Distributions of IgE levels were determined from 312 children (divided into three age groups), living in small Austrian towns with different levels of air pollution. The spread of IgE concentration was extremely wide; the mean value was 124 kU/I with a standard deviation of 240. An increase of concentration was found in the group aged 6 to 11 years. No significant difference was found according to sex and the higher rates of IgE. The reference rates were then used to compare children living in an industrial region with heavy metal production. A significant difference was found in the lower IgE concentrations (25th and 50th percentiles).