Aflatoxins are Toxic: Fungal metabolites found in some fungis
Aflatoxins are a toxic metabolite of certain fungi like Aspergillus flavus and Aspergillus parasitosis. Different types of aflatoxin have varying degrees of harmfulness—ranging from being cariogenic to causing birth defects. Profoundly impacting warm regions with higher humidity, these fungi contaminate agricultural crops like corn, figs, tree nuts, cocoa beans, and dates.
You can become exposed to aflatoxin by eating foods contaminated with aflatoxin. Livestock is also susceptible to exposure if they eat contaminated feed. The FDA tests foods for aflatoxin, especially imports from warm and humid regions. The highest concern for contamination is in corn, a staple in many diets and common feed for animals.
According to Cornell’s College of Agricultural and Life Sciences, aflatoxin contamination is favored by “high temperatures, prolonged conditions of drought, and high insect activity” during the growing season. After harvest, production of aflatoxin increases
with humid conditions.
Aflatoxins are a heavily researched mycotoxin because of its potent carcinogenic effects to the liver and other effects to humans. Mycotoxins are mold toxins. Acute aflatoxicosis from large doses aflatoxins causes damage to the liver. Long-term exposure to aflatoxins can cause birth defects in children, immunosuppression, and liver cancer. Countries like Taiwan, Uganda, Tanzania, and India, have a higher risk for chronic exposure to aflatoxin.
In order to minimize eating foods contaminated with aflatoxin, the World Health Organization recommends doing to following:
- Buying grains and nuts as fresh as possible
- Buying only reputable brands of nuts and nut butters (aflatoxin molds are not entirely killed by processing or roasting, so can show up in products e.g. peanut butter)
- Making sure that foods are stored properly and are not kept for extended periods of time before being used
- Trying to ensure his/her diet is diverse (consumers who lack dietary diversity need to pay extra attention to minimize the risk of high exposure to aflatoxins). 
For more information about food safety, food poisoning, or to speak to a food poisoning lawyer.