chapter  19
42 Pages

Analysis of Natural Toxins in Foods

Food is a very complex system consisting of an endless number of high and low molecular substances, mostly of natural origin. A majority of these substances are indispensable for the normal functioning of the human body. On the other hand, food also contains substances, both natural and synthetic (anthropogenic), capable of evoking smaller or bigger health disorders; that is, food can contain toxic substances or toxins. In principle, according to the famous Paracelsus, every substance, even a normal constituent of food may become toxic, if its concentration exceeds the de‘- nite lowest observed adverse effect level (LOAEL) during short time (acute toxicity) or is consumed for a longer period on a somewhat lower level (chronic toxicity). To guarantee the safety of food, it is necessary to control it. Since a majority of poisonous substances are present in food in very low concentrations (usually nanograms or micrograms per gram), this control mostly needs very sensitive, selective, and precise methods of analysis. Usually, it is like searching for a needle in the haystack. During last decades, fast development of those analysis methods has enabled to discover and quantify ultralow concentrations of toxic substances that earlier nobody even supposed to be present in food. Determination of tiny amounts of toxins has little sense without comparing the results with the toxicological characteristics of these substances such as LOAEL or acute lethal doses. Since often we have to do with human acute intoxications, the possible short analysis time is also an important parameter in selecting the most appropriate method(s).