Dermatosis profesional por resina epoxi: Presentación de un caso clínico / Professional dermatosis for epoxy resin: A clinical case report

Mostramos un caso de dermatosis profesional originado por plásticos (resinas epoxi) y la importancia de la detección precoz. Las resinas epoxi son de gran utilización en todo tipo de industrias (artes graficas, construcción, electrónica, componentes de prótesis traumatológicas, prótesis odontológicas, etc.) y sus componentes pueden ser causa de dermatitis de contacto irritativa y por sensibilización.

We describe a case of professional dermatosis caused by exposition to plastic products (epoxy resin) and importance of early detection. The epoxy resins are widely used in all types of industries (graphics arts, construction, electronics, traumathological and odontological prothesis, etc.) and their components may be the cause of contact dermatitis and sensitivity. Risk factors at work with epoxy resins are present during the production base resins, hardening agents, plasticizers and dilutants increase the risk of exposition at work. This requires preventive measures and early diagnosis.

Analysis of toxic gas produced by heating tar epoxy resin paint to assess work atmosphere.

Two male workers were acutely intoxicated with gas produced by heating tar epoxy resin paint, and developed peripheral neuropathy. To assess the work atmosphere, we analyzed the degradation products by GC-MS. The major toxic products emitted by heating tar epoxy resin were hydrogen cyanide, phenol, and benzene, as well as naphthalene. From 1 m2 of the surface of steel plates painted with tar epoxy resin, 2.4 g of hydrogen cyanide, 9.6 g of benzene, and 1.2 g of nephthalene were produced by heating at 1000 degrees C, At 700 degrees C, the amounts of phenol and p-isopropylphenol produced were 3.7 g and 0.57 g, respectively. Based on these results and the area of steel surface burned, the concentration of hydrogen cyanide, benzene, and phenol in the atmosphere of work environment was estimated to be 16, 64 and 24 mg/m3, respectively. Some of the symptoms of the workers including peripheral neuropathy might be related to the sole or cooperative action of the foregoing toxic chemicals mentioned above.

Protective effect of barrier creams and spray coatings against epoxy resins.

This study evaluates the protective capacity of 4 barrier creams and 2 methacrylate spray coatings against skin contact with epoxy resins. The effect of these materials on the strength and on the surface area of patch test reactions caused by epoxy resin was assessed in 11 volunteers with a known allergy to epoxy resins. Standard amounts of barrier cream and spray coating were applied on the skin. Then patch tests were carried out with epoxy resin on the pretreated sites. After 24 h patches were removed, 48 h thereafter the strength and surface area of the reactions were scored. Results were compared with the score of a control test. The use of 2 barrier creams resulted in a significant reduction of the surface area of the patch test reactions. Spray coatings significantly reduced both the strength and the surface area of the reactions. Our results suggest that methacrylate spray coatings and barrier creams may provide protection against epoxy resins during a test period of 24 h. However, the development of new formulations, adapted more specifically to this purpose, is necessary.

Pulmonary haemorrhage and haemolytic anaemia due to trimellitic anhydride.

Two young men who had been exposed at work to epoxy resin powder containing trimellitic anhydride (TMA) presented with haemolytic anaemia and repeated haemoptyses. They did not return to work at the factory and the symptoms and the anaemia resolved spontaneously. Seven similar cases have lately been presented at meetings, so it seems that TMA, already known to cause respiratory syndromes such as asthma, can also lead to several extrapulmonary toxic effects, including haemoptyses and haemolytic anaemia. Studies on these patients' sera with TMA haptenised protein and cells pointed to an immunological mechanism.

Asthma due to inhaled chemical agents--epoxy resin systems containing phthalic acid anhydride, trimellitic acid anhydride and triethylene tetramine.

Six workers with a diagnosis of occupational asthma and one with chronic bronchitis were examined for sensitivity to epoxy resin systems and certain of their components. In six cases the chemical agent responsible for their symptoms was identified by careful inhalation challenge testing, simulating their exposure at work and thus providing a precise aetiological diagnosis. In one worker asthma followed exposure to triethylene tetramine fume; four were sensitive to acid anhydrides, three to phthalic acid anhydride as a fume or powder and one to trimellitic anhydride. On worker thought to be sensitive to toluene di-isocyanate gave negative reactions to this and positive reactions to a phthalic acid anhydride epoxy resin and another thought to have asthma from acid anhydride fumes was found to be sensitive only to toluene di-isocyanate. Immediate, non-immediate or combined asthmatic reactions were elicited.