Contact Dermatitis 2007: 56: 232–234 Printed in Singapore. All rights reserved # 2007 The Authors Journal compilation # 2007 Blackwell Munksgaard CONTACT DERMATITIS Contact allergy in male construction workers in Sao Paulo, Brazil, 2000–2005 MARZIA SILVA MACEDO,ALICE DE OLIVEIRA DE AVELAR ALCHORNE,ENILDE BORGES COSTA AND FA ´ BIO TADEU MONTESANO Department of Dermatology, Universidade Federal de Sa˜ o Paulo-Escola Paulista de Medicina (UNIFESP-EPM), Brazil There are no recent data on allergens in the construction industry in Brazil; apparently there were no changes in allergenic substances. The objective of this study was to identify sensitization to allergens in adult males working in the construction industry. A cross-sectional study with adult males sub- mitted to patch tests from May 2000 to December 2005. Out of 169 male patients, 83 were construc- tion workers. The five most frequent allergens among the construction workers were potassium dichromate (57%), carba-mix (34.9%), cobalt chloride (30.2%), thiuram-mix (27.9%) and neomycin (19.8%). There is a significant sensitization to potassium dichromate, cobalt, carba-mix, and thiuram-mix, demonstrating that cement and rubber gloves of personal protection equipment still account for allergic contact dermatitis in construction industry workers. Key words: allergic contact dermatitis; metals; occupational; patch test; rubber chemicals. # Blackwell Munksgaard 2007 Accepted for publication 19 December 2006 Allergic contact dermatitis in construction in- dustry workers is one of the most frequent occu- pational dermatoses found in almost any country (1). The most important allergenic substances for these workers are potassium dichromate (chro- mium), cobalt chloride (cobalt), and rubber com- ponents used in personal protection equipment (PPE), such as carbamates (‘carbas’), mercapto- benzothiazoles (‘mercaptos’), or thiuram group substances (‘thiurams’) (1). Furthermore, new additives such as resins were been introduced in the construction industry and became new sensi- tization sources (1, 2). The prevalence of allergy in the construction industry varies according to the region studied (1). These differences are related to the natural occurrence of ore allergens in cement manu- facturing, significant variability of industrial pro- cesses, use of medical and cosmetic products by workers or habits from each region or country studied (3). There are no recent data on allergens in the construction industry in Brazil; apparently there have been no changes in allergenic substances, contrary to what is happening in more socially and economically developed countries, where the use of ferrous sulfate has been adopted to decrease sensitization to chromium and precautions have been taken in rubber manufacturing (1, 4–6). Objective To identify the main allergens in construction workers seen at the Outpatient’s Clinic of Skin Allergy and Occupational Dermatoses, Depart- ment of Dermatology, Universidade Federal de Sa ˜o Paulo-Escola Paulista de Medicina (UNIFESP- EPM). To verify if chromium and rubber aller- gens from PPE are still the main allergens in these professionals seen at this clinic. Methods We conducted a cross-sectional study analyzing the medical records of all patients seen for the first time by the Group of Skin Allergy and Occupational Dermatoses, Department of Der- matology, Universidade Federal de Sa ˜o Paulo- Escola Paulista de Medicina (UNIFESP-EPM), from May 2000 to December 2005, who were submitted to patch tests with the standard series of the Brazilian Contact Dermatitis Research Group (GBEDC) (3). The substances used in the standard series are supplied in polypropylene syringes by the FDA – Allergenic Laboratory (Rio de Janeiro).