农药毒性令人谈虎色变。有人因此断言化学农药很快会退出历史舞台。有人说“绿色食品”在生产过程中不能使用农药;还有文章讲农药是致癌的元凶。其实,这些说法并不科学。农药的大多数品种用于防治农业有害生物,它们一般对人体也有一定毒性。可以说农药的多数品种属于“毒物”。但是,毒性是相对的,毒物的危险性与它的剂量有关。这种毒性与剂量关系的例子在日常生活里人们经常接触的各类化学品中屡见不鲜。一包香烟的提取物一次性注射到体内足以杀死一匹马,但烟民们吞云吐雾仍乐此不疲;人在渴极之时喝海水往往致命,餐饮却离不开食盐;缺铁性贫血是人、畜常见病,过量摄入铁质即会中毒;维生素 A 为人体必需,大量服用则有生 Pesticide toxicity is talkative. Some people therefore assert that chemical pesticides will soon exit the stage of history. Some people say that “green food” can not be used in the production process of pesticides; there are articles that pesticides are the culprit cancer. In fact, these statements are not scientific. Most varieties of pesticides are used to control agricultural pests, and they generally have some toxicity to humans. It can be said that most varieties of pesticides are “poison”. However, toxicity is relative and the risk of poisoning is related to its dose. Examples of this relationship between dose and toxicity are common in the types of chemicals people are exposed to in daily life. A pack of cigarettes extract a one-time injection into the body enough to kill a horse, but smokers swallow puff is still happy; people are often thirsty to drink sea water is often fatal, but food can not be separated from salt; iron deficiency Anemia is human, animal common disease, excessive intake of iron that will be poisoning; vitamin A is essential for the body, taking a large number of students