Chemical formula of dust. What is dust from bedbugs, its effective use, advantages and disadvantages

Dichlorodiphenyltrichloroethane, better known by the abbreviation DDT, was synthesized as early as 1874, but it was not until 1937 that the compound was discovered to be highly toxic to insects.

The first case of widespread use of a new insecticide was a massive DDT dusting of the Pacific Islands, undertaken American army before the liberation of the islands from the Japanese in 1942. These paratroopers were protected from malaria, dengue fever and other tropical diseases carried by insects. In the winter of 1944, American soldiers in Naples were dusted with dust to kill the lice.

After World War II, a new insecticide began to be widely used to kill pests. Agriculture, but after some time it turned out that this substance decomposes in nature extremely slowly, is transferred to other organisms through the food chain, accumulates in them and slowly poisons them. In addition, insect lines resistant to DDT have appeared that can withstand even tenfold doses of the drug. Therefore, for almost thirty years, the use of DDT has been banned in most countries (the first was Sweden, which banned this insecticide in 1969). True, the World Health Organization has not banned DDT, but it has not been financing its purchases by developing countries for a long time. The World Bank does not even give loans to countries that still use this insecticide.

However, it now appears that no the best remedy to control malarial mosquitoes than DDT. When the insecticide was banned in South Africa, far behind other countries, in 1996, the incidence of malaria increased by more than six times, and five years later it was again allowed. Just don't spray tons of it from planes flying over cities, ponds, swamps and agricultural land. Careful use inside dwellings, experts now believe, is quite acceptable. According to WHO, two grams of DDT per square meter adobe walls reduce the likelihood of malaria infection of the tenants of the house by 90%. Spraying should be repeated only once a year. Therefore, the World Health Organization approved the use of DDT for indoor spraying, pointing out that it is not only the best weapon against malarial mosquitoes, but also the cheapest and most effective of insecticides. If used correctly, DDT does not pose a threat to nature or humans.

In addition, data on the accumulation of DDT and toxic products of its decay in wildlife have recently been called into question.

About twenty years ago, ecologists monitoring the content of toxic substances in the fat of marine mammals began to discover unknown substances in fat samples. organic compounds with chlorine atoms in the molecule. In structure, they resembled DDT, and it was concluded that the drug and its decomposition products are carried by rivers to the ocean, and there they accumulate in mammals.

And just recently, in a vial of whale oil, preserved in the last whaler sailboat, put on eternal joke off the coast of Connecticut (USA), the same compounds were found - as many as 11 of their varieties. Since the fat sample dates back to 1921, when DDT was not produced or used, it remains to be concluded that these compounds are synthesized somewhere in the ocean. Where exactly - is still unclear, it is only known that something like DDT is produced by symbiotic bacteria living in sea sponges and, apparently, protecting their hosts from being eaten by this.

For each type of processing, certain pesticides are used:

• herbicides fight weeds.
• Insecticides kill harmful insects.
• Fungicides- Save plants from fungal diseases.
• Zoocides- poison rodents.

Note. A number of these poisons include blockers of reproduction and growth of organisms.

Pesticides stop biological processes in harmful organisms:

• bacteria.
• weeds.
• Insects.

They are mainly used:

• In the field.
• processing industry.
• Forestry.

Note. Their benefits are undeniable. A side effect of the application can be considered the harm that they cause to nature - birds, animals, humans.

This is:

• Chlorine-containing.
• Phosphorus-containing.
• With metal content.
• Alkaloids (with nitrogen).

Note. Nitrogen-containing pesticides are especially hazardous to human health.

Symptoms of poisoning are poorly identified, and therefore it is difficult to diagnose it with this substance:

• Pesticides fight insects, field rodents, weeds.
• They do not cause direct harm to a person, but when they enter the body with food and water, they accumulate there and poison the organs of the digestive tract.

Injury can occur during direct contact with the substance through the skin or inhalation.

Insecticide DDT

Pesticides DDT is a compound that slowly degrades and accumulates in the natural environment

After completing its useful mission, DDT has a toxic effect on water, soil, and plants:

• It has the ability to be transmitted through the food chain and penetrate into living organisms. This pesticide exhibits mutating properties, is a carcinogen and poses a threat to all living things. But during the years of its use there were no incephalitis mites.
• DDT accumulates in the fat cells of the liver and kidneys, the main human cleansing organs.

Note. But, despite the danger, many countries of Central Asia use dust in the processing of cotton fields.

Dust was used not only to fight insects, but also in the treatment of malaria and typhoid:

• But it negatively affects the ability to reproduce in living beings. Scientists noticed this on the example of birds that settled on treated water bodies.
• It accumulates in tissue cells and is not removed by purification systems.

Note. For the use of dust is prohibited in many countries of the world.

Aldrin

Dieldrin

Characteristics of DDT

If you miss the moment, you can lose half the crop in the field and in storage.

When is DDT pesticide used?

• Against flying insects - carriers of malaria.
• In the fight against pests of industrial and food crops - cotton, flax, soybeans, peanuts.
• Powerful locust control.

Dust (DDT) is a white crystalline substance that is ground for use into a dusty powder.

The history of the drug

DDT pesticide decoding: dichlorodiphenyltrichloroethane (DDT) is an insecticide obtained in 1874 by the German chemist Otmar Zeidler.

This connection did not find for a long time practical application until Swiss scientist Paul Miller discovered its insecticidal potential in 1939 and used it against malarial mosquitoes. For this great scientific research, he received Nobel Prize in medicine in 1948.

Description of the drug

DDT is a simple, effective, inexpensive pest control agent. It is obtained by the synthesis of chlorobenzene and sulfuric acid.

Note. Signs of poisoning are dizziness, vomiting, inflammation of the mucous membranes, redness of the eyes, weakness.

• Particular care must be taken when handling the chemical during seed treatment, when poisonous dust is in the air. It is necessary to use respirators, protective clothing.

The intensity of poisoning is determined according to the table as a result of experimental studies:

Benefits of DDT

• Effectively fights domestic insects - flies, cockroaches, moths.
• It is used to destroy pests of garden crops - the Colorado potato beetle and aphids.

Protects crops of many crops from insect pests in agriculture.

Exploits of DDT in the name of humanity

Typhus epidemic in Naples in 1944. More than a million people were sprayed with a solution of dust, which led to the destruction of lice - carriers of typhus. The disease has receded. They successfully fought typhus with the help of dust in many other hot countries.

DDT significantly increased crop yields:

• Fast results, low cost simple technology production increased the use of DDT.
• Insufficient research has led to its widespread and uncontrolled use.

An effective preparation was used both in industrial volumes and in the household. This led to the pollution of water bodies, soils, vegetation, negative influence on the human body.

Instructions for using dust at home

It is able to remove fleas, bedbugs and cockroaches from the living quarters.

Applying dust competently and carefully, you can avoid skin damage and poisoning. For more detailed information about the properties of the drug, we recommend watching the video in this article.

Click on photo to enlarge

DDT- the chemical active substance of pesticides, an insecticide from the class of organochlorine compounds, was previously used (including in mixtures with other active components) in agriculture to control harmful insects and pests of stocks, as well as to control insect vectors of human diseases. Currently absent from the lists of pesticides allowed for use.

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Physicochemical characteristics

White crystalline substance. DDT is sparingly soluble in water, soluble in many organic solvents, best in the ethers of the lower fatty acids, ketones, aromatic hydrocarbons and halogen derivatives of aliphatic and aromatic hydrocarbons.

The technical preparation is a complex mixture of compounds, the content of the 4,4'-isomer in it reaches 75-76%. It looks like scales or small pieces of white, gray or slightly brownish color. It has a clearly perceptible smell, which is also characteristic of preparations made from DDT.

Scheme for the synthesis of DDT analogs

DDT analogues

Among the synthesized and studied compounds, asymmetric analogues of DDT are of considerable interest. Getting them presents certain difficulties; synthesis can be carried out according to the following scheme: (image).

The process of biodegradation of DDT analogues in artificial ecosystem proceeds in different directions compared to DDT. If with the main products are hydrophobic compounds, then with biodegradable analogues these are hydrophilic substances that are easily excreted from the body of mammals and do not accumulate in adipose tissue.

DDT analogues

DDT analogues

1) 1-chloro-4-ethyl)benzene;

2) 1-methoxy-4-benzene;

3) 1-ethoxy-4-benzene;

4) 1-methyl-4-benzene

5) methyl(4-phenyl)sulfane 6. 1-ethoxy-4-benzene

The following analogues have found practical application:

Methoxychlor

White crystalline solid, m.p. 89°C. Technical product melts at 70-85°C. Usually for practical use produced a recrystallized preparation. It dissolves well in organic solvents, including ketones and aromatic hydrocarbons.

Methoxychlor is similar in chemical properties to DDT, but its dehydrochlorination proceeds much more slowly.

For experimental animals 50 substances ~ 6000 mg/kg.

Under the action of soil microorganisms, methoxychlor decomposes to the simplest substances.

DDD

First product of reductive DDT.

• Melting point 112 °C,
• 50 3400 mg/kg.

Previously used as an insecticide.

pertan

• Melting point 56-57°C.
• 50 for mice - 6600 mg / kg.

The insecticidal activity of this compound is much less than that of methoxychlor and DDT. Has received some use in the US.

DFDT

analogue of DDT.

• Boiling point 138-140 °C at 27 Pa,
• Melting point 45°C.

The substance is practically insoluble in water, soluble in organic solvents. DL 50 for experimental animals 480 mg/kg. DPDT is significantly lower than DDT, but its cost is much higher, as a result of which it has not found significant application.

Many other similar compounds have been synthesized, but they have not received practical significance. (image).

Action on harmful organisms

. After long-term use of DDT, insects can acquire resistance to it, as well as to other organochlorines at the same time. In many areas of the former USSR, houseflies have become resistant to DDT; stable populations of the potato beetle have been noted.

The natural resistance of ticks to this is swollen.

Toxicological data
(mg/kg human body weight)	0.005/0.0025 (for children)
in soil (mg/kg)	0,1 ()
in the water of reservoirs (mg / dm 3)	0,1
in the air working area(mg / m 3)	0,001 ()
in atmospheric air(mg / m 3)	0,001 ()
in products (mg/kg):
in melons	0,1
in grapes	0,1
in mustard	0,1
	0,1
in gelatin	0,1
in animal fat	1,0
in fish oil	0,2
in cereal grains	0,02
in legumes	0,05
	2,0
in cocoa beans	0,15
in cocoa products	0,15
in potatoes	0,1
in sausage	0,1
in canned meat and poultry - by raw material (in terms of fat)	0,1
in canned fruits and berries, vegetables - for raw materials	0,005
in milk and whey protein concentrates	1,0
in starch and potato molasses	0,1
in starch and molasses from corn	0,05
in cereals - by raw material	0,15
in corn	0,02
in culinary products	0,1
in flax (seeds)	0,1
in vegetable oil	0,1
in vegetable oil of the highest degree of purification	0,1
in deodorized vegetable oil	0,1
in non-deodorized vegetable oil	0,2
in butter	0,2
	0,005
in milk and dairy products	0,05
in milk and dry dairy products (in terms of fat)	1,0
	0,15
in flour confectionery	0,02
in meat and poultry (fresh, chilled and frozen)	0,1
in the meat of marine animals	0,2
	0,1
in cucumbers	0,15
in the liver of fish and products from it	3,0
in protein products from seeds of cereals, legumes, and other crops	0,01
in products baby food: adapted milk formulas (for children 0-3 months of age)	0,01
in baby food: products for children 4-12 months. age: cereals, vegetables	0,01
in milk processing products (cheese, cottage cheese products, butter, cream, sour cream)	1,0
in rapeseed (grain)	0,1
in sea fish, tuna (fresh, chilled, frozen)	0,2
in freshwater fish (fresh, chilled, frozen)	0,3
in salted, smoked, dried fish	0,4
in canned fish (freshwater, marine, tuna fish, meat of marine animals) - for raw materials	3,0
in oily herring	2,0
in sunflower seeds, peanuts	0,15
in soy (beans)	0,05
in juices - by raw material	0,005
in by-products (liver, kidneys)	0,1
	0,7
in fruit	0,1
	0,1
	0,1

Application

Previously, DDT was used to control various insects - plants and vectors of animal and human infections. Its serious drawback was the lack of an acaricidal effect on herbivorous mites, so it was necessary to treat a number of crops with DDT together with.

Previously, DDT was produced in the form of many drugs:

DDT used to be one of the most important pesticides for the control of most leaf-eating insects: beetles, caterpillars, flies, etc. in almost all cultures. With great restrictions, it is used to control insects and ticks in veterinary medicine. It is more effective against caterpillars than hexachloran, but it is much less effective against locusts, wireworms (Clickworms) and some others.

tank mixes

. Often, DDT was used in a mixture with hexachlorane: hexachloran acts faster on many than DDT, but the latter remains on the leaves for a longer time.

Toxicological properties and characteristics

DDT is resistant to degradation. Neither light, nor enzymes, nor critical temperatures can greatly affect the process of DDT decomposition. As a result, when released into the environment, DDT enters the food chain. In them, the toxicant accumulates in significant quantities: first in plants, then in animal organisms and, as a result, in human body. Researchers' calculations showed that at each link in the food chain, there is a tenfold increase in the content of DDT:

• Sludge containing DDT - 1x
• Plants (algae) - 10x
• Small organisms (crustaceans) - 100x
• Pisces - 1000x
• Predatory fish - 10000x

Low water solubility and high fat solubility cause DDT retention

in fat cells. The rate of accumulation of a substance in the body varies depending on the concentration, duration of exposure, type of living object and environmental conditions. The high degree of retention of DDT indicates that toxic effects can manifest themselves over a long period of time, as well as at a considerable geographical distance from the place of exposure. Organisms with high nutritional levels tend to accumulate more DDT than organisms with lower nutritional levels. In the organisms of migratory animals, DDT is able to be transported around the world, as well as by air and ocean currents.

in the soil

Under normal conditions, DDT can remain in the soil for up to 12 years; under anaerobic conditions, it is decomposed by microorganisms for 2-4 weeks. The rate of decomposition is influenced by temperature: the higher it is, the faster the decomposition takes place. The decomposition of DDT under anaerobic and aerobic conditions proceeds by various mechanisms.

Human impact

Active substance has an acute toxic effect on humans. In small doses, it can cause poisoning (in adults, most often without negative consequences), in large ones it can cause death. DDT can enter the bloodstream, accumulate in the adipose tissue of the body, and enter the mother's milk. Theoretically, due to long-term exposure to DDT or during weight loss, its accumulation in the body can lead to intoxication. Objectively, the consequences of the accumulation of the toxicant in the human body have not been established. DDT has no mutagenic (resulting in a permanent change in living matter), carcinogenic (causing cancer), embryotoxic (provoking changes in the fetus), teratogenic (becoming the cause of deformities) effects, does not lead to a decrease in fertility (the ability to have offspring). The substance leads to the induction of microsomal enzymes, but does not cause any morphological changes in the liver, and the enzymatic activity as a whole does not exceed the norm. On the immune system In humans, exposure to DDT is likely to have an inhibitory character (inhibits the activity of enzymes, in this case inhibition of the formation of antibodies), but this has not been definitively established.

Impact on other living organisms

Indicators for both chronic and acute various kinds invertebrates are not the same. For aquatic invertebrates, DDT is high at acute exposure at concentrations as low as 0.3 µg/l. At the same time, toxic effects include reproductive and developmental disorders, changes in the cardiovascular system.

Aquatic microorganisms are more sensitive to the action of DDT than terrestrial ones. At a concentration in environment 0.1 µg/l DDT is able to inhibit photosynthesis and the growth of green algae.

Earthworms are not susceptible to the acute toxic effects of DDT at levels that are likely to exceed those found in environmental conditions.

DDT has an adverse effect on the reproductive function of birds, causing thinning of the egg shell (and, as a result, its destruction and death of the embryos).

Some mammals, particularly bats, may also be adversely affected by the toxicant. Animals caught in the wild, in which a residual content of DDT was found in their adipose tissue, died as a result of artificial starvation, which served as a model for fat loss during migratory flights.

Table Toxicological data drawn up in accordance with GN 1.2.2701-10.

Symptoms

In case of contact with the eyes, intense pain occurs, severe conjunctivitis. Upon contact with the skin, a local irritating effect is manifested.

The clinical picture of chronic: headaches, dizziness, insomnia, loss of appetite, rapid mental and physical fatigue, irritability. In the future, convulsive pains in the limbs, especially along the nerve trunks, trembling of the arms and legs, emotional instability (unreasonable crying), increased sweating, shortness of breath, palpitations, pain in the heart and right hypochondrium, polyneuritis with tingling and pinching of the fingers and toes , perverted skin sensitivity, numbness in the area of ​​the hands and forearm. There may be changes in speech and vision. chronic poisoning accompanied by hepatitis, gastritis, bronchitis and functional changes in the kidneys (protein and erythrocytes in the urine, granular cylinders), signs of eczema and pyoderma form on the skin. On the part of the blood, leukocytosis, accelerated ESR are observed.

Story

DDT was first synthesized in 1873 by the Austrian chemist Otmar Zeidler. Substance long time did not find application until, in 1939, the Swiss chemist P. Müller revealed its insecticidal properties. In 1942, the drug went on sale and began its march around the planet. It proved to be an ideal tool for the control of vectors of typhus and malaria - diseases that were the biggest medical problems during the Second World War. DDT for humans seemed so low that it was supposed to be sprayed on the body to prevent typhus. The relatively low price of DDT allowed it to be used to spray entire islands. Pacific Ocean before the landing of the US armed forces to destroy mosquitoes there and protect the army from malaria. (a photo) The high stability of the drug, even with a single spray, ensured its effective action for several months. In 1948 Muller was awarded the Nobel Prize in Physiology or Medicine.

AT former USSR DDT production began in 1946 in Moscow and the Chuvash city of Vurnary. In the 50-60s, it was used in an amount of more than 20 thousand tons per year. As a result, a significant part of the territory turned out to be contaminated, and dust in dangerous doses also got into food. These shortcomings reduced the attractiveness of DDT as a drug, and in the 1970s very strict restrictions were placed on its production and use.

The most significant "merits" of the use of DDT on a global scale are:

The world quickly gained positive experience with the use of DDT, which led to the widespread production and use of the drug. But wide use also led to the formation in the minds of people of erroneous ideas about the non-toxicity of DDT, to the cultivation of carelessness in the use of the drug and non-compliance with safety standards. The current situation could not but lead to negative consequences, including fatal ones.

DDT has conquered the whole world, because, by destroying agricultural plants, it contributed to the increase in yield. But its stability (which alerted Muller himself) and a wide range of insects on which it had a detrimental effect, fraught with danger: the drug did not decompose into harmless components, but accumulated in soil, water and living organisms, destroying not only harmful, but also beneficial ones. insects, caused poisoning and death of other animals to which it was transmitted through food chains. Due to the harmful effects of DDT use and the damage it caused to the environment, the widespread use of this powerful drug was banned in the United States in 1972. By the end of the 1970s, most developed countries had limited or completely banned the use of DDT on their territory. In the USSR, its use was also officially banned in the 70s of the XX century.

DDT in culture

Although the widespread and uncontrolled use of DDT has long been a thing of the past, both the current generation and our descendants, many years after today, will experience the consequences of the "insecticide frenzy" of the 1940-1970s, after which this substance and its derivatives in the amount of many thousand tons remained in the soil, water of rivers and seas, snow cover, living organisms.

Organochlorine compounds left their mark not only in material objects, but also in culture, for example, in some literary opuses. There is such a creative category as chemical fairy tales, in the plot of which it is customary to assign a place to some element or substance. If you take anything from the time before the introduction of sanctions on the production of DDT, then you can see a very positive attitude towards this substance. For example, there is one old fairy tale - unfortunately, its author has been forgotten over the years - which tells about a wizard who was very fond of cooking cabbage soup, which he grew in his garden. One day, caterpillars began to encroach on his crop. Not a single spell helped to get rid of them, and the wizard was already completely desperate, but then one smart boy advised him to use dust. The magician tried and made sure that dust was better than any spells, he saved his cabbage and for a long time remembered the good boy, thanks to whom he got such a tasty, thick, rich soup ...

At one time, a positive attitude towards DDT even penetrated into the everyday speech of Soviet citizens. For example, for a long time it was customary to use the expression “To drag like a boa constrictor (worm) over a pack of dust”, which meant “to experience pleasure from something”. This phrase is used to this day, but it has already been superseded by more modern expressions. Along with this, the word “dust” in some regions of the country is used as a variant of a censored curse, which can be used to express surging emotions if the situation does not allow the use of a stronger and more familiar word.

In the minds of many, the word "DDT" is associated with a famous Russian rock band, which, thanks to its 30-year existence and undying popularity, is known to all lovers of real music in a wide age category from about 15 to 50 years old.

Why the group was named that way, knows, probably, only the leader of the group Yuri Shevchuk, the only remaining member of the original composition. According to one version, the name was chosen by chance, other sources claim that DDT in this case means just “ Orphanage creativity." Still others talk about a magnetic album called “Dust”, unknown to the public, which was released the very first and gave the band its name. Be that as it may, DDT does not have a single song about the famous poison, and no matter what led the creators, the idea about the name turned out to be successful: associative, without pathos, and most importantly, short.

In addition to the cases listed, dichlorarely appears anywhere. Although he caused significant harm to the environment, in comparison with some of his "relatives", he left a less noticeable mark on world culture. But, for example, dioxin, which is also an organochlorine compound, is much more "famous". The famous historical episode with the use of dioxins during the Vietnam War turned into thousands of victims and left a much richer cultural heritage. He appears in over 300 works of art, countless songs and poems are dedicated to him, even from Russian authors. Probably everyone knows the song of the group "Chizh and Co" called "Phantom", which begins with the line: "I'm running on scorched earth ..." This is the story of an American soldier who ended up on enemy lands after his plane was shot down during a mission , and the scorched earth mentioned is the result of the so-called "Agent Orange" in the jungles of Vietnam.

Fortunately, DDT is much smaller than dioxins, so nothing can be said about it in such a context. Now, due to the ban in most countries, the “popularity” of this substance and the frequency of mentioning it in the media is gradually decreasing. Accordingly, it is gradually being ousted from all areas of world culture. However, no, no, and alarming information pops up: either another large storage of old stocks of the drug was found somewhere, or its presence in dangerous quantities was found in milk. Despite the fact that they have already begun to forget about the no, he himself has not gone away, and his remains continue to poison the environment. So it is unlikely that memories of DDT can be left in the past in the near future: we will hear about it again, and more than once.

And many other countries. However, recently there have been a number of reports on the significantly exaggerated harm of DDT. There is an assumption that the main harm to mammals and birds is caused not by DDT itself, but by impurities (mainly dioxins) that occur when it is used. industrial production. WHO officially recommends the use of DDT for the prevention of malaria.

History of creation, obtaining, application

DDT (C 14 H 9 Cl 5) is a classic example of an insecticide. In form, DDT is a white crystalline substance, tasteless and almost odorless. First synthesized in 1873 by the Austrian chemist Othmar Zeidler, it was not used for a long time until the Swiss chemist Paul Müller discovered its insecticidal properties in 1939, for which he received the Nobel Prize in Medicine. in 1948 as "For the discovery of the high efficacy of DDT as a contact poison".

DDT is an extremely effective and very easy to obtain insecticide. It is obtained by the condensation of chlorobenzene (C 6 H 5 Cl) with chloral (Cl 3 CCHO) in concentrated sulfuric acid (H 2 SO 4). DDT is an externally acting insecticide, that is, it causes death on external contact, affecting nervous system insect. The degree of its toxicity can be judged by the fact that fly larvae die when less than one millionth of a milligram gets on the surface of their bodies. Thus, it can be argued that DDT is highly toxic to insects, while at appropriate concentrations it is harmless to warm-blooded animals. However, if exceeded, it also has a toxic effect. In particular, in humans, into whose body DDT can penetrate through the respiratory system, skin, gastrointestinal tract, it causes poisoning, the signs of which are general weakness, dizziness, nausea, irritation of the mucous membranes of the eyes and respiratory tract. DDT poisoning is especially dangerous during the treatment of premises and seed. In addition, exposure to the body in large doses can lead to death. The data obtained as a result of clinical studies make it possible to determine the toxicity of DDT for humans as follows: see Table No. 1. Due to the danger of DDT poisoning, all types of work with it are carried out with the obligatory use of means personal protection(overalls, footwear, respirator, gas mask, goggles, etc.).

The benefits and harms of DDT

In addition to domestic use as a pest control agent such as flies, cockroaches and moths, as well as agricultural benefits as a pest control agent such as the Colorado potato beetle and aphids, DDT has a number of universally recognized "heroic" merits on a global scale, among them the most significant are the following:

• In January 1944, a typhoid epidemic in Naples was averted with DDT. This is the first winter epidemic of louse-borne typhus that has been stopped.
• In India, thanks to DDT, not a single person died from malaria in 1965, while 3 million people died in 1965. The US National Academy of Sciences estimates that DDT saved 500 million lives from malaria during its use through 1970 .
• In Greece in 1938 there were a million malaria patients, but in 1959 there were only 1,200.
• In the Italian province of Lazia in 1945, the death rate from malaria per month was 65-70 people, and after they began to use DDT, it dropped to 1-2 people in 1946.
• The use of DDT largely freed India of visceral leishmaniasis (vectored by Mosquitoes) in the 1950s and 1960s.

Thus, the world quickly gained positive experience with DDT. This experience has led to a rapid increase in the production and use of DDT. The growth in the production and use of DDT was not the only consequence of the "good practice". It also caused the formation in the minds of people of erroneous ideas about the non-toxicity of DDT, which in turn led to the cultivation of carelessness in the use of DDT and a disregard for safety standards. DDT was used everywhere and everywhere without complying with the requirements established by sanitary and epidemiological standards. The current situation could not but lead to negative consequences. For example,

• in kindergarten, in Iran, when preparing porridge, having mixed up the cans, instead of powdered milk, the corresponding amount of DDT dust was poured into the boiler. Died, poisoned, several dozen;
• In the early 1950s, the Colombian government forcibly sprayed peasants with DDT at their Ministry of Agriculture appointments to control head lice.

The peak of this euphoria came in 1962, when 80 million kilograms of DDT were used for their intended purpose in the world and 82 million kilograms were produced. After that, the volumes of production and use of DDT began to fall. The reason for this was the worldwide discussion about the dangers of DDT, which was due to the book of the American scientist Rachel Carson (Rachel Carson) "Silent Spring" ("Silent Spring", which means "Silent Spring" or "Silent Spring"), in which Carson argued that the use of DDT had a detrimental effect on reproductive function in birds. Carson's book caused a wide resonance in the United States. Various environmental organizations have taken Carson's side, such as the Environmental Defense Fund, the National Wildlife Federation. On the side of Carson's opponents, DDT manufacturers and the state administration supporting them, represented by the Environmental Protection Agency, stood up. The debate about the dangers of DDT soon escalated from national to international. However, Carson's conclusions about the dangers of DDT had no scientific basis.

In his book, Carson draws on the research of James DeWitt, summarized in his papers "Effects of Chlorinated Hydrocarbon Insecticides upon Quail and Pheasants" and "Chronic Toxicity to Quails and Pheasants of Certain Chloric Insecticides". insecticides” (“Chronic Toxicity to Quail and Pheasants of Some Chlorinated Insecticides”). Carson praises DeWitt's research, calling his experiments on quails and pheasants classic, but in doing so she misrepresents the data that DeWitt obtained in the course of his research. Thus, referring to DeWitt, Carson writes that "Dr. DeWitt's experiments (on quails and pheasants) established the fact that exposure to DDT, without causing any noticeable harm to birds, can seriously affect reproduction. Quails fed diets with DDT survived throughout the breeding season and even produced a normal number of eggs with live embryos. But few chicks hatched from these eggs. However, Carson omits numbers in his book. The fact is that from the eggs of quails that ate food containing DDT in large quantities, namely 200 ppm (that is, 0.02%; for example, at that time the maximum permissible concentration of DDT for eggs established in the USSR was 0.1 ppm), only 80% of chicks hatched, however, from the eggs of quails of the control group, whose food was free of DDT, 83.9% hatched. Thus, the difference between the quails fed with DDT and the control group was only 3.9%, which made it impossible to draw a conclusion regarding the effect of DDT on reproductive function in birds. Much later, it was found that DDT causes thinning of the egg shell and death of the embryos. However, different groups of birds vary greatly in their sensitivity to DDT; birds of prey are most sensitive, and under natural conditions a pronounced thinning of the shell can often be found, while chicken eggs are relatively insensitive. Due to omissions made by Carson in her book, most experimental studies has been delivered with DDT-insensitive species (such as quail), which often showed little or no shell thinning. Thus, Carson's book misdirected science by targeting birds that were not sensitive to DDT, thereby delaying research into DDT exposure in birds by 20 years. However, now we can talk about the impact of DDT on the environment from a scientific standpoint.

Degradation resistance

DDT is highly resistant to decomposition: neither critical temperatures, nor enzymes involved in the neutralization of foreign substances, nor light are able to have any noticeable effect on the process of DDT decomposition. As a result, when released into the environment, DDT somehow ends up in the food chain. Turning in it, DDT accumulates in significant quantities, first in plants, then in animals and, finally, in the human body. The calculation of Damen and Hayes (1973) showed that at each link in the food chain there is an increase in the content of DDT by a factor of 10:

Plants (algae) - 10x

Small organisms (crustaceans) - 100x

Pisces - 1000x

Predatory fish - 10000x

This rapid accumulation of DDT is clearly seen in the following example. So, in the study of one ecosystem in Lake Michigan, the following accumulation of DDT in food chains was found: in the bottom silt of the lake - 0.014 mg / kg, in crustaceans that feed on the bottom - 0.41 mg / kg, in various fish - 3-6 mg /kg, in the adipose tissue of gulls feeding on this fish - over 200 mg / kg.

The impact of DDT on humans

The available data on the effects of toxic effects of DDT on humans can be summarized as follows. DDT has an acute toxic effect on humans: in small and medium doses it causes poisoning, in adults for the most part without negative consequences in the future, in large doses it can cause death. DDT accumulates in the fatty tissues of the body, enters the mother's milk, and can enter the bloodstream. Theoretically, during weight loss, or due to long-term exposure, the accumulation of DDT in the body can lead to intoxication of the body. Objectively, the consequences of DDT accumulation in the human body have not been established. The impact of DDT does not have a carcinogenic (causing cancer), mutagenic (causing a permanent change in living matter), teratogenic (causing deformity), embryotoxic (causing changes in the fetus) effect on the human body, does not lead to a decrease in fertility (the ability to have offspring). DDT leads to the induction of microsomal enzymes, but does not entail any morphological changes in the liver, and enzymatic activity generally does not exceed the norm. The effect of DDT on the human immune system, apparently, is inhibitory in nature (it inhibits the activity of enzymes, in this case inhibition of the formation of antibodies), but this has not been definitively established.

It should be noted that many popular science sources contain categorical statements about the carcinogenic, mutagenic, embryotoxic, neurotoxic, immunotoxic effects of DDT on the human body. Thus, for example, it is alleged that DDT causes or contributes to the development of a variety of human diseases that were not previously considered to be associated with any chemical. These include cardiovascular disease, cancer, SARS, retrorental fibroplasia, poliomyelitis, hepatitis, and "neuropsychic manifestations". At the time these claims were made, the causes of all of these diseases without exception were unknown, or at least unproven. Needless to say, the DDT charge of predisposing to polio was dropped after the disease was brought under control through vaccination. Unfortunately, today there is no immediate possibility of combating cardiovascular diseases, cancer and many other less common human pathological conditions, the occurrence of which was attributed to DDT. Meanwhile, such irresponsible statements can bring great harm and, if taken seriously, may even interfere with the scientific search for the true causes and real measures to prevent these conditions.

The impact of DDT on other living organisms (except humans)

Available data on the effects of toxic effects of DDT on other living organisms can be summarized as follows. Aquatic microorganisms are more sensitive to the action of DDT than terrestrial ones. At an environmental concentration of 0.1 µg/l, DDT is able to inhibit the growth and photosynthesis of green algae.

Indicators of both acute and chronic toxicity for different types of aquatic invertebrates of DDT are not the same. In general, DDT exhibits high acute toxicity to aquatic invertebrates at concentrations as low as 0.3 µg/L, with toxic effects including reproductive and developmental disorders, cardiovascular changes, and neurological changes.

DDT is highly toxic to fish: LC50 values ​​(96 h) obtained in static tests range from 1.5 µg/l (largemouth bass) to 56 µg/l (guppies). Residual levels of DDT above 2.4 mg/kg of winter flounder roe caused abnormal development of embryos; with similar residual concentrations, as was found, the death of fry of lake trout in natural conditions is associated. The main target of the toxic action of DDT may be cellular respiration.

Earthworms are insensitive to the acute toxic effects of DDT at levels in excess of those likely to occur under environmental conditions.

DDT can have an adverse effect on the reproductive function of birds, causing thinning of the egg shell (which leads to their destruction) and the death of embryos.

DUST is so poisonous (and what a stink from it!), That it was discontinued a long time ago.

But my late grandmother had great respect for this drug and long years kept unmeasured reserves of DUST, used it with success: poison Colorado beetles in the garden, chasing lice for chickens, fleas for dogs ... I feel that this did not add health to my grandmother, as well as to all her household members (.

DDT or in the people dust used as an insecticide. In the twentieth century, it was especially common throughout the USSR, but it turned out that this drug is very very harmful to both people and plants. And the places where this drug was used suffered very significantly - for example, the spraying of vast areas of crops - these lands are still dangerous. And what can we say about the use of this drug in domestic conditions - this is generally nonsense. Now this drug is not available.

In fact, DUST is a powder, dust. This is chemical drug and is used to kill various harmful insects. In the last century, it was widely used as an insecticide. It was opened in 1939. It was forbidden to use it first in Europe, and then in Russia, because. it is very hazardous to health. And it affects the environment even in small doses. It does not collapse for decades and poisons all objects. It circulates in the sequence: soil - water - bottom sediments - fish.

Oh, I definitely remember this dust. My grandmother also adored him. She only chased them in front of people (that is, her children, but Mom didn’t allow us grandchildren) and poisoned cockroaches with rodents throughout the household plot. We were forced to deliver it to the most hard-to-reach places in the sheds. Stinky-muck. I think somewhere in the attic or in the cellar there are still supplies lying around. Then, after all, they were worn from state farm warehouses.

• Dust

  

  Dust. The word is believed to have originated from English word dust which in English means dust or fine powder. It actually has a more scientific name: DDT.

  And if completely dichlorodiphenyltrichloroethane. Usually used against insects. At the time of perestroika, such an infection as lice went around Russia. Here they were taken out by dust.

If you take the slang meaning of the word dustquot ;, then this is a drug. In fact, the real meaning is not very far in meaning - it is:

In general, this disinfectant.

The name DUST comes from the English word dust, which translates as fine dust or powder. Also known as DDT, the chemical preparation dichlorodiphenyltrichloroethane.

This remedy is very dangerous, but also effective against insect pests, especially against locusts. Currently, its use is prohibited, as it has a detrimental effect on humans, animals and birds.

Dust is the common name for the poison DDT (trichloromethyldimethane). Now this poisonous substance is prohibited, although earlier it could be bought at any hardware store, they poisoned mosquitoes, bed bugs (I know it precisely because of them) and other pests.

But in fact, DDT is harmful not only to insects, but to all living things in general. Dust is very resistant to decomposition, one way or another it enters the food chain and accumulates in plants, animals, and also in the human body.

Modern Dust is an analogue of that old remedy (they used, so to speak, working quot ;, a name familiar to the people), the composition of chemicals in it is already different, more gentle, but still to some extent toxic to humans.

It is also DDT - dichloro-dichlorophenyl-trichloroethane. A toxic substance that was used to kill domestic insects (cockroaches). It was discontinued due to toxicity.

Oh, I remember in my deep childhood I got to the package and the whole kitchen ... I inseccitidil with a thick layer .., and then my parents .. invested my mind ...))))