Understanding Aflatoxin

A mycotoxin, a family of toxic compounds derived from molds growing on foods and on grains used for animal feed. Aflatoxin is produced by ASPERGILLUS, a storage mold that often infests damp grains and nuts. Nuts such as PISTACHIOS, ALMONDS, WALNUTS, PECANS, and PEANUTS are susceptible to MOLD. Very low levels of aflatoxin often contaminate PEANUT BUTTER. Spot checks have shown that this contamination is usually below the U.S. Food and Drug Administration limit. In the 1970s and again in the 1980s, hot drought conditions caused outbreaks of mold in corn and, consequently, widespread aflatoxin contamination.
Concern has focused on aflatoxin because it is a potent liver CARCINOGEN. The amount of aflatoxin permitted by the U.S. FDA is 15 parts per billion, although levels as low as one part per billion can cause liver cancer in certain species of experimental animals. As yet there is no compelling evidence that aflatoxin consumption in the low amounts usually encountered in Western nations causes cancer. In regions of Africa where peanut consumption and consequently aflatoxin intake is very high, population studies suggest a correlation with liver cancer in humans. Recent epidemiological studies have shown that ingestion of aflatoxin B-1 increases the risk of developing liver cancer. The risk is even higher for people who are infected with hepatitis B. In addition to increasing the risk of chronic diseases such as cancer, ingestion of aflatoxin B-1 can cause acute symptoms of aflatoxicosis, including vomiting, abdominal pain, and even death.
Consumers should avoid moldy, discolored, or off-flavor nuts. Molds and fungi send out microscopic filaments beyond the immediate, visibly moldy area and cannot be easily removed. Furthermore, aflatoxin is not completely destroyed by cooking. Therefore moldy food (except cheese) should be discarded, rather than cutting out the mold.