Cottonseed, an oilseed, is used as animal feed in the southwestern part of the United States. Cottonseed meal is used more widely for both cattle and poultry. When in interstate commerce, these products are subject to Food and Drug Administration action guidelines: 20 ppb aflatoxin in cottonseed and cottonseed meal and 0.5 ppb aflatoxin M1 in milk. Not all cottonseed-producing areas report the same problem reported here. It should also be noted that aflatoxin contamination, in general, is a sporadic problem.