Toxicants Of Plant Origin PDF Download

Most of the non-nutrient chemicals humans ingest with their normal diet are naturally occurring secondary metabolites of food plants. Quantitatively, exposures to these plant-specific constituents may significantly exceed dietary exposures to most of the synthetic chemicals, which may intentionally or unintentionally occur in food. Some of them have been shown to be highly potent toxins. It has been proposed to define inherent plant toxicants as plant constituents, which might induce adverse effects in humans when the plant or plant products are consumed. Examples are glycoalkaloids in potatoes, cyanogenic glucosides in cassava or phytohemaglutinin in red kidney beans. They have all been causally associated with acute human toxicity when ingested through foods that were not properly processed or prepared. Both toxicological and exposure data are limited for most inherent plant toxicants. Therefore, accurate risk assessment is often not possible. For many inherent toxicants the margin of exposure between toxic levels in humans and actual exposure from food is low. Therefore risk management measures need to be implemented in order to ensure food safety. Management options include development of cultivars low in inherent toxicants, agricultural and storage practices, and food processing. Further work is necessary to better characterize the potential health impact of inherent plant toxicants. This should include the development of a risk assessment paradigm which considers both potential adverse but also beneficial effects of secondary plant metabolites and of the pertinent food plants as such.