GBZ 20-2019Diagnosis of occupational contact dermatitis (English PDF)

4.1 Occupational irritant contact dermatitis

Acute dermatitis presents erythema, edema, papules; or dense papules, blisters, or bullae on the basis of edematous erythema. After blisters breaking, it shows erosion, exudate, and scabbing. Self-conscious burning pain or itch.

Chronic changers present varying degrees of infiltration, thickening, desquamation, or chap. It can be diagnosed if:

Seborrheic dermatitis

A chronic skin inflammation which develops on the basis of seborrhea.

It often distributes in parts with many sebaceous glands, such as the scalp, face, chest, back, armpits, etc.

The skin lesions are slightly-yellowish mild erythema, with greasy scales and scabbing.

Occupational photo-contact dermatitis

Skin inflammation reaction caused by contact with photosensitive substances and exposure to sunlight in occupational activities.

It is confined to the light- irradiated part or begins at the contact position;

and then spreads to the surrounding area; may spread to the whole body.

Flushing, swelling with burning, pricking, and itching appear at the light- irradiated parts. In severe cases, on the above basis, bullae, erosion, and scabbing appear.

A.2 Occupational contact dermatitis currently lacks specific auxiliary

examination indicators. The diagnosis is mainly based on clinical data. When the occupational history is clear; there is a close causal relationship between occupational contact and the occurrence and development of skin lesions; and contact dermatitis and other diseases caused by non-occupational factors can be eliminated, diagnosis shall be performed.

A.3 When inquiring about occupational history and conducting on-site

investigations, attention shall be paid to the effect OF changes in contactant, contact dose and contact mode, workplace environmental health (including production facilities and layout, ventilation and exhaust, dust removal, workshop temperature and humidity, etc.), occupational protection, personal hygiene, individual specificity, and seasonal factors, etc. ON the occurrence and development of this disease.

A.4 The skin patch test is currently one of the most important methods for detecting sensitizers of allergic contact dermatitis. It is suitable for occupational allergic contact dermatitis and not for occupational irritant contact dermatitis.

During the operation, attention shall be paid to the concentration of the patch material. Appropriate excipients shall be selected. The results of the patch test shall be correctly evaluated (see GBZ 18).

A.5 Occupational contact dermatitis is classified into irritant and allergic types.

During diagnosis, they shall be separated as much as possible, to facilitate the identification of work ability. However, some pathogenic substances have both irritating and sensitizing effects. When it is clinically difficult to distinguish or both effects exist, it can be diagnosed as occupational contact dermatitis and treated according to occupational allergic contact dermatitis.

A.6 If the occupational allergic contact dermatitis repeatedly occurs, has no improvement in the long term so that work is affected, the job can be changed, to get rid of the environment containing sensitizers.

Appendix B (Informative)

Common pathogenic substances of occupational contact dermatitis

B.1 Irritating effect-based pathogenic substances

B.1.1 Inorganic primary irritants: acids such as sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, chlorosulfonic acid, hypochlorous acid, chromic acid, etc. Alkalis such as potassium hydroxide, sodium hydroxide, ammonium hydroxide, sodium carbonate, etc. Certain metals and their salts such as antimony and antimony salts, arsenic and arsenic salts, dichromate, zinc chloride, gallium chloride, beryllium fluoride, etc.

B.1.2 Organic primary irritants: organic acids such as acetic acid, formic acid, salicylic acid, phenol, etc. Organic alkalis such as ethylenediamine, propylamine, butylamine, etc. Organic solvents such as turpentine, carbon disulfide, etc.

B.1.3 Petroleum and its products, including asphalt, tar, various lubricating oils, etc.

B.1.4 Organohalogen compounds, such as polychlorinated biphenyls, chlorophenols, and chloronaphthalenes, which have special irritating effects.

B.1.5 Animals: pine caterpillars, mulberry caterpillars, rove beetles, bees, mites, ticks, leeches, jellyfish, etc.

B.1.6 Plants: figs, Centipeda minima, lavender, mint, ivy, ailanthus, safflower

(saffron), etc.

B.1.7 Pesticides: insecticides (dichlorvos, trichlorfon, isocarbophos, methamidophos, dimehypo, benzofuranone, etc.), acaricides, fungicides, and herbicides (paraquat), etc.

B.1.8 Other: glass fiber, asbestos, soap, synthetic detergent, flux, depilatory

agent, disinfectant, hair dye, etc.

B.2 Allergic reaction-based pathogenic substances

B.2.1 Dyes (pigments) and their intermediates: dark reddish purple, Lithol Red, basic red, disperse blue 106, disperse blue 124, naphthylamine yellow, fluorescent dyes, dyes in modern beauty products, p-phenylenediamine, m-

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