Contact dermatitis is an eczematous eruption caused by external agents, which can be broadly divided into irritant substances that have a direct toxic effect on the skin (irritant contact dermatitis, ICD) and allergic chemicals where immune delayed hypersensitivity reactions occur (allergic contact dermatitis, ACD). Contact urticaria is an immediate reaction from exposure to a substance and is mediated by either irritant or immunological mechanisms; it can resemble ICD but the onset is immediate and short lived. Many allergenic chemicals are also irritants and it is thought that ICD enhances the development of ACD.¹ ICD is the commonest presentation of occupational skin disease.² In industries where workers engage in wet work, almost all workers develop some degree of irritant contact dermatitis. Most workers with mild occupational irritant contact dermatitis do not seek medical attention and accept the condition as an occupational hazard. A better understanding of irritant contact dermatitis will lead to improved management of this common condition.

INCIDENCE AND PREVALENCE

Dermatitis is a common condition that is reported to affect 5–9% of men and 13–15% of women.² Occupational skin disease accounts for up to 30% of all cases of occupational illness in industrialised countries.³ The overall annual incidence of occupational contact dermatitis (OCD) from reports by dermatologists and occupational physicians to EPIDERM estimated levels at about 1.3 cases per 10 000 workers,⁴ manufacturing industries accounting for the greatest number of cases seen, followed by healthcare employment. The economic impact of OCD is considerable. Approximately 4 million working days are estimated to be lost every year due to absenteeism resulting from work related skin diseases.¹ This can be costed at approximately £200 million. During 1996, dermatological problems accounted for 23.4% of all work related health problems reported to UK occupational physicians. In addition to its economic impact, OCD …