Sensitizing and irritant properties of 3 environmental classes of diesel oil and their indicator dyes

3 dyes, Solvent Yellow 124 and Solvent Blue 79 or Solvent Blue 98, were added to diesel oils in Sweden for identification of their particular use and taxation bracket in late 1993. Health concern regarding the toxicity of the dyes resulted in several reports to the Worker Inspection Bureau. 36 men reporting skin disease supposedly caused by dyes were diagnosed to have irritant reactions, irritant contact dermatitis or exacerbation of other skin disease. Tests on 15 individuals from this group, and 20 healthy volunteers, failed to demonstrate contact allergy or contact urticaria to the dyes or dyed diesel oil. Patch tests with dyes (10% v/v) in pet. did not cause irritation. Tests of irritant properties of the diesel oils showed that the old type of oil, with high viscosity, high content of aromatic compounds and moderately high sulfur content, caused little irritation, whereas newer, lighter qualities of diesel oil, with low concentrations of aromatic compounds and low sulfur content, which cause less pollution to the environment when burnt, were significantly more irritant to the skin and probably a cause of the skin problems.