Allergic contact dermatitis (ACD) is a delayed type IV or cell-mediated hypersensitivity. The diagnosis of ACD is confirmed with patch testing. [LaDou, p. 283-5]
The following two tables illustrate some of the more common occupational contact allergens and the occupations most commonly affected by them. The occupations listed generally have the highest incidence rates of both allergic and irritant contact dermatitis.
The two tables are based on Chapter 15, "Occupations Commonly Associated with Contact Dermatitis" in Marks & DeLeo, plus additions based on recent published reports indexed in Medline.
1 Contact urticaria is an immediate, type 1, antibody-mediated hypersensitivity. It appears within minutes of contact and disappears within a few hours.
2 Creosote is different from the other chemicals listed in that it causes a photoirritant contact dermatitis. There are also several foods that can cause this type of reaction, including lime, celery, parsnip and fig.
Other occupations with exposures to skin sensitizers: Morticians and embalmers (formaldehyde, glutaraldehyde and rubber chemicals); Foundry workers (formaldehyde, isocyanates and amines); Welders (colophony flux, chromium and nickel); Photo processors (Metol, thiourea, CD-2,CD-3, CD-4, formaldehyde, phenidone, phenols and amines)