因化学加工、人为添加及环境污染所导入食品中的有毒化合物容易被认识和预防;而许多以食品的天然组分形式存在的天然毒素,由于毒性大,且与食品混为一体,不容易被认识和确定,从而对健康威胁更大。作者将它们分为内因毒素和外因毒素,那些由食品原料自身产生并带进最终食品中的为天然内因毒素;由食品原料以外其它天然方式产生的且污染食品的或被食品蓄积的为天然外因毒素。 Due to chemical processing, artificial additives and environmental pollution into the food poisoning compounds easily recognized and prevented; and many natural toxins in the form of natural components of food, because of toxicity, and mixed with food, not easy to be Recognize and determine, and thus greater threat to health. The authors classify them into endo-toxins and exotoxins, which are native endotoxins that are produced by the food material itself and carried into the final product; natural exogenous toxins produced by other naturally occurring and food-contaminated foods or accumulated by the foodstuff toxin.