Higher frequency of atopic dermatitis and decrease in viral warts among children exposed to chemicals liberated in a...

In february 1993, a major accident occurred in a chemical plant in Frankfurt, Germany, resulting in the emission of a cloud containing 10 m3 of chlorinated and azo compounds such as o-nitroanisole. An inner zone of the suburb Schwanheim was severely polluted.

To assess possible long-lasting effects of this environmental accident on the incidence of skin diseases, we examined a total of 511 children from the inner and outer zones of Schwanheim 18 months later and compared the findings to those obtained from a control group of 143 children from the Frankfurt area and South Hessen. For 402 children of the exposed group, information about the exposure status was available, clearly defining presence of absence in the inner zone at the time of the accident.

We observed an overall increase in atopic dermatitis among children present during the accident with an odds ratio of 2.44 (95% CI: 1.25-4.76, p value = 0.009). The prevalence of atopic dermatitis was most marked among exposed children in the age group of 6-12 years with a peak of 22.1% compared to 9.2% in the control group and 11.7% among non-exposed children from the outer zone. All cases of atopic dermatitis were mild, however, and did not require hospital treatment. A history of atopic dermatitis was obtained in 20.3% of all children. In the inner zone, 34.2% of the present cases with atopic dermatitis had a previous history of this disease compared to 31% in the outer zone and only 16.2% in the control group. Other skin diseases, such as birthmarks, congenital skin tumours, psoriasis or acne, did not differ, except for viral warts (verrucae vulgares), which were much more frequent in the control group.

The data suggest that acute exposure to a major chemical burden is a risk factor that contributes even after the considerable time period of 1.5 years to the exacerbation of latent and also the development of 'new' atopic dermatitis.