Occupational dermatoses caused by contact with metalworking fluids in the region of Central Slovakia between 2000 and 2012

Metalworking fluids (MWFs) are a common cause of allergic and irritant contact dermatitis. MWFs being currently used are mostly water based, containing biocides, emulsifiers, and other additives.We performed a retrospective analysis of the etiology of the occupational dermatoses caused by metalworking fluids in three regions of Central Slovakia (population of approximately 2 million) between 2000 and 2012. The primary aim was the analysis of metalworking fluid-induced dermatoses, which involved determining the particular disease type (allergic or irritant), its regional distribution, and the specific chemical causing the disease. The secondary aim of the study was to assess the level of knowledge and competence among dermatologists in performing patch testing for allergens contained in metalworking fluids using a study-specific questionnaire.Of the total number of 422 dermatoses during the analyzed period, 64 (41 in men and 23 in women) were caused by metalworking fluids. The implicated fluids were all aqueous, synthetic MWFs. 39 patients developed an allergic and 25 an irritant-induced contact dermatitis. 51 patients were tested using a special Trolab® metalworking battery (Almirall Hermal GmbH, Reinbek, Germany). The test identified a positive reaction to one of the following chemicals: methylchoroisothiazolinone/methylisothiazolinone (MCI/MI), formaldehyde, 1,2-benzisothiazoline-3-one, abietic acid, chloroxylenol, triclosan, amerchol L101, dichlorophene, propylenglycol, metylene (bis-methyl oxazolidine), monoethanolamine, and diethanolamine. The questionnaire showed that a large majority of Slovak dermatologists have no experiences with testing of MWFs.Metalworking fluids were found to be the most frequent cause of occupational contact dermatitis. They also are the second largest group of all occupational dermotoses. Their incidence corresponded with the presence of machine industry in the region. Several unresolved problems include detection of specific allergens and standardization of patch test performance among individual dermatologists. Low levels of experience in testing of MWFs revealed need to educate both dermatologists and residents.