The presence of ochratoxin A (OA) in human milk samples from different regions in Norway was investigated to determine the level of infant exposure to OA from human milk. OA was found in 38 (33%) of 115 human milk samples (range 10-130 ng l(-1)). It was found that 2-26% of the samples contained more than 40 ng l(-1) OA, which will cause a daily intake of OA from human milk exceeding the suggested tolerable dose of 5 ng kg(-1) body weight. Significant regional differences were found.
Investigations from several European countries indicate that, in former days, there was a connection between mycotoxins, mortality and reduced birth rate. In addition to being acutely toxic, many mycotoxins can interfere with the immune system, even in small concentrations. While tuberculosis was declining in Norway as a whole around year 1900, it culminated in Finnmark county. In addition, infant mortality was high. These people in the North ate rye flour imported from Russia, and harvested, transported and stored under conditions which may have favoured growth of toxic fungi. The mycotoxin ochratoxin A has been surveyed in several countries. The level in human sera seems to indicate continuous, widespread exposure of humans to ochratoxin A. Mycotoxin contamination of food and feeds may be a health problem of unknown dimensions.