Chemicals are agents that are used to destroy insect pests, weeds, some types of fungus, etc. They are most often used in agriculture. Agricultural pesticides are also called pesticides. in a broad sense, pesticides are agents designed to destroy potential pests that pose a danger to a person or his property. Depending on who the pesticides are directed against, they are divided into several groups. For example, insecticides are designed to combat insect pests, acaricides - against mites, rhodonticides - against rodents, herbicides - against weeds, fungicides - against fungi, bactericides - against bacteria, zoocides - against potentially harmful warm-blooded animals, nematicides - against roundworms and t. In addition, all pesticides are divided into systemic and contact. Means belonging to the first group penetrate into plants and kill pests that devour them. Toxic chemicals of the second group destroy animals or plants by direct contact. And, finally, there are three groups of danger of pesticides for humans, as well as several of their types, depending on what kind of chemicals were used in the manufacture of the product. In particular, pesticides are organochlorine, organophosphate, organic mercury, mouse yaks, etc. Despite the fact that pesticides are designed to protect people and domestic animals from insects that are carriers of infection, and plants, wood, food supplies, etc. - from potential pests, they themselves can be very dangerous. Gradually accumulating in plants, soil, water, etc., they begin to poison even those people and animals that have not been in direct contact with them. The use of some pesticides also leads to a deterioration in the ecology and quality of food, disruption of some natural processes, etc. The situation is complicated by the fact that some pests develop immunity to such agents. It was for these reasons that the use of some of the strongest pesticides, in particular, DDT, was strictly prohibited.
First of all, pesticides are divided according to their chemical structure into organic and inorganic.
Organic pesticides are divided into:
According to the method of action on a living organism, as well as the mechanism of penetration, they are divided into:
Like any chemical, pesticides have varying degrees of hazard. The WHO classification for pesticides distinguishes four degrees of hazard of their exposure, which can be presented in the form of a table:
Hazard level Oral ingestion Skin contactSolid liquidsSolid liquids very hazardous substances5 or less20 or less10 or less40 or less hazardous substances5-5020-20010-10040-400 moderately hazardous50-500200-2000100-1000400-4000lowly hazardous500 and more2000 and more1000 or more4000 p>
Note. Chemical pesticides are the main sources of environmental pollution. Their use is mandatory for agriculture, healthcare and industry.
In order to prevent more harm from pollution, you need to pick them at the least danger to humanity: