滴滴涕和六六六是两种常用而又很有(交力)的杀虫剂,它们可以杀死许多的医学昆虫,但是当我们到野外,特別是到森林地带,河漫滩地以及其他一些有野外吸血双翅昆虫孳生的地方去工作时,决不可能事先在短短的时间内,将该地的蚊虫等吸血昆虫全部消灭,那么为了防止这些害虫成羣地侵袭人体,妨害着人们的工作和休息,甚至于传染疾病,我们可以在身体裸露在外面的皮肤上擦上,或者将衣服涂浸一些蚊虫等吸血昆虫闻了就飞走的化学物质,这种能够将害虫赶走的化学物质叫做驱避剂(Repeilents)。人类在很早以前就知道用驱避剂来防止害虫的侵扰,比方我国古时曾经用“桂屑,苦楝叶屑,苦蒲以一升和一斗粉中,以粉身则辟蚊”(灵奇方),又如“蟾酥浸 DDT and HCH are two common and very effective insecticides that can kill many medical insects, but when we go wild, especially to forests, floodplains and other fields When working with blood-sucking, double-winged insects, it is impossible to destroy all the blood-sucking insects such as mosquitoes in a short time beforehand. In order to prevent these insect pests from invading the human body in groups, people’s work is hindered. Resting, or even contagious diseases, we can rub our bodies on the skin that is exposed to the outside, or we can apply chemicals such as mosquitoes and other blood-sucking insects to fly away. This chemical that can drive away pests is called Repellings (Repeilents). Humans knew from a long time ago that repellents were used to prevent pests from invading. For example, in ancient China, ”Lifoliate crumbs, bitter buckwheat leaf crumbs, and bitter buckwheat were used in one liter and one bucket of powder, while powder was used as a mosquito.“ ”(The spirit of the odd side), such as "