Paints, lacquers, and varnishes in occupational dermatology

Abstract

Although the risks of allergies or irritation are highest for those who are most consistently in contact with paints over a prolonged period, such as painters, people with more acute exposures such as residence dwellers in a newly painted home may also be at higher risk. Even public places where painting is being done could potentially be a health hazard both for the workers and the general public. Water-based paints require important additives (e.g., preservatives) which are often the cause of an irritant or allergic reaction. Minute amounts of an additive may induce a potent allergic reaction. Volatile paint ingredients, including preservatives of the isothiazolinone class and synthetic resins such as epoxy resins and isocyanates, may cause respiratory and other nondirect contact symptoms of allergic dermatitis. As allergens, the most problematic recent isothiazolinone is methylisothiazolinone (MI); others include methylchloroisothiazolinone (MCI), octylisothiazolinone (OIT), benzisothiazolinone (BIT), and butylbenzisothiazolinone (BBIT). The most problematic recent epoxy resin is diglycidyl ether of bisphenol A resin (DGEBA-R); diglycidyl ether of bisphenol F (DGEBA-F) is also a significant allergen. Both aromatic and aliphatic isocyanates may be volatile, causing asthma, airway irritation, and hypersensitivity pneumonitis; although polyisocyanates based on hexamethylene-1,6-diisocyanate (HDI) are less volatile. Allergic reactions may take repeated exposures over months to years before symptom manifestation. Allergens are also found in other products (e.g., MI is commonly used as a preservative in cosmetics). Cross-sensitization between products within the same class can occur, but co-existing reactions may be due to co-exposure and not cross-sensitization.