Poisonous substances. The main damaging properties of toxic substances

Toxic substances are chemical compounds with a high degree of toxicity that are used as chemical weapons. Their special properties include the ability to be used to infect territory, food and military equipment, as well as to tactically defeat the enemy. These chemical compounds penetrate into the human body through the digestive tract, respiratory system, skin pores and mucous membranes.

Review of the most dangerous toxic substances

Chemical weapons created on the basis of toxic substances (CA) were actively used during the First World War. The massive use of chemical warfare agents (CWA) has officially ceased since 1997, although behind the scenes research in this area continues. Data on new developments are under the control of intelligence services and rarely become publicly available. Among the chemical agents that have received publicity, the most dangerous drugs are those from the following list:

Types and classification of toxic substances

The generally accepted physiological classification of toxic substances identifies 7 main categories, taking into account the specifics of their effects on humans:

Sometimes lachrymators and sternites are combined into a common group - irritant toxic substances, or irritants. A number of researchers also identify the following groups toxic substances:

1. Algogens, or pain agents, are compounds that, when they come into contact with the skin, cause hyperemia and severe pain that persist for several hours. Among them are capsaicin, methoxycycloheptatriene, dibenzoxazepine.
2. Emetics, or emetic agents. Their toxic effect mainly affects the functioning of the digestive tract, regardless of the method of entry of the toxin into the body. These include phenylimidophosgene and ethylcarbazole.
3. Malodorants are chemical agents characterized by a sharp, extremely unpleasant odor. They have a moderate or low degree of toxicity and are usually included in mixtures with irritants (for example, in the Israeli drug Skunk).

Depending on the speed of action, in toxicology the following types of toxic substances are distinguished:

• fast-acting - Soman, Sarin, V-gas;
• slow-acting (with a latent period) - lewisite, adamsite, phosgene.

Protection against toxic substances

Since the first use of chemical warfare agents, methods of protection against it have been developed and improved. The degree of damage caused by these compounds depends on the qualifications, training and security of the person. The use of chemical agents for combat purposes leads to death in 5–70% of cases. Among civilians, the mortality rate may be much higher.

Defence from toxic substances depends on following principles:

1. Measures for indication and detection, disinfection of the area.
2. The use of personal protective equipment - gauze bandages, gas masks, self-contained breathing apparatus, rubberized suits.
3. The use of drugs to protect exposed skin areas - antidotes, special creams with filtering and protective properties.
4. Use of collective protective equipment.

The low effectiveness of chemical weapons and the negative assessment from the world community have led to cases of use chemical warfare agents are rare, and are mainly associated with terrorist activities. However, their danger lies in the fact that a number of compounds are actively used in industry and can be released into the atmosphere due to careless handling or an industrial accident.

First aid for poisoning

When the first signs of damage appear toxic substances the victim must be provided with first aid. Symptoms of intoxication may vary depending on the type of specific poison. Employees of industrial enterprises who use chemical agents during their activities must be aware of the necessary measures in the event of an emergency, equipped with protective equipment and appropriate medications.

Severe forms of intoxication chemical warfare agents, as a rule, are fatal, so it is impossible to help the victims in this case. First aid for mild and moderate damage to the OB is carried out according to the following algorithm:

1. Put a gas mask on the victim or replace damaged personal protective equipment with a working one. If the victim is in the area of ​​direct action of the agent, pre-treat the facial skin with liquid from an individual chemical package.
2. In case of damage to the respiratory organs by a suffocating BOV - ensure the immobility of the victims; in the cold season - to warm. It is prohibited to perform artificial respiration - this will lead to intoxication of the person providing assistance.
3. In case of contact with a generally poisonous agent, crush the ampoule with the antidote and put it inside the gas mask. If you are suffocating, perform artificial respiration.
4. If nerve gas poisoning occurs, it is necessary to put a gas mask on the victim and administer an antidote from the first aid kit subcutaneously or intramuscularly. Treat the skin additionally with a chemical package solution.
5. If a person comes into contact with a psychochemical, blister or irritant agent, it is necessary to wash the skin and mucous membranes with soapy water and clean clothes with a brush.

After providing first aid, immediate evacuation of victims from the area of ​​exposure to chemical agents is necessary.

Toxic substances(OV) - toxic chemical compounds designed to destroy enemy personnel during military operations and at the same time preserve material assets during an attack in the city. They can enter the body through the respiratory system, skin and digestive tract. The combat properties (combat effectiveness) of agents are determined by their toxicity (due to the ability to inhibit enzymes or interact with receptors), physicochemical properties (volatility, solubility, resistance to hydrolysis, etc.), ability to penetrate the biobarriers of warm-blooded animals and overcome defenses.

First generation chemical weapons include four groups of toxic substances:
1) OV vesicant action(persistent sulfur and nitrogen mustard agents, lewisite).
2) OV general toxic effect(unstable agent hydrocyanic acid). ;
3) OV suffocating effect(unstable agents phosgene, diphosgene);
4) OV irritating effect(adamsite, diphenylchloroarsine, chloropicrin, diphenylcyanarsine).

The official date of the beginning of the large-scale use of chemical weapons (namely as weapons of mass destruction) should be considered April 22, 1915, when the German army in the area of ​​​​the small Belgian town of Ypres used a chlorine gas attack against the Anglo-French Entente troops. A huge poisonous yellow-green cloud of highly toxic chlorine, weighing 180 tons (out of 6,000 cylinders), reached the enemy’s advanced positions and struck 15 thousand soldiers and officers within a matter of minutes; five thousand died immediately after the attack. Those who survived either died in hospitals or became disabled for life, having received silicosis of the lungs, severe damage to the visual organs and many internal organs.

Also in 1915, on May 31, on the Eastern Front, the Germans used an even more highly toxic toxic substance called phosgene (full carbonic acid chloride) against Russian troops. 9 thousand people died. On May 12, 1917, another battle of Ypres.

And again, German troops use chemical weapons against the enemy - this time the chemical warfare agent of skin, vesicant and general toxic effects - 2,2 dichlorodiethyl sulfide, which later received the name "mustard gas".

During the First World War, other toxic substances were tested: diphosgene (1915), chloropicrin (1916), hydrocyanic acid (1915). Before the end of the war, toxic substances (CA) based on organoarsenic compounds were developed, which have general toxicity and pronounced irritant - diphenylchloroarsine, diphenylcyanarsine.

During the First World War, all warring states used 125 thousand tons of toxic substances, including 47 thousand tons by Germany. About 1 ml suffered from the use of chemical weapons during the war. Human. At the end of the war, the list of potentially promising and already tested chemical agents included chloroacetophenone (lacrymator), which has a strong irritant effect, and, finally, a-lewisite (2-chlorovinyldichloroarsine).

Lewisite immediately attracted close attention as one of the most promising chemical warfare agents. Its industrial production began in the United States even before the end of the World War; our country began producing and accumulating lewisite reserves already in the first years after the formation of the USSR.

The end of the war only slowed down work on the synthesis and testing of new types of chemical warfare agents for some time.

However, between the first and second world wars, the arsenal of deadly chemical weapons continued to grow.

In the thirties, new toxic substances with blister and general toxic effects were obtained, including phosgenoxime and “nitrogen mustards” (trichlorethylamine and partially chlorinated derivatives of triethylamine).

Second generation.
5) OV nerve-paralytic action.
Since 1932, intensive research has been carried out in different countries on organophosphorus nerve agents - second-generation chemical weapons (sarin, soman, tabun). Due to the exceptional toxicity of organophosphorus agents (OPCs), their combat effectiveness increases sharply. During these same years, chemical munitions were improved. In the 50s, a group of FOVs called “V-gases” (sometimes “VX-gases”) was added to the family of second-generation chemical weapons.

First obtained in the USA and Sweden, V-gases of a similar structure soon appear in service in the chemical forces and in our country. V-gases are tens of times more toxic than their “brothers in arms” (sarin, soman and tabun).

Third generation.
6) p psycho-chemical agents

In the 60-70s, third-generation chemical weapons were developed, which included not only new types of toxic substances with unexpected mechanisms of destruction and extremely high toxicity, but also more advanced methods of their use - chemical cluster munitions, binary chemical weapons, etc. R.

The technical idea behind binary chemical munitions is that they are loaded with two or more starting components, each of which can be a non-toxic or low-toxic substance. During the flight of a projectile, rocket, bomb or other ammunition towards a target, the initial components are mixed in it to form a chemical warfare agent as the final product of a chemical reaction. In this case, the role of a chemical reactor is played by ammunition.

In the post-war period, the problem of binary chemical weapons was of secondary importance for the United States. During this period, the Americans accelerated the equipment of the army with new toxic nerve agents, but since the early 60s, American specialists again returned to the idea of ​​​​creating binary chemical munitions. They were forced to do this by a number of circumstances, the most important of which was the lack of significant progress in the search for toxic substances with ultra-high toxicity, i.e. third generation toxic substances.

During the first period of implementation of the binary program, the main efforts of American specialists were aimed at developing binary compositions of the standard nerve agents, VX and sarin.

Along with the creation of standard binary 0B, the main efforts of specialists are, of course, focused on obtaining more effective 0B. Serious attention was paid to the search for binary 0B with so-called intermediate volatility. Government and military circles explained the increased interest in work in the field of binary chemical weapons by the need to solve problems of the safety of chemical weapons during production, transportation, storage and operation.

An important stage in the development of binary ammunition is the actual design development of shells, mines, bombs, missile warheads and other means of use.

Physiological classification.

The physiological classification, like all others, is very conditional. On the one hand, it allows you to combine into a single system of measures for decontamination and protection, sanitization and first aid for each group. On the other hand, it does not take into account the presence of side effects in some substances, which sometimes pose a great danger to the affected person. For example, irritant substances PS and CN can cause severe lung damage, even death, and DM causes general poisoning of the body with arsenic. Although it is accepted that the intolerable concentration of irritating substances should be at least 10 times lower than the lethal one, in real conditions of using chemical agents this requirement is practically not observed, as evidenced by numerous facts of the severe consequences of the use of police substances abroad. Some 0B in their effect on the body can be simultaneously classified into two or more groups. In particular, substances VX, GB, GD, HD, L have an unconditionally generally toxic effect, and substances PS, CN have a suffocating effect. In addition, new 0Bs appear from time to time in the arsenal of chemical weapons of foreign countries, which are generally difficult to attribute to any of the six groups mentioned above. Tactical classification.

The tactical classification divides 0B into groups according to combat purpose. In the US Army, for example, all 0V are divided into two groups:

Deadly(according to American terminology, lethal agents) are substances intended to destroy manpower, which include nerve agents, vesicants, general poisonous and asphyxiating agents;

Temporarily incapacitating personnel(in American terminology, harmful agents) are substances that allow solving tactical problems of incapacitating manpower for periods from several minutes to several days. These include psychotropic substances (incapacitants) and irritants (irritants).

Sometimes a group of irritants, as substances that incapacitate manpower for a period of time slightly exceeding the period of direct exposure to 0B and measured in minutes - tens of minutes, are classified as a special group of police substances. Obviously, the goal here is to exclude them from combat weapons in the event of a ban on chemical weapons. In some cases, educational agents and formulations are included in a separate group.

The tactical classification of 0B is also imperfect. Thus, the group of lethal chemical agents includes the most diverse compounds in terms of physiological action, and all of them are only potentially fatal, because the final result of the action of 0B depends on its toxicity, the toxodoses entering the body and the conditions of use. The classification does not take into account such important factors as the chemical discipline of manpower exposed to a chemical attack, the provision of its means of protection, the quality of means of protection, the condition of weapons and military equipment. However, physiological and tactical classifications of 0B are used when studying the properties of specific compounds.

Often in the literature, tactical classifications of 0B are given, based on taking into account the speed and duration of their destructive effect, and suitability for solving certain combat missions.

There are, for example, fast-acting and slow-acting agents depending on whether they have a period of latent action or not. Fast-acting substances include nerve-paralytic, generally toxic, irritating and some psychotropic substances, i.e. those that lead to death within a few minutes or to loss of combat capability (performance) as a result of temporary damage. Slow-acting substances include blisters, asphyxiants and certain psychotropic substances that can destroy or temporarily incapacitate people and animals only after a period of latent action lasting from one to several hours. This separation of 0B is also imperfect, because some slow-acting substances, if introduced into the atmosphere in very high concentrations, will cause damage in a short time, with virtually no period of latent action.

Depending on the duration of preservation of the damaging ability, agents are divided into short-acting (unstable or volatile) and long-acting (persistent). The damaging effect of the former is calculated in minutes (AC, CG). The action of the latter can last from several hours to several weeks after their use, depending on meteorological conditions and the nature of the terrain (VX, GD, HD). This division of 0B is also conditional, since short-acting 0B often becomes long-acting in the cold season.

The systematization of 0B and poisons in accordance with the tasks and methods of their use is based on the isolation of substances used in offensive and defensive combat operations, as well as in ambushes or sabotage. Sometimes there are also groups of chemical means for destroying vegetation or removing foliage, means for destroying certain materials, and other groups of means for solving specific combat missions. The conventionality of all these classifications is obvious.

There is also a classification of chemical agents according to serviceability categories. In the US Army they are divided into groups A, B, C. Group A includes service chemical ammunition, which at this stage most fully satisfies the tactical and technical requirements for them. Group B includes spare service chemical ammunition, which in terms of basic tactical and technical requirements is inferior to group A samples, but can replace them if necessary. Group C includes weapons that are currently out of production, but may be in service until their reserves are used up. In other words, group C includes weapons equipped with obsolete toxic substances.

The most common tactical and physiological classifications of OM.

Tactical classification:
According to the elasticity of saturated vapors(volatility) are classified into:
unstable (phosgene, hydrocyanic acid);
persistent (mustard gas, lewisite, VX);
poisonous fumes (adamsite, chloroacetophenone).

By the nature of the impact on manpower:
lethal: (sarin, mustard gas);
temporarily incapacitating personnel: (chloroacetophenone, quinuclidyl-3-benzilate);
irritants: (adamsite, Cs, Cr, chloroacetophenone);
educational: (chloropicrin);

According to the speed of onset of the damaging effect:
fast-acting - do not have a period of latent action (sarin, soman, VX, AC, Ch, Cs, CR);
slow-acting – have a period of latent action (mustard gas, Phosgene, BZ, lewisite, Adamsite);

Physiological classification

According to physiological classification, they are divided into:
nerve agents: (organophosphorus compounds): sarin, soman, tabun, VX;

Generally toxic agents: hydrocyanic acid; cyanogen chloride;
blister agent: mustard gas, nitrogen mustard gas, lewisite;
Agents that irritate the upper respiratory tract or sternites: adamsite, diphenylchloroarsine, diphenylcyanarsine;
asphyxiating agents: phosgene, diphosgene;
irritating agents or lachrymators: chloropicrin, chloroacetophenone, dibenzoxazepine, o-chlorobenzalmalondinitrile, bromobenzyl cyanide;
psychochemical agents: quinuclidyl-3-benzilate.

Chemical agents (CW, BOV - nrk; synonym: chemical warfare agents - nrk) - highly toxic chemical compounds intended for use in war for the purpose of destroying or incapacitating enemy personnel; adopted by armies in a number of capitalist states.

Fast-acting poisonous substances- O. v., clinical signs of damage to which appear a few seconds or minutes after their effect on the body.

Toxic substances that temporarily incapacitate- O. v., causing reversible processes in the human body that temporarily interfere with the performance of professional (combat) activities.

Delayed-acting poisonous substances- O. v., clinical signs of damage which appear after a latent period lasting several tens of minutes or more.

Poisonous substances with blister action(syn.: vesicants, toxic substances vesicants - nrk) - O. v., the toxic effect of which is characterized by the development of an inflammatory-necrotic process at the site of contact, as well as a resorptive effect, manifested by dysfunction of vital organs and systems.

Skin-resorptive toxic substances- O. v., capable of penetrating the body upon contact with intact skin.

Nerve agents(syn.: nerve gases - NRG, nerve agent toxicants) - fast-acting O. v., the toxic effect of which is manifested by dysfunction of the nervous system with the development of miosis, bronchospasm, muscle fibrillation, sometimes general convulsions and flaccid paralysis, as well as dysfunction other vital organs and systems.

Poisonous substances are unstable(NOV) - gaseous or rapidly evaporating liquid O. v., the damaging effect of which lasts no more than 1-2 hours after use.

Generally poisonous substances- O. v., the toxic effect of which is characterized by rapid inhibition of tissue respiration and the development of signs of hypoxia.

Poisonous substances police- temporarily disabling O. v. irritant and tear action.

Poisonous substances of psychotomimetic action(syn.: O. v. psychotic, O. v. psychotomimetic, O. v. psychochemical) - O. v. causing temporary mental disorders, usually without pronounced disturbances in the activity of other organs and systems.

Irritating toxic substances(syn. sneezing toxic substances) - fast-acting O. v., the toxic effect of which is characterized by irritation of the mucous membranes of the respiratory tract.

Tear-acting toxic agents(syn. lachrimators) - fast-acting O. v., the toxic effect of which is characterized by irritation of the mucous membranes of the eyes and nasopharynx.

Poisonous substances are persistent(OWL) - O. v., the damaging effect of which persists for several hours or days after application.

Asphyxiating agents- O. v., the effect of which is characterized by the development of toxic pulmonary edema.

Organophosphorus poisonous substances(FOV) - O. v., which are organic esters of phosphoric acids; belong to O. v. neuroparalytic action.

New generation - Substances that can be used in combat situations.
There are many groups of substances that have attractive military properties. Often the assignment of a substance to one group or another is very conditional and is made according to the primary purpose of the action on the object.
Deadly
Substances of this group are intended to destroy enemy personnel, domestic and farm animals.

GABA agonists (convulsant poisons) are highly toxic substances, usually of a bicyclic structure. Relatively simple in structure, stable to hydrolysis. Examples: bicyclophosphates (tert-butyl bicyclophosphate), TATS, flucibenes, arylsilatranes (phenylsilatrane).
Bronchoconstrictors are bioregulators. They have a bronchoconstrictor effect, leading to death from respiratory failure. Examples: leukotrienes D and C.
Hyperallergens (nettle poisons) are a relatively new group of toxic substances. The peculiarity of the action is sensitization of the body with subsequent provocation of an acute allergic reaction. The main disadvantage is the effect of the second dose - upon first entry into the body, they have a much weaker effect than upon repeated administration. Examples: phosgenokee, urushiols.
Cardiotoxins are substances that selectively affect cardiac activity. Examples: cardiac glycosides.
Blisters are substances used by the military since World War I. They are standard toxic substances. Significantly less toxic than organophosphates. The main military advantage is the delayed lethal effect with a crippling effect; this requires the enemy to expend effort and resources to provide medical care to the injured. Examples: sulfur mustard, sesquimustard, oxygen mustard, nitrogen mustard, lewisite.
Nerve agents - organophosphorus substances of this group cause death by any route of ingestion. Highly toxic (high toxicity in contact with skin is especially attractive). They are used as standard toxic substances. Examples: sarin, soman, tabun, VX, aromatic carbamates.
Systemic poisons (generally poisonous) - simultaneously affect many body systems. Some of them were in service with various countries. Examples: hydrocyanic acid, cyanides, fluoroacetates, dioxin, metal carbonyls, tetraethyl lead, arsenides.
Toxins are substances that have extremely high toxicity with a wide variety of symptoms. The main disadvantages of natural toxins, from a military point of view, are their solid state of aggregation, inability to penetrate the skin, high price, and instability to detoxification. Examples: tetrodotoxin, palytoxin, botulinum toxins, diphtheria toxin, ricin, mycotoxins, saxitoxin.
Toxic alkaloids are substances of different structures produced by plants and animals. Due to their relative availability, these substances can be used as toxic agents. Examples: nicotine, coniine, aconitine, atropine, C-toxiferine I.
Heavy metals are inorganic substances that can cause fatal injuries of both acute and chronic nature. They have greater ecotoxic significance, as they persist for a long time in the natural environment. Examples: thallium sulfate, mercuric chloride, cadmium nitrate, lead acetate.
Asphyxiants are long-known standard toxic substances. The exact mechanism of their action is unknown. Examples: phosgene, diphosgene, triphosgene.

Mutilating
Substances in this group provoke a long-term illness that can be fatal. Some researchers also include blister substances here.

Causing neurolatyrism - cause specific damage to the central nervous system, leading to the movement of animals in a circle. Examples: IDPN.
Carcinogenic - a group of substances that provoke the development of cancerous tumors. Examples: benzopyrene, methylcholanthrene.
Hearing impairing - used to damage the human hearing system. Examples: antibiotics of the streptomycin group.
Irreversible paralytics are a group of substances that cause demyelination of nerve fibers, which leads to paralysis of varying extent. Examples: tri-ortho-cresyl phosphate.
Affects vision - causes temporary or permanent blindness. Example: methanol.
Radioactive - cause acute or chronic radiation sickness. They can have almost any chemical composition, since all elements have radioactive isotopes.
Supermutagens are substances that provoke the occurrence of genetic mutations. May also be included in various other groups (often, for example, highly toxic and carcinogenic). Examples: nitrosomethylurea, nitrosomethylguanidine.
Teratogens are a group of substances that cause deformities during fetal development during pregnancy. The purpose of military use may be genocide or preventing the birth of a healthy child. Examples: thalidomide.

Non-lethal
The purpose of using substances in this group is to render a person incapacitated or create physical discomfort.

Algogens are substances that cause severe pain when they come into contact with the skin. Currently, there are compositions sold for self-defense of the population. They often also have a lachrymatory effect. Example: 1-methoxy-1,3,5-cycloheptatriene, dibenzoxazepine, capsaicin, pelargonic acid morpholide, resiniferatoxin.
Anxiogens cause an acute panic attack in a person. Examples: cholecystokinin type B receptor agonists.
Anticoagulants - reduce blood clotting, causing bleeding. Examples: superwarfarin.
Attractants – attract various insects or animals (for example, stinging, unpleasant) to a person. This can lead to a panic reaction in a person or provoke an insect attack on a person. They can also be used to attract pests to enemy crops. Example: 3,11-dimethyl-2-nonacosanone (cockroach attractant).
Malodorants - cause the removal of people from the territory or from a certain person due to people’s aversion to the unpleasant odor of the area (person). Either the substances themselves or the products of their metabolism can have an unpleasant odor. Examples: mercaptans, isonitriles, selenols, sodium tellurite, geosmin, benzcyclopropane.
Causing muscle pain – cause severe pain in a person’s muscles. Examples: thymol amino esters.
Antihypertensives - greatly reduce blood pressure, causing orthostatic collapse, as a result of which a person loses consciousness or the ability to move. Example: clonidine, canbisol, platelet activating factor analogues.
Castrators - cause chemical castration (loss of reproduction). Examples: gossypol.
Catatonic - cause the development of catatonia in those affected. Usually referred to as a type of psychochemical toxic substance. Examples: bulbocapnin.
Peripheral muscle relaxants - cause complete relaxation of skeletal muscles. Can cause death due to relaxation of respiratory muscles. Examples: tubocurarine.
Central muscle relaxants - cause relaxation of skeletal muscles. Unlike peripheral ones, they have less effect on breathing and their detoxification is difficult. Examples: muscle relaxin, phenylglycerol, benzimidazole.
Diuretics - cause a sharp acceleration in bladder emptying. Examples: furosemide.
Anesthetic - cause anesthesia in healthy people. So far, the use of this group of substances is hampered by the low biological activity of the substances used. Examples: isoflurane, halothane.
Truth drugs cause a state in people where a person cannot consciously tell a lie. It has now been shown that this method does not guarantee the complete truthfulness of a person and their use is limited. Usually these are not individual substances, but a combination of barbiturates and stimulants.
Narcotic analgesics - in doses above therapeutic ones have an immobilizing effect. Examples: fentanyl, carfentanil, 14-methoxymetopone, etorphine, afin.
Memory Impairing - Causes temporary memory loss. Often toxic. Examples: cycloheximide, domoic acid, many anticholinergics.
Neuroleptics - cause motor and mental retardation in humans. Examples: haloperidol, spiperone, fluphenazine.
Irreversible MAO inhibitors are a group of substances that block monoamine oxidase. As a result, when consuming foods high in natural amines (cheeses, chocolate), a hypertensive crisis is provoked. Examples: nialamide, pargyline.
Will suppressors - cause impairment of the ability to make independent decisions. They are substances of different groups. Example: scopolamine.
Prurigens - cause intolerable itching. For example: 1,2-dithiocyanoethane.
Psychotomimetic drugs - cause psychosis that lasts for some time, during which a person cannot make adequate decisions. Example: BZ, LSD, mescaline, DMT, DOB, DOM, cannabinoids, PCP.
Laxatives cause a sharp acceleration in the emptying of intestinal contents. With prolonged use of drugs in this group, exhaustion of the body may develop. Examples: bisacodyl.
Lachrymators (lacrimators) cause severe lacrimation and closure of a person's eyelids, as a result of which the person temporarily cannot see what is happening around him and loses his fighting ability. There are standard toxic substances used to disperse demonstrations. Examples: chloroacetophenone, bromoacetone, bromobenzyl cyanide, ortho-chlorobenzylidene malonodinitrile (CS).
Sleeping pills – cause a person to fall asleep. Examples: flunitrazepam, barbiturates.
Sternites - cause uncontrollable sneezing and coughing, as a result of which a person can throw off the gas mask. There are report cards. Examples: adamsite, diphenylchloroarsine, diphenylcyanarsine.
Tremorgens - cause convulsive twitching of skeletal muscles. Examples: tremorine, oxotremorine, tremorgenic mycotoxins.
Photosensitizers - increase skin sensitivity to solar ultraviolet rays. When going out into sunlight, a person can get painful burns. Examples: hypericin, furocoumarins.
Emetics (emetics) - cause a gag reflex, as a result of which being in a gas mask becomes impossible. Examples: apomorphine derivatives, staphylococcal enterotoxin B, PHNO.

Toxic substances are poisonous chemical compounds that serve to defeat enemy forces during war. They have a number of physical and chemical properties, due to which in a combat situation they can be in a liquid, aerosol or vapor state and are the basis of chemical mass destruction). Agents penetrate into various open rooms, shelters or structures and affect living organisms that are located there, maintaining their effect for a certain period of time after their use.

Chemical warfare agents enter the human body in several ways: through the skin, respiratory or digestive organs, and mucous membranes. Moreover, the degree and nature of the damage depend on the routes of entry into the body, the rate of distribution throughout it and removal from it, as well as on the modes of action of toxic substances and the individual characteristics of the human body.

To date, there is no specific classification of these substances. Of greatest importance are:

1. Physiological classification (according to the effect on the body). These include unstable toxic substances, persistent and toxic-smoky agents.

a) unstable OM - capable of contaminating the atmosphere, they form a vapor cloud that spreads throughout and dissipates quite quickly.

b) persistent agents - liquid substances that create a cloud that is contaminated with an aerosol. Some of the chemicals settle in the form of dew on the surrounding area.

c) smoky agents - used in the form of various smokes and consist of

2. Tactical classification (based on behavior on the ground). This includes lethal toxic substances that incapacitate for a certain period of time and irritate agents.

a) lethal action - serve to eliminate living organisms.

b) incapacitating - serve to create a mental disorder in people.

c) irritants - serve to exhaust people.

Also, based on the nature of the effect on the human body, the following are distinguished:

1. Nerve agents (sarin, VX, soman) - contain phosphorus and are therefore highly toxic. They have the ability to accumulate and affect the human nervous system whenever they enter the body. These are colorless, odorless liquids that dissolve well in natural solvents, but least of all in water.

2. Toxic agents (phosphine, arsine, hydrocyanic acid) - disrupt tissue respiration, stopping their oxidative processes. These substances enter the body through the respiratory system and gastrointestinal tract.

3. Asphyxiants (chloropicrin, diphosgene and phosgene) - affect the lung tissue and upper respiratory tract, causing suffocation and death.

4. Irritating toxic substances (CS, dibenzoxazepine, chloroacetophenone) - contributes to irritation of the mucous membranes of the respiratory system and eyes. Used in aerosol form, causing burns, respiratory paralysis, and death.

5. Blistering agents (lewisite, mustard gas) - enter the body through the skin and mucous membrane, causing poisoning and the formation of ulcers at points of contact with the skin.

6. Psychogenic substances (OB, BZ) - cause psychosis and physical disorders by interrupting neuromuscular transmission of impulses.

7. Toxins (botulinum, staphylococcal enteroxin) - cause paralysis of the central nervous system, vomiting, poisoning of the body.

Thus, to date, almost all types of toxic substances have been studied. All of them are capable of affecting the human body, causing its poisoning. For timely protection, it is important to quickly detect the agent, establish its type and concentration. Only then can high results be achieved in providing medical care to victims during military operations.

TOXIC WARFARE AGENTS(formerly known as “combat gases”, “choking agents”), artificial chemical products used in war to destroy living targets - humans and animals. Toxic substances are the active principle of the so-called. chemical weapons and serve directly to cause damage. The concept of toxic substances includes such chemical compounds that, when used properly, are capable of incapacitating an unprotected fighter by poisoning him. Poisoning here refers to any disruption of the normal functioning of the body - from temporary irritation of the eyes or respiratory tract to long-term illness or death.

Story . The beginning of the combat use of toxic substances is considered to be April 22, 1915, when the Germans launched the first chlorine gas attack against the British. Since mid-1915, chemical shells with various toxic substances were widely used in the war. At the end of 1915, the Russian army began to use chloropicrin. In February 1916, the French introduced phosgene into combat practice. In July 1917, the German army used mustard gas (a blister poisonous substance) in combat operations, and in September 1917 it introduced arsines (see Combat arsines) - arsenic-containing toxic substances used in the form of toxic smoke and fog. The total number of different toxic substances used in the world war reached 70. Currently, the armies of almost all countries have various types of toxic substances in their arsenal, which will undoubtedly be used in future military clashes. Further research to improve methods of production and use of already known toxic substances is being carried out in all major countries.

Combat use of chemical agents carried out by introducing them into the atmosphere in the form of vapor, smoke or fog, or by applying toxic substances to the surface of the soil and local objects. The most convenient and commonly used medium for introducing toxic substances into the body is air; in certain cases, this role can be played by soil, water, vegetation, food products and all artificial structures and objects. To cause damage through the air, it is necessary to create a certain “combat” concentration of toxic substances, calculated in weight units (mg per liter of air) or volume (% or ‰). When soil is contaminated, a certain “contamination density” is required, calculated in grams of toxic substances per m 2 of surface. To bring toxic substances into an active state and to transfer them by the attacking side to the objects of attack, special mechanical devices are used that make up material part chemical attack techniques.

During the World War, toxic substances were used in the following methods of chemical attack: 1) gas cylinder attack, i.e., the release of a gaseous toxic substance from special cylinders, carried to the enemy by the wind in the form of a poisoned wave of air; 2) firing of field artillery with chemical shells containing toxic substances and an explosive charge; 3) firing chemical mines from ordinary or special mortars (gas launchers) and 4) throwing hand and rifle chemical grenades. Currently, the following methods have been developed: 5) burning special candles that produce toxic smoke when burned; 6) direct contamination of the area with toxic substances through ground-based (portable) devices; 7) bombing from aircraft with aerochemical bombs; and 8) direct spraying or spraying of toxic substances from aircraft over the surface of the earth.

Toxic substances as weapons characterized by a massive destructive effect. The main difference from mechanical weapons is that the damaging effect of toxic substances is chemical, based on the interaction of the toxic substance with the tissues of a living organism, and causes a certain combat effect as a result of a known chemical process. The effect of various toxic substances is extremely diverse: it can vary widely and take a variety of forms; the lesion usually involves a huge number of living cells (general poisoning of the body). Other features of toxic substances as weapons are: a) high fragmentation of the substance at the moment of action (up to individual molecules, about 10 -8 cm in size, or particles of smoke and fog, 10 -4 -10 -7 cm in size), due to which a continuous zone is created lesions; b) the ability to spread in all directions and penetrate with air through small holes; c) duration of action (from several minutes to several weeks) and d) for some toxic substances the ability to act slowly (not immediately) or gradually and imperceptibly accumulate in the body until quantities dangerous to life are formed (“cumulation” of toxic substances).

Requirements for toxic substances, are set by tactics, military equipment and supply agencies. They boil down mainly to the following conditions: 1) high toxicity (degree of toxic action), i.e. the ability of toxic substances to incapacitate in low concentrations and with short-term effects, 2) difficulty of defense for the enemy, 3) ease of use for the attacking side , 4) ease of storage and transportation, 5) availability of production in large quantities and low cost. Requirement (5) implies the need for a close link between the production of toxic substances and the country’s peaceful chemical industry. Satisfaction of all these requirements is achieved by proper selection of the physical, chemical and toxic properties of toxic substances, as well as by improving the methods of their production and use.

Tactical characteristics of toxic substances. Toxic substances that are slow to fly and have high chemical strength are called persistent (for example, mustard gas). Such toxic substances are capable of having a long-lasting damaging effect in the place where they were released from the shell; therefore, they are suitable for pre-contamination of areas in order to make them inaccessible or impassable (gas plugs). On the contrary, highly volatile or quickly decomposing toxic substances are classified as unstable, acting for a short time. The latter also include toxic substances used in the form of smoke.

Chemical composition of toxic substances. Almost all toxic substances, with few exceptions, are organic, i.e., carbon compounds. The composition of the various toxic substances known to date included only the following 9 elements: carbon, hydrogen, oxygen, chlorine, bromine, iodine, nitrogen, sulfur and arsenic. Among the toxic substances used were representatives of the following classes of chemical compounds: 1) inorganic - free halides and acid chlorides; 2) organic - halogenated hydrocarbons, ethers (simple and complex), ketones, mercaptans and sulfides, acid chlorides of organic acids, unsaturated aldehydes, nitro compounds, cyanide compounds, arsines, etc. The chemical composition and structure of the molecule of toxic substances determine all their other properties, important in combat terms.

Nomenclature. To designate toxic substances, either their rational chemical names are used (chlorine, bromoacetone, diphenylchloroarsine, etc.), or special military terms (mustard gas, lewisite, surpalite), or, finally, conventional codes (D. M., K., yellow cross). Conventional terms were also used for mixtures of toxic substances (martonite, palit, vincennite). During the war, poisonous substances were usually encrypted to keep their composition secret.

Individual representatives The most important poisonous substances used in the World War or described in post-war literature are listed in the accompanying table, together with their most important properties.

Physical properties of toxic substances, affecting their combat suitability: 1) vapor pressure, which should b. significant at normal temperatures, 2) evaporation rate or volatility (high for unstable toxic substances and low for persistent ones), 3) evaporation limit (maximum achievable concentration), 4) boiling point (low for unstable toxic substances and high for persistent ones), 5 ) melting point, 6) state of aggregation at ordinary temperature (gases, liquids, solids), 7) critical temperature, 8) heat of vaporization, 9) specific gravity in liquid or solid state, 10) vapor density of toxic substances (d.b . greater than the density of air), 11) solubility (mainly in water and substances of the animal body), 12) the ability to be adsorbed (absorbed) by antigas carbon (see Activated carbon), 13) the color of toxic substances and some other properties.

Chemical properties of toxic substances depend entirely on their composition and structure. From a military point of view, the following are of interest: 1) the chemical interaction of toxic substances with substances and tissues of the animal body, which determines the nature and degree of toxicity of the toxic substances and is the reason for their damaging effect; 2) the ratio of toxic substances to water (the ability to decompose with water - hydrolysis); 3) relation to air oxygen (oxidizability); 4) attitude towards metals (corrosive effect on shells, weapons, mechanisms, etc.); 5) the possibility of neutralizing toxic substances using available chemical means; 6) the ability to recognize toxic substances using chemical reagents and 7) the smell of toxic substances, which also depends on the chemical nature of the substances.

Toxic properties of toxic substances. The variety of toxic effects of toxic substances is determined by the diversity of their composition and structure. Substances that are similar in chemical nature act in a similar way. The carriers of toxic properties in the molecule of a toxic substance are certain atoms or groups of atoms - “toxophores” (CO, S, SO 2, CN, As, etc.), and the degree of action and its shades are determined by accompanying groups - “auxotoxes”. The degree of toxicity, or the strength of action of toxic substances, is determined by the minimum damaging concentration and time of action (exposure): the smaller these two values, the higher it is. The nature of toxicity is determined by the routes of penetration of toxic substances into the body and the predominant effect on certain organs of the body. According to the nature of their action, toxic substances are often divided into asphyxiants (affecting the respiratory tract), lachrymators (lacrimators), poisonous (acting on the blood or nervous system), vesicants (acting on the skin), irritants or “sneezing” (acting on the mucous membranes of the nose). and upper respiratory tract), etc.; the characteristic is given by the “predominant” effect, since the effect of toxic substances on the body is very complex. Combat concentrations of various toxic substances vary from a few mg to ten thousandths of a mg per liter of air. Some toxic substances cause fatal injuries when introduced into the body in doses of about 1 mg or even less.

Production of toxic substances requires the country to have large reserves of accessible and cheap raw materials and a developed chemical industry. Most often, the equipment and personnel of existing chemical plants for peaceful purposes are used to produce toxic substances; Sometimes special installations are also built (Edgewood Military Chemical Arsenal in the USA). The peaceful chemical industry has raw materials in common with the production of toxic substances, or produces finished intermediate products. The main branches of the chemical industry that provide material for toxic substances are: electrolysis of table salt, coke-benzene and wood-acetomethyl production, production of bound nitrogen, arsenic compounds, sulfur, distillery, etc. Artificial paint factories were usually used for the production of toxic substances.

Determination of toxic substances can be produced in laboratory or field conditions. Laboratory determination represents an accurate or simplified chemical analysis of toxic substances using conventional methods of analytical chemistry. Field determination aims to: 1) detect the presence of toxic substances in the air, water or soil, 2) determine the chemical nature of the toxic substance used, and 3) determine its concentration, if possible. The 1st and 2nd problems are solved simultaneously with the help of special chemical reagents - “indicators” that change their color or release a precipitate in the presence of a certain toxic substance. For colorful reactions, liquid solutions or pieces of paper soaked in such solutions are used; for sedimentary reactions - only liquids. Reagent d.b. specific, sensitive, acting quickly and sharply, not changing during storage; using it d.b. simple. The 3rd problem is rarely solvable in the field; For this purpose, special devices are used - gas detectors, based on known chemical reactions and allowing one to approximately judge the concentration of toxic substances by the degree of color change or by the amount of precipitate that falls. Detection of toxic substances using physical methods (change in diffusion rate) or physicochemical methods (change in electrical conductivity as a result of hydrolysis of toxic substances), which has been proposed many times, has turned out to be very unreliable in practice.

Protection against toxic substances can be individual and collective (or mass). The first is achieved by using gas masks that isolate the respiratory tract from the surrounding air or purify the inhaled air from toxic substances, as well as special insulating clothing. Collective protection means include gas shelters; to mass protection measures - degassing, used mainly for persistent toxic substances and consisting in neutralizing toxic substances directly on the ground or on objects using “neutralizing” chemical materials. In general, all methods of protection against toxic substances come down to either the creation of impenetrable partitions (mask, clothing), or to filtering the air used for breathing (filtering gas mask, gas shelter), or to a process that would destroy toxic substances (degassing).

Peaceful use of chemical agents. Some toxic substances (chlorine, phosgene) are starting materials for various branches of the peaceful chemical industry. Others (chloropicrin, hydrocyanic acid, chlorine) are used in the fight against pests of plants and baked goods - fungi, insects and rodents. Chlorine is also used for bleaching and for sterilizing water and food products. Some toxic substances are used for preservative impregnation of wood, in the gold industry, as solvents, etc. There are attempts to use toxic substances in medicine for medicinal purposes. However, most of the toxic substances that are most valuable in combat have no peaceful use.

Chemical weapons are weapons whose destructive effect is based on the use of the toxic properties of toxic substances (CA).

Agents include toxic chemical compounds intended to inflict mass casualties on manpower during combat use. Some chemical agents are designed to kill vegetation.

Chemical agents are capable of highly effective destruction of manpower over large areas without destroying material assets, penetrate into cabins, shelters and structures that do not have special equipment, retain their destructive effect for a certain time after their use, contaminate the area and various objects, and have a negative psychological effect for personnel. In the shells of chemical munitions, toxic substances are in a liquid or solid state. At the moment of use, they, freed from the shell, turn into a combat state: vapor (gaseous), aerosol (smoke, fog, drizzle) or droplet-liquid. In the state of vapor or gas, OM are fragmented into individual molecules, in the state of fog - into tiny droplets, in the state of smoke - into tiny solid particles.

The most common tactical and physiological classifications of OS (Fig. 4).

In the tactical classification, toxic substances are divided into:

1. By saturated vapor pressure (volatility) on:

• unstable (phosgene, hydrocyanic acid);
• persistent (mustard gas, lewisite, VX);
• poisonous fumes (adamsite, chloroacetophenone).

2. By the nature of the impact on manpower on:

• lethal (sarin, mustard gas);
• temporarily incapacitating personnel (chloroacetophenone, quinuclidyl-3-benzilate);
• irritants: (adamsite, chloroacetophenone);
• educational: (chloropicrin);

3. According to the speed of onset of the damaging effect on:

• fast-acting - do not have a period of latent action (sarin, soman, VX, AC, Ch, Cs, CR);
• slow acting - have a period of latent action (mustard gas, Phosgene, BZ, Louisite, Adamsite).

Rice. 4. Classification of toxic substances

In the physiological classification (according to the nature of the effect on the human body), toxic substances are divided into six groups:

1. Nervous agents.
2. Blisters.
3. Generally poisonous.
4. Suffocating.
5. Annoying.
6. Psychochemical.

TO nerve agent (NOV) include: VX, sarin, soman. These substances are colorless or slightly yellowish liquids that are easily absorbed into the skin, various paints and varnishes, rubber products and other materials, and easily accumulate on fabrics. The lightest of the NOVs is sarin, so its main combat state when used is steam. In its vapor state, sarin causes damage mainly through the respiratory system.

Sarin vapors can penetrate the human body through the skin; the magnitude of its fatal toxodose is 200 times higher than when inhaling the vapors. In this regard, it is unlikely that personnel protected by gas masks will be affected by sarin vapor in the field.

OM VX has low volatility, and its main combat state is a coarse aerosol (drizzle). The agent is intended to destroy manpower through the respiratory system and unprotected skin, as well as for long-term contamination of the area and objects on it. VX is several times more toxic than sarin when exposed through the respiratory system and hundreds of times more toxic when exposed through the skin in droplet form. A drop of a few mg of VX on exposed skin is enough to cause fatal injury to a person. Due to the low volatility of VX, contamination of the air with its vapor through the evaporation of droplets deposited on the soil will be insignificant. In this regard, damage to personnel protected by gas masks by VX vapors in field conditions is practically excluded.

NOMs are quite resistant to the action of water, so they can contaminate stagnant bodies of water for a long time: sarin for up to 2 months, and VX for up to six months or more.

Soman's properties are intermediate between sarin and VX.

When a person is exposed to small toxodoses of NO, vision deterioration is observed due to constriction of the pupils of the eyes (miosis), difficulty breathing, and a feeling of heaviness in the chest appears. These phenomena are accompanied by severe headaches and can last for several days. When the body is exposed to fatal toxodoses, severe miosis, suffocation, profuse salivation and sweating are observed, a feeling of fear, vomiting, attacks of severe convulsions, and loss of consciousness appear. Death often occurs from respiratory and cardiac paralysis.

TO blister agent This refers primarily to distilled (purified) mustard gas, which is a colorless or slightly yellowish liquid. Mustard gas is easily absorbed into various paints, rubber and porous materials. The main combat state of mustard gas is droplet-liquid or aerosol. Possessing great resistance, mustard gas is capable of creating dangerous concentrations over contaminated areas, especially in summer; it is capable of infecting water bodies, but is poorly soluble in water.

Mustard gas has a multifaceted damaging effect. When acting in droplet-liquid, aerosol and vapor states, it causes not only damage to the skin, but also general poisoning of the nervous and cardiovascular systems when absorbed into the blood. A feature of the toxic effect of mustard gas is that it has a period of latent action. Skin damage begins with redness, which appears 2-6 hours after exposure. After a day, small blisters filled with a yellow transparent liquid form at the site of redness. After 2-3 days, the blisters burst and ulcers form that do not heal for 20-30 days. When inhaling mustard gas vapors or aerosols, the first signs of damage appear after a few hours in the form of dryness and burning in the nasopharynx. In severe cases, pneumonia develops. Death occurs within 3-4 days. The eyes are especially sensitive to mustard vapors. When exposed to vapors, there is a feeling of the eyes being clogged with sand, lacrimation and photophobia, then swelling of the eyelids occurs. Eye contact with mustard gas almost always results in blindness.

Generally poisonous agents disrupt the activity of many organs and tissues, primarily the circulatory and nervous systems. A typical representative of common toxic agents is cyanogen chloride, which is a colorless gas (at a temperature< 13°С — жидкость) с резким запахом. Хлорциан является быстродействующим ОВ. Он устойчив к действию воды, хорошо сорбируется пористыми материалами. Основное боевое состояние – газ. Ввиду хорошей сорбируемости обмундирования необходимо учитывать возможность заноса хлорциана в убежище. Хлорциан поражает человека через органы дыхания и вызывает неприятный металлический привкус во рту, раздражение глаз, чувство горечи, царапанье в горле, слабость, головокружение, тошноту и рвоту, затруднение речи. После этого появляется чувство страха, пульс становится редким, а дыхание – прерывистым. Поражённый теряет сознание, начинается приступ судорог и наступает паралич. Смерть наступает от остановки дыхания. При поражении хлорцианом наблюдается розовая окраска лица и слизистых оболочек.

TO suffocating include agents that affect human lung tissue. This is, first of all, phosgene, which is a colorless gas (at temperatures below 80C it is liquid) with an unpleasant odor of rotten hay. Phosgene has low resistance, but since it is heavier than air, at high concentrations it can “flow” into the cracks of various objects. Phosgene affects the body only through the respiratory system and causes pulmonary edema, which leads to disruption of the supply of air oxygen to the body, causing suffocation. There is a period of latent action (2-12 hours) and cumulative action. When inhaling phosgene, mild irritation of the mucous membrane of the eyes, lacrimation, dizziness, cough, chest tightness, and nausea are felt. After leaving the infected area, these phenomena disappear within a few hours. Then suddenly there is a sharp deterioration in the condition, a strong cough with copious sputum production, headache and shortness of breath, blue lips, eyelids, cheeks, nose, increased heart rate, pain in the heart, weakness, suffocation, and an increase in temperature to 38-390C. Pulmonary edema lasts several days and is usually fatal.

TO irritating agent include CS type OM, chloroacetophenone, adamsite. All of them are solid-state OBs. Their main combat mode is aerosol (smoke or fog). Agents cause irritation to the eyes and respiratory system, and differ from each other only in terms of their effects on the body. In low concentrations, CS simultaneously has a strong irritant effect on the eyes and upper respiratory tract, and in high concentrations it causes burns to exposed skin. In some cases, paralysis of the respiratory organs, heart and death occurs. Chloroacetophenone, acting on the eyes, causes severe lacrimation, photophobia, pain in the eyes, convulsive compression of the eyelids. If it comes into contact with the skin, it may cause irritation and burning. Adamsite, when inhaled after a short period of latent action (20-30 s), causes a burning sensation in the mouth and nasopharynx, chest pain, dry cough, sneezing, and vomiting. After leaving the contaminated atmosphere or putting on a gas mask, signs of damage increase within 15-20 minutes, and then slowly subside over 1-3 hours.

All of these irritating agents were widely used by the US Army during the Vietnam War.

TO psychochemical agent These include substances that act on the nervous system and cause mental (hallucination, fear, depression, depression) or physical (blindness, deafness, paralysis) disorders.

These include, first of all, BZ - a non-volatile substance, the main combat state of which is aerosol (smoke). OB BZ affects the body through the respiratory system or gastrointestinal tract. When inhaling contaminated air, the effect of the agent begins to appear after 0.5 - 3 hours (depending on the dose). Then, within a few hours, there is a rapid heartbeat, dry skin, dry mouth, dilated pupils and blurred vision, unsteady gait, confusion and vomiting. Small doses cause drowsiness and decreased combat effectiveness. Over the next 8 hours, numbness and inhibition of speech sets in. The person is in a frozen position and is unable to react to changes in the situation. Then comes a period of excitement for up to 4 days. It is characterized by increased activity in the affected person, fussiness, erratic actions, verbosity, difficulty in perceiving events, contact with him is impossible.. This lasts up to 2-4 days, then there is a gradual return to normal.

All chemical munitions have approximately the same structure and consist of a body, an explosive device, an explosive device and a bursting charge. To use explosive agents, the enemy can use aerial bombs, artillery shells, airborne discharge devices (VAP), as well as ballistic cruise missiles (UAVs). It is believed that with their help it is possible to transfer a significant amount of toxic substances to the target and at the same time maintain the surprise of the attack.

Modern aviation has exceptionally great capabilities for the use of chemical agents. An important advantage of aviation is the ability to transport large quantities of explosives to targets located in the rear. Aviation means of chemical attack include chemical aviation bombs and aviation pouring devices - special tanks of various capacities (up to 150 kg).

Artillery means of using chemical agents (cannon, howitzer and rocket-propelled chemical ammunition) are usually equipped with sarin and VX gases. Multi-barrel rocket launchers, which compare favorably with conventional artillery, can also be used to deliver chemical agents.

In addition, chemical landmines and aerosol generators are used. Chemical landmines are buried in the ground and camouflaged. They are intended to infect areas - roads, engineering structures, passages after the withdrawal of friendly troops. Aerosol generators are used to infect large volumes of air.