Harmful substances

Every day people are exposed to thousands of different chemicals. Many are concerned about their health and are trying to find an answer to the questions: which of them are dangerous, and can they cause cancer or other problems? But we should not consider this problem only in connection with the possible impact of harmful production on the environment, as there are risks associated with malnutrition, self-medication and other behavioral factors. For example, salt food (its formula NaCl) is used daily for food. But it, in accordance with the current regulatory documents, refers to the third class of danger. And ethylene (its chemical formula C2H4) is a less harmful substance, entering into the IV class of danger. So all the same, what include concepts such as harmful substances and their classification? What documents are they installed?

The answers to these questions are given in GOST 12.1.007-77 *. Harmful substances are chemical compounds that, due to violations of safety requirements, can cause (in contact with the human body) health problems, occupational diseases or occupational injuries. All these problems are usually found already in the process of their impact or in remote periods of life and even in subsequent generations. Also, the standard sets (depending on the degree of exposure to the human body) for different chemicals contained in raw materials, intermediates, products and wastes, there are only four classes of danger. Thus, all harmful substances usually belong to extremely dangerous (1st class), highly dangerous (class II), moderately dangerous (grade III) or low hazard (grade IV).

Graduation is performed in the process of comparing actual values with standard values for specific indicators. They include the maximum allowable concentration of harmful substances (for the air of the work zone), the average lethal dose when they enter the stomach, the average lethal dose when exposed through the skin, the average lethal concentration for the air in the work area, and the coefficient of possible inhalation poisoning of acute and chronic zones actions. Thus, the hazard class of harmful substances, according to is a conditional value, which is intended for the classification of potentially hazardous chemical compounds.

Norms for MPC in the air of industrial premises and the class of their danger are specified in Appendix No. 2 to GOST 12.1.005-88 for more than 1300 titles. An even greater amount of similar information can be found in the hygiene regulations of GN 2.2.5.1313-03. It is useful to dwell on some substances, and in this connection it is appropriate to recall the negative role of improper unbalanced nutrition and the dangers of smoking (for both active and passive smokers). After all, tobacco smoke contains such harmful substances as benzapyrene, carbon monoxide, nicotine, soot and others. For comparison, it is necessary to consider the MAC and hazard classes of certain chemical compounds that enter the human body when taking medicines, with food or as a result of smoking:

• Benzopyrene - 0.00015 mg / m3, I class;
• Nicotinamide (vitamin PP) - 1 mg / m3, class II;
• Carbon black - 20 mg / d3, III class;
• Carbon monoxide (carbon monoxide) - 20 mg / d3, III class;
• Sodium chloride (edible salt) - 5 mg / m3, III class;
• Oxalic (ethanedioic) acid - 5 mg / m3, III class;
• Ethylene - 100 mg / m3, IV class.

Obviously, vitamin PP, food salt and oxalic acid are more dangerous to humans than ethylene chemical product, which is produced in large-scale production and serves as a raw material for the production of polyethylene (and it is made of film, packaging and other useful products). Special mention should be made of the dangers associated with:

1. With improper diet. A good example is oxalic acid. The maximum permissible concentration for reservoirs is 0.5 mg / dm3. It is abundant in beets (0.61%), green onions (1.48%), parsley (1.70%), spinach (0.97%), rhubarb (0.75%). Thus, if half the beet is included in the diet (the root weight is 300 g), then about 1 g of oxalic acid will enter the human body. A lethal dose, according to some sources, is 5 g when taken orally.
2. With smoking. Every six seconds, due to diseases related to smoking, one person dies in the world - this is WHO data. At the same time, there is an annual increase in mortality. It is expected that by 2020 the huge number will double and reach 10 million people a year.

It is obvious that harmful substances enter the body not only because of an unfavorable ecological situation, as it is emphasized in many media, but also because of unreasonable behavior of a person. Despite the wide opportunities for obtaining useful information, people continue to misapply, smoke, drink alcohol or drugs. Only having realized all the risks, having adjusted a balanced diet and having abandoned bad habits, it is possible to significantly reduce the effect of harmful substances on the body.