATINUM SALT SENSITIVITY IN REFINERY WORKERS - INCIDENCE AND EFFECTSOF SMOKING AND EXPOSURE

Objective-To measure the incidence of platinum salt sensitivity (PSS) in refinery workers and examine the influence of cigarette smoking and exposure to platinum salts on sensitisation. Design-A prospective coh ort study with examination of workers at quarterly intervals for 18 mo nths, and again at 24 months. Setting-A South African primary platinum refinery. Subjects-78 new recruits, selected by the refinery's usual procedure, without apparent atopy and in good respiratory health. Resu lts-After 24 months 32 (41%) subjects had been diagnosed PSS and were subsequently medically separated. Twenty two (28%) cases were confirme d by positive skin prick test to platinum salts, 10 (13%) cases were s ymptomatic but skin prick negative. Incidence of cases per 100 person- months was 1.9 skin prick positive and 0.8 negative. Risk of sensitisa tion was about eight times greater for smokers than non-smokers, and s ix times greater for high exposure than low exposure. Conclusion-Smoki ng and intensity of exposure were definitely associated with developme nt of PSS. Positive response to platinum salt skin prick test had a 10 0% positive predictive value for symptoms and signs of PSS if exposure continued.