Pesticides in "pesticide science" there is a special chapter to tell, SLEEP COOL insect killer supplier although I am "human pharmacy" graduated, but the fate will have read a little pesticide science books, so since to talk about.

In addition, pesticide and pharmaceutical, veterinary medicine can be said to be a sister discipline, Chinese EASY ON Spray starch manufacturer many foreign companies are also a combination of pesticides and veterinary drugs, such as Novartis, Bayer, Takeda Pharmaceutical and so on. There are also some pesticide companies that do not have a strong pharmaceutical background, such as Mitsui Chemical in Japan, and I look at Jiangsu provinces.

There are many types of pesticides, Chinese EASY ON Spray starch supplier and the specific principles of each are different.

The answer below will be very long, the chemical basis can see all, no text can see the bold font can be.

There are four main ways that insecticides get into insects: touch, stomach poison, fumigation and ingestion. You can tell that from the name. Touch is directly from the skin into the insect; Stomach poison is to eat it; Fumigation is when the drug enters the insect's spiracles and kills it; Endorption is the most special - when a pesticide is absorbed by a plant and then enters the insect's body and kills the insect when it eats the plant.

Different types of pesticides have different effects, and many pesticides have only one or a few of the four effects mentioned above.

Four generations have passed since the invention of pesticides, and possibly a fifth.

First generation: inorganic pesticides, arsenic preparations, copper preparations (middle school chemistry books have Bordeaux liquid) (reminded that Bordeaux liquid is actually a fungicide) these and some core local methods of natural green plant pesticides;

The second generation: organophosphorus, organochlorine, carbamate, pyrethrin, the pursuit of broad spectrum, acute neurotoxicity, rapid killing of pests of synthetic pesticides;

Third generation: growth and development regulators, juvenile hormones such chronic effects, disturb the normal growth and development of insects deworming or insecticides;

Fourth generation: Pheromones, antifeedants, insecticides that directly regulate insect behavior and activity, act more slowly, but can significantly curb the next generation of insect populations;

Imagine the fifth generation: for example, the brain hormones that act on insects, the so-called insect "mind control agents," which don't kill insects, are just a defensive repellent.

At present, it is basically a mix of two, three and four generations of pesticides, mainly through the following kinds:

Organochlorine pesticides.

Organochlorine is divided into two categories, one is not allowed to use phenyl DDT (666), generally believed to pollute the environment, causing harm to humans and animals; The other category is newer non-phenyl pesticides, including toxaphene and endosulfan, currently the most widely used pesticide (Endosulfan is also now banned and arguably no new organochlorine pesticide varieties are available).

endosulfan

Organochlorine compounds are basically nerve agents that act on all parts of an insect's nervous system. DDT is an axon sodium channel agonist; When 666 acts on synapses, it can cause excessive release of acetylcholine from synapses, which causes insects to be in an abnormal state of excitement for a long time and eventually die.

Organophosphorus pesticides.

Organophosphorus is a large category of insecticides, and the well-known dichlorvos belongs to organophosphorus insecticides. Divided into the following categories:

Phosphate esters: such as domestic animals can eat gastrointestinal insect repellent naphthalene peptide phosphorus, but can not eat fast phosphorus;

Sulfur phosphate esters: less toxic than phosphate esters, and chemical stability, now used more widely and the most important, such as internal phosphorus absorption;

systox

As a reminder, the internal phosphorus structure is actually a mix of sulfur driven and sulfur driven. If you want to give an example of a typical sulfur-driven phosphate pesticide, parathion seems more appropriate:

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Dithiophosphate esters: the toxicity is even lower, and now the fastest growing class. For example, malathion, a low-toxicity insecticide, has no absorption effect and can only play toxicity in insects, and will be quickly hydrolyzed by phosphatase after entering the body of warm-blooded animals and lose some toxicity. At present, the ternary asymmetric organophosphate in dithiophosphate is a research focus in the field of asymmetric synthesis and pesticide science.

malathion

thiophosphate esters: In fact, dithiophosphate esters are activated by modification, not to mention;

Phosphoramidic acid derivatives: the famous methamidophos is this;

Meflophosphate: Meflophosphate seems to use their own choice now;

pyrophosphate derivatives: capsicum-flavored octadecaphosphate belongs to this category;

Phosphonate (see clearly not phosphate, is phosphonate) : trichlorphon is this;

trichlorphon

Phosphonate esters: This should be only one kind of chlorophosphine.

The toxicity mechanism of organophosphorus pesticides is more complex than that of organochlorine, after all, there are many kinds.

But we're basically interfering with the nervous system and inhibiting the action of cholinesterase. So once inside the insect, the nervous system will continue to be abnormally excited, overstimulated, and eventually die. But these unfortunately, the human nerve conduction mechanism is also similar to insects, so there are problems many companies early organophosphorus pesticides also have greater harm to human and animal health, acute organophosphorus poisoning (AOPP). Therefore, one of the main research and development directions of organophosphorus pesticides in the field of pesticide science is to study organophosphorus pesticides that can be rapidly metabolized by the human body to reduce their toxicity to humans and animals.