Incidence rates of occupational allergic contact dermatitis caused by metals.

BACKGROUND: Data on the incidence rates (IR) of occupational dermatoses are scarce. MATERIAL AND METHODS: We calculated the IR of occupational allergic contact dermatitis (ACD) caused by chromium, nickel and cobalt by occupation, during a 7-year period (1991-1997) from the data of the Finnish Register of Occupational Diseases and from the statistics on the working population in different occupations. RESULTS: A total of 2543 cases of occupational ACD were reported during 1991-1997. Cr caused 143 (5.6%) cases of ACD, Ni 176 cases (6.9%) and Co 41 cases (1.6%) of ACD. Women had greater number of occupational ACD from nickel, whereas occupational ACD from chromate and cobalt was more frequent in men. The ranking list of the IR of occupational ACD caused by Cr per 10,000 working years was (incidence rate in parenthesis) (1) tanners, fellmongers, and pelt dressers (12.20); (2) cast concrete product workers (6.94); (3) leather goods workers (4.71), (4) metal plating and coating workers (3.66); (5) bricklayers (3.44); (6) reinforcement concreters (2.79); and (7) building workers (1.32). The corresponding ranking list for Ni was (1) footwear workers (2.55); (2) machine and metal product assemblers (2.40); (3) electrical and teletechnical equipment assemblers (2.03); (4) precision instrument mechanics (1.73); (5) postal officials (1.48); (6) hairdressers, beauticians, and bath attendants (1.24); (7) industrial tailors and seamstresses (1.08); and (8) waiters in cafes and snack bars (1.04). The corresponding ranking list for Co was (1) printers (0.80); (2) turners, machinists, and toolmakers (0.36); and (3) machine and engine mechanics (0.17). CONCLUSION: The Finnish Register of Occupational Diseases forms a good basis for calculating IR. As IR illustrates the risk to become sensitized, preventive measures should be directed at occupations with the highest IR.     

FS12.1Allergic contact dermatitis from plastic gloves

Plastic gloves are made of polymers including polyvinylchloride, polyvinylalcohol, polyethylene and polyvinylacetate. Additives such as plasticizers, stabilizers, UV light absorbers, fungicides, bactericides, flame retardants and colourants are added to the polymer, and these are potential allergens. Contact allergy to plastic gloves is rare. The allergen responsible for the sensitization usually remains unknown. An organic pigment, Irgalite Orange F2G, and bisphenol A have both caused contact allergy from household‐type PVC gloves. 1 patient with allergic contact dermatitis from his PVC gloves reacted also to tricresyl phosphate and triphenyl phosphate, chemicals known to be used as plasticizers in PVC. A plasticizer, di(2‐ethylhexyl) phthalate (DOP), caused 1 case of contact urticaria from the vinyl chloride slip guard of cotton gloves. 1 patient with contact urticaria from his polyethylene gloves reacted to 3 antioxidants, octadecanoic acid methyl ester and di‐tertiary butyl phenol of the gloves on scratch testing. We report 3 additional cases of allergic contact dermatitis from PVC gloves due to bisphenol A. 2 of the patients reacted also to para‐tertiary butyl catechol, a polymerization inhibitor in PVC. In chemical analysis, the connection between sensitization to para‐tertiary butyl catechol and the use of vinyl gloves could not be proven. We analysed 16 brands of disposable PVC gloves for medical use, covering at least 80% of the Finnish market. We found a very small amount of bisphenol A in 1 brand, and no para‐tertiary butyl catechol in any of the gloves. However, bisphenol A should be remembered as a possible allergen in PVC gloves.     

Occupational dermatitis due to an epoxy acrylate

A dental assistant developed sensitivity to denial restorative materials within 3 months of starting to use them. They contained the epoxy acrylate BIS-GMA, which is the most commonly used dimethacrylate monomer in dental composite restorations. She was positive to a patch test with BIS-GMA, which was the probable allergen, and epoxy resin, but this substance was not present in the materials used, LIS shown by high performance liquid chromatography. The patient was also allergic to the disinfectant Desimex i® containing dodecyl diaminoethyl glycine.