M10.1 EPIDEMIOLOGY AND PREVENTION OF OCCUPATIONAL CONTACT DERMATITIS

T. L. Diepgen.Department of Social Medicine, Occupational and Environmental Dermatology, University of Heidelberg, Germany

Occupational contact dermatitis (OCD) has the highest ranking of all occupational diseases in many countries. The incidence rate is believed to be around 0.5–1.9 cases per 1000 fulltime workers per year. However, the true incidence of work related hand eczema (mostly irritant hand eczema) is highly underreported. The development of OCD is determined by a combination of individual susceptibility (endogenous factors) and exposure characteristics (exogenous factors). Skin contact with irritants and/or allergens is a necessary condition of contact dermatitis and the probability and severity of a reaction depend on the type and intensity of exposure. Epidemiological studies play an important role in observing disease trends, analysing risk factors, and monitoring the effect of preventive measures. Occupational Contact Dermatitis (OCD) has become an issue of increasing importance worldwide, not only because of cost intensification for employers but also because of impairment to employees’ quality of life. This lecture summarises some important causes of occupational contact dermatitis in Europe, demonstrates possibilities of prevention, and ends by highlighting important future health service and population research issues. The following questions will be discussed:

• How common is OCD in different industries and what is the extent of underestimation?

• What are the causes of OCD?

• How should we deal with high risk individuals (atopics)?

• What regulations are needed to prevent OCD?

• What is the future of research and service development?

Research into the causes and prevention of occupational contact dermatitis using an epidemiological approach is still in its infancy, yet already there are some pointers that OCD can be prevented effectively

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M10.2 ANALYSIS OF 1591 PATIENTS ATTENDING AN OCCUPATIONAL DERMATOLOGY CLINIC

R. Nixon, K. Frowen.Occupational Dermatology Research and Education Centre, Skin and Cancer Foundation, Carlton, Victoria, Australia

Introduction: The Occupational Dermatology Clinic started in 1993 and the results of the first 1591 attendees are presented. We have developed a database (the Contact Allergy Management System), which has also been adopted by other Australian patch test clinics.

Methods: Details and diagnoses of patients attending the clinic are recorded. Consent to store data is obtained at clinic attendance, where patients usually attend on three occasions over a 5 day period for epicutaneous patch testing to detect delayed hypersensitivity skin reactions. The information is stored in a de-identified format.

Results: Of the study group, 964 (60.6%) had significantly work related disease and 311 (19.5%) had partially work related disease. There were 930 (58.5%) men, 661 (41.5%) women, and 1097 (69.0% had hand dermatitis. The most common primary diagnoses were irritant contact dermatitis (ICD) (567; 35.5%), allergic contact dermatitis (ACD) (497; 31.3%), endogenous eczema (EE) (282; 17.7%), psoriasis (53; 3.4%), latex allergy (LA) (32; 2.0%), and contact urticaria (not caused by latex) (31; 2.0%). All diagnoses were made by the same occupational dermatologist (RN). There were 819 (51.5%) with one diagnosis but 770 (49.4%) had multiple diagnoses, including 29 with four diagnoses; for example, ACD, LA, ICD, and EE. There were 596 (37.5%) patients diagnosed with atopy who were more likely to have occupational contact dermatitis (OCD) (p<0.001) and ICD (p<0.05), but not ACD. The most relevant allergens were, in order, thiuram mix (rubber accelerator), chromate (used to tan leather and in cement), p-phenylenediamine (in hair dye), epoxy resin, ammonium persulphate (bleach), and nickel, and the most common irritants were detergents and soap, wet work, solvents, cutting oils, and heat and sweating. Rates of OCD for 1993–003 per 1000 workers based on Australian Bureau of Statistics data were 5.6 for hairdressers, 4.5 for machine operators, 2.5 for metal workers, 2.2 for construction workers including bricklayers and concreters, 2.0 for healthcare workers, and 1.7 for food handlers.

Conclusions: Our experience over 11 years has enabled us to identify important occupational allergens, irritants, and high risk occupations, as well as highlighting the role of a background of atopy. This has informed us in the development of specific programs to reduce OCD.

M10.3 MATERIAL SAFETY DATA SHEETS: REPORTING OF SKIN SENSITISERS AND SKIN SENSITISATION

T. Keegel^1,2, A. S. Fletcher², J. Cahill¹, R. L. Nixon¹, S. Sakata³, M. Moyle¹, A. D. La Montagne².¹Occupational Dermatology Research and Education Centre, Australia; ²Department of Public Health, The University of Melbourne, Australia; ³Faculty of Medicine, Monash University, Australia

Introduction: Most studies of Material Safety Data Sheets (MSDS) examine readability, uptake, or accuracy. Few studies have tested the hypothesis that MSDS warning information prevents the associated exposure and disease.

Objective: To test the relationship between correct identification and listing of a sensitiser and skin sensitisation, among a population of workers with suspected occupational skin disease.

Methods: Between 1/1/01–30/9/03, 705 workers attended the tertiary referral Occupational Dermatology Clinic, Melbourne, Australia. Workers who presented an MSDS for a product which contained a sensitiser, whether listed or not, were included in the study. The sensitiser was either listed on the MSDS or determined by follow up with the product manufacturer. Accuracy of the MSDS with respect to the reporting of skin sensitisers was compared between workers who were sensitised (cases) and non-sensitised (controls). Sensitisation was determined by a positive patch test result to a sensitiser contained in the product. Association between sensitisation and presence of the generic warning “hazardous according to the criteria of WorkSafe/NOHSC Australia” was also assessed.

Results: MSDS from 130 (18.4%) workers were included in the study. Of these, 45 (34.6%) workers were sensitised and classified as cases, with the remaining 85 workers classified as controls. Amongst the 57 (43.8%) who presented accurate MSDS, 29 (50.8%) were sensitised. For the 73 workers with MSDS which did not list sensitisers, 16 (21.9%) were sensitised. An increased rate of sensitisation was observed amongst cases with MSDS reporting sensitisers, (odds ratio 3.6; 95% confidence interval 1.61 to 8.49). However, no increased rate was observed for the presence of the generic warning.

Conclusion: MSDS were largely inaccurate in reporting skin sensitisers. Protective effect for the presence of a skin sensitiser warning was not observed. Rather, the presence of a skin sensitiser warning was significantly associated with worker sensitisation, which is currently being investigated by developing measures of relative potency for inclusion in analyses.