Highly toxic substances: classification, characteristics

Highly toxic substances is a highly toxic chemical compound. Their danger level is determined by the degree of mass destruction of living organisms (humans, animals, plants). Poisonings mainly occur in accidents at production facilities.

Features toxic compounds

Chemicals actively used in various industries and agriculture. Poisonous substances are emitted into the atmosphere, soil or water in industrial accidents. Their toxicity and killability depend on the density of the substance and its concentration (toxic dose).

The distinctive features of highly toxic substances:

• easily carried by the wind to large areas without losing its lethality;
• toxic particles can freely penetrate into the space and buildings;
• a variety of toxic substances that differ in chemical properties, inhibits the development and production of universal individual protection;
• have a toxic effect on people direct (direct contact) and indirect (via contaminated objects) by.

Mechanisms and pathways of poisons in the human body: inhalation (through the lungs), orally (through the stomach), skin-resorbtive (through the mucous membranes and skin).

If on the human body while there are several types of toxic substances, this combined effect may enhance the overall toxic effect of the organism or, conversely, to weaken him.

Unit of highly toxic substances

Poisonous chemical substances affect the internal systems and organs with varying degrees of severity, so for each case of poisoning characterized by their symptoms.

Classification of hazardous compounds, depending on the signs of damage:

1. Suffocating. Potent asphyxiant substances affect the respiratory tract. The body's reaction to poisoning and severe lightning. Symptoms: acute nausea, suffocating cough, the feeling of helplessness and panic in his eyes. Due to acute lack of oxygen the skin gets a blue tint. In order to stop breathing just a few breaths. People die a minute later from suffocation and heart stoppage.
2. Obscheyadovitym. Poisons affect the entire body, but the main damage occurs to the respiratory system. For these poisonings are violated physiological processes – transport of oxygen by hemoglobin, cell metabolism, synthesis of biological substances. The development of the clinical picture depends on the severity of hypoxia and the degree of damage to the Central nervous system. With lightning-fast form of the person immediately loses consciousness, breathing and heart rate more frequently, there are cramps. Death occurs as a result of respiratory arrest.
3. Neurotropic. Break formation of nerve impulses, hold it on the body and transmission. They both excite and inhibit the functioning of the CNS. Symptoms – sudden weakness, headaches, mental disorders. In severe cases, blurred vision, convulsions, uncoordinated movements, involuntary urination and defecation, toxic pulmonary edema.
4. Metabolic. Poisonous substances of this group change any metabolic processes in the body. Their characteristic latent period, the symptoms some time after exposure (one week prior). Symptoms – nausea, vomiting, skin rash, itching, muscle weakness, loss of appetite. Reduced hearing, increased sensitivity to smells, loss of hair, a person rapidly loses weight, inflamed internal organs, depression. In severe cases, convulsions, coma.

Common toxic substances that are dangerous to humans

In his characterization of potent poisonous substances from different groups can have similar mechanism of human exposure.

Ammonia – a colorless gas that has a pungent smell. Have a suffocating and neurotropic action. Ammonia vapour irritates the mucous membranes of the nose and eyes, causes sunburn, which is accompanied by severe pain. In contact with the skin formed blisters and ulcers. Liquefied ammonia causes frostbite on the skin.

Hydrogen arsenic, or arsine, a colorless gas with high toxicity, no smell. When it is oxidized, the smell of garlic. The substance destroys the blood. Prolonged exposure leads to cancer development.

Hydrogen cyanide, or hydrocyanic acid, is volatile, colorless liquid with a pungent odor. Blocks the supply of oxygen to tissues, hypoxia. Disrupts Central nervous system functions, changes the parameters of respiration, slows the heart, changes the qualitative and quantitative composition of the blood.

Hydrochloric acid is a transparent liquid, corrosive, colorless. In contact with skin causes severe chemical burns 3-4 degrees. In contact with mucous membranes of the eyes leads to blindness. Inhalation of vapors irritated the respiratory tract, irritation in the throat and cough.

Hydrogen sulphide is a colourless gas with smell of rotten eggs, taste sweet. Inhalation of fumes causes headache, dizziness and nausea. In severe poisoning, the person developing seizures, pulmonary edema, coma. High concentration of hydrogen sulfide in air causes death in a single breath.

Phosgene –colorless suffocating gas, the smell of a substance reminiscent of rotten hay. Toxic only if swallowed. Has a hidden period of action up to 8 hours. Symptoms: there is a cloying taste in the mouth, nausea, vomiting. Sore throat, urge to cough. Then comes the coughing and shortness of breath, intense pressing pain in the chest, breathing is spasmodic and very frequent. In the lungs produces a lot of mucus, which makes breathing difficult. Pulmonary edema is due to filling them with blood. The weight of the body is increased 5 times. Fatal in a few days.

Chlorine – a poisonous gas that has a pungent smell and a yellow-green color. When inhaled into the lungs, causing suffocation and burns. The person experiences pain in the chest, wheezing, shortness of breath, dizziness. In severe cases, pulmonary edema, loss of consciousness.

Potent poisonous substance is a product of human activity. In nature, large concentrations of toxic substances are extremely rare. To avoid poisoning poisons, it is necessary to observe safety precautions in working with hazardous substances in the workplace, and also cautious use cleaning products.