Allergens are responsible for only about 25% of occupational contact dermatitis.

 

Recognizing allergic causes is important because it makes possible effective treatment and prevention.

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.

 

 

Source of Information in Tables

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.

¹Contact urticaria is an immediate, type 1, antibody-mediated hypersensitivity. It appears within minutes of contact and disappears within a few hours.

²Creosote 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)

 

Patch Testing

"The accuracy of the diagnosis depends on the experience , knowledge and skill level of the physician who makes the diagnosis, and on the difficulties in confirming the relationship with an exposure." Patch testing is only about 70% sensitive and 50% specific. A specificity of 50% means that in only 1/2 of the cases can a chemical inducing a positive patch test be established as the cause of the worker's dermatitis. [Kanerva  2004, p. 4]

Suppliers of Patch Test Allergens for Physicians

1. T.R.U.E. Test

2. Chemotechnique

3.Trolab patch test allergens are imported and distributed by:

Omniderm Inc.

997 Seguin

Hudson, Quebec Canada J0P 1H0

Tel: (514) 458-0158

4. The Hermal standardized screening patch-test kit is designed to be used with Finn Chambers:

Allerderm Laboratories

1330 Redwood Way Ste. C 

Petaluma, CA  94954 

1-800-365-6868

www.allerderm.com

 

Important Factors in Glove Selection:

1. The glove polymer that minimizes permeation of the chemicals being handled;
2. The glove thickness that maximizes durability and also provides dexterity and comfort;

Web sites of glove manufacturers who offer technical support:

Ansell chemsafe

Best Manufacturing Company

  Revised May 30, 2018

brownjay@haz-map.com