The effect of the working environment on occupational skin disease development in workers processing rockwool.

Our examinations involved 259 workers (46 females and 213 males) manufacturing insulation matting of rockwool and phenol-formaldehyde resin. The control group included 529 people. All of the subjects were patch-tested. The age-adjusted relative risk was used as a measure for evaluating the increase in the incidence of dermatitis and allergy to metals. An atomic absorption method was used to determine metal content in rockwool. Dermatitis was found in every fourth subject examined, oil acne in every tenth subject; 7.3% of the subjects examined were found to be allergy-positive to nickel, 6.9% to chromium, 5.0% to cobalt, 3.1% to formaldehyde, 1.5% to phenol-formaldehyde resin, 0% to phenol. Out of the 39 subjects examined twice (in 1988 and 1990), 5 were found to be allergy-positive to nickel during the second examination. A statistically significant increase in the risk of incidence of occupational dermatitis and allergy to nickel and cobalt was found in people producing insulation products made of rockwool. The latter material was found to contain 200 ppm chromium, 88 ppm nickel and 29 ppm cobalt.