From a total of 993 previously reported cases of occupational skin disease (OSD), 954 (96%) were contacted and 711 (75%) examined. The review time (i.e., period from original diagnosis of OSD until review) varied from a minimum of 6 months to a maximum of over 8 years. Over 60% of cases were reviewed more than 2 years after the original diagnosis was made. More than 50% were still suffering from OSD or consequences related thereto. Clearance was less likely in those who remained in their original, or similar, occupational environment. However, of those who changed their job due to OSD, many suffered aggravation of the dermatitis from factors in the new work environment. Over 10% of cases had evolved into a persistent postoccupational dermatitis without obvious cause. This condition is responsible for considerable impairment and is of medicolegal importance due to confusion as to its relationship to the original occupational factors.

To elucidate further the natural history and prognosis of occupational chromate dermatitis, 120 affected patients, diagnosed between 1980 and 1989, were reviewed. The incidence of chromate dermatitis in Western Australia appeared to remain unchanged over the decade. 65% of patients were construction workers with cement-induced chromate dermatitis. Workers at greatest risk of sensitization were those mixing bagged cement at the work site. The median age at onset of symptoms was 34 years, with 48% having been exposed to chromate for 5 years or less. Only 37% presented to the dermatologist within 12 months of developing symptoms. 76% of patients had ongoing dermatitis at the time of review. Although 48% of the study population had completely changed their occupation to avoid chromate exposure, symptoms persisted in 69%. A delayed diagnosis of chromate sensitivity was noted to be a predictor of chronicity. In view of the potential chronicity of chromate dermatitis and its associated social and occupational impairment, we recommend the addition of ferrous sulphate while mixing bagged cement at the work site. This simple technique targets the workers at greatest risk of becoming sensitized.

993 cases of occupational skin disease (OSD) were diagnosed in a private dermatology practice over an 8-year period. Dermatologists were the major source of referral. The sex ratio was 2.4 males to 1 female. Patch tests were conducted in 79% of cases. Wet work industries predominated in females; in males the causative industries were more varied. Apprentices were affected in a high proportion of hairdressers and food handlers. Atopics accounted for 75% of the apprentice hairdressers. Atopics also were more prevalent in females with OSD than males. 29% of all cases had suffered from OSD for over 2 years before diagnosis. 75% of patients with OSD were less than 40 years of age at onset of OSD. Irritant contact dermatitis predominated over allergic contact dermatitis in all age groups except those over 60 years of age. Nickel was the predominant occupational allergen in females, whereas chromate was the predominant occupational allergen in males. 46% had been in the causative occupation for over 2 years before developing irritant contact dermatitis. Some new occupational allergens have emerged in recent years. OSD in Western Australia does not appear to differ in any major way from that reported from other countries.

An outbreak of occupational dermatitis in an electroforming plant where there was heavy exposure to nickel is described. Patch test investigations confirmed nickel allergy in 13 of 27 exposed individuals. Nickel chloride was found to be a more reliable patch test allergen than nickel sulphate. Improvements in industrial hygiene led to an immediate decrease in the incidence of dermatitis. Persistent patch test sensitivity to nickel was found in three individuals who had been removed from the process chemicals for some years.