Hepatocarcinogenic Material in Urine Specimens From Humans Consuming Aflatoxin2

Extracts of urine specimens collected from human subjects known to have consumed an average of 21 µg aflatoxin B1 during a 2-day collection period were fed to rainbow trout, Salmo gairdneri. The quantity of hepatocarcinogenic aflatoxin-like material in the extracts was estimated to be equivalent to that contributed by the small quantity of aflatoxin M1 excreted. These results suggested that the major fraction of aflatoxin ingested by humans was not excreted as aflatoxins B1, M1, or P1 but rather as relatively noncarcinogenic metabolites or conjugates thereof.