natural toxins

Potent toxins and carcinogens are present in the natural environment.

These mycotoxins and phytotoxins may contaminate foods. For example, cycad flour is used in arid climates. This plant contains the toxin cycasin (methylazoxymethanol β-glucoside).

If the plant and seeds are cut into small pieces, soaked in water, and dried, the toxin is leached. However, if these precautions are not followed, a degenerative neurologic disorder (amyotrophic lateral sclerosis) is produced by ingestion of cycasin. Animal toxins can be ingested by eating fish, snails, or mollusks.

The most common poisoning results from eating tropical fish and snails that have ingested dinoflagellates containing ciguatoxin. Ciguatera poisoning can be severe and occurs in the South Pacific and the Caribbean.

Paralytic shellfish poisoning occurs in North America after eating mollusks that have ingested dinoflagellates that contain saxitoxin.

Aflatoxin B1 is produced by fungi that contaminate peanuts, corn, and cottonseed. It is a potent carcinogen that contributes to the high incidence of liver cancer in some regions of Africa and the Far East.