Contact sensitization in car mechanics with occupational dermatitis. IVDK data, 2008-2012 [Kontaktsensibilisierungen bei Kfz-Mechanikern mit Berufsdermatose]

Abstract

Background: Car mechanics are occupationally exposed to various contact allergens. However, a comprehensive spectrum of sensitization in car mechanics with occupational dermatitis has not yet been described. Objective: We intended to analyze the spectrum of sensitization in car mechanics with occupational dermatitis. Additionally, by analyzing results of patch tests with working place products, respective recommendations should be evaluated and improved, if necessary. Material and methods: Retrospective analysis of data of the Information Network of Departments of Dermatology (IVDK), 2008-2012. In this time period, 120 car mechanics with occupational dermatitis were patch tested. In 56 of them, workplace products were tested in 594 single patch tests. Results: No statistically significant accumulation of type IV-sensitizations to particular allergens could be found; however, there was a trend towards an increased frequency of sensitizations to nickel, cobalt, methyl(chloro)isothiazolinone (MCI/MI), and N-isopropyl-N′-phenyl-p-phenylenediamine (IPPD). Only complete workplace products, but not their single ingredients were patch tested. In 9 patients, positive reactions occurred, mainly to skin cleansers and skin creams. Motor oil and gearbox oil were tested as is, and 50% and 10% in olive oil. Hydraulic oil was tested as is, 50%, 10%, and 1% in olive oil. Brake fluids were tested as is, and 10% and 1% in water, olive oil, or petrolatum. No irritant reactions were observed in these tests. Discussion: Car mechanics are exposed to nickel and cobalt e.g., by tool handles. IPPD is found in car tyres, whereas MCI/MI and MI are commonly used as preservatives in technical cleaning agents and skin care products. Analysis of patch tests with workplace products gave no hints to previously undetected occupational allergens, but gave clues to adequate test concentrations. Irritant properties of hydraulic oils have possibly been overestimated; test concentrations as with motor oil or gearbox oil should be considered. Patch testing with brake fluids could be done at 10% and 50% in water. Patch tests with silicon spray could be performed at 10% in petrolatum, in analogy to other silicon compounds. Refrigerants from air conditioning systems should not be patch tested. © 2014 Dustri-Verlag Dr. Karl Feistle.