Every day, people are exposed to thousands of different chemicals.Many are concerned about their health and try to answer the question: which ones are dangerous, and whether they can cause cancer or other problems?But we should not treat this problem only with regard to the possible effect of harmful production on the environment, because there are risks associated with malnutrition, medicate and other behavioral factors.For example, table salt (the formula her NaCl) is used daily in food.But it is in accordance with existing regulations, it relates to a hazard class III.A ethylene (its chemical formula C2H4) is a substance less harmful within the hazard class IV.So after all that include concepts such as the hazardous substances and their classification?What documents they are installed?
answers to these questions gives GOST 12.1.007-77 *.Harmful substances - are chemical compounds that because of violations of safety requirements can cause (in contact with the human body) health problems, occupational disease or work-related injuries.All of these problems are usually found in the course of their long-term exposure or even life periods in subsequent generations.Also standard sets (depending on the degree of impact on the human body) for various chemicals contained in raw materials, intermediates, products and wastes in all four classes of risk.Thus, all the harmful substances are usually extremely dangerous (I class), high risk (II grade), moderately hazardous (III class) or a low hazard (IV class).
gradation is made in the process of comparing the actual values with the normative values for specific indicators.These include exposure limit (for workplace air) concentration of harmful substances, the average lethal dose in contact with them in the stomach, the average lethal dose when exposed to the skin, the average lethal concentration of the air of the working area, as well as the ratio of possible poisoning by inhalation areas of acute and chronicaction.Thus, hazard class of harmful substances, according to a conditional value that is used for classification of potentially hazardous chemicals.
Regulatory MAC in the air of industrial premises and the class of danger are listed in Annex 2 to the number GOST 12.1.005-88 for more than 1,300 items.An even greater amount of similar information can be found in hygienic standards GN 2.2.5.1313-03.It is useful to highlight some of the substances, and in this regard appropriate to recall the negative role of improper unbalanced diet and the dangers of smoking (both active and passive smokers).After all, tobacco smoke contains harmful substances such as benzopyrene, carbon monoxide, nicotine, soot and others.For comparison, it is necessary to consider the MPC and the danger of certain classes of 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, II class;
- black - 20 mg / di3, III class;
- carbon monoxide (carbon monoxide) - 20 mg / di3, III class;
- sodium chloride (table salt) - 5 mg / m3, III class;
- oxalic acid (ethanedioic acid) - 5 mg / m3, III class;
- ethylene - 100 mg / m3, IV class.
Obviously, vitamin PP, salt and oxalic acid are more dangerous to human substances than the chemical is ethylene, which is produced in large scale manufacturing and serves as a raw material for production of polyethylene (and from there to make the film, container and other useful products).Emphasis should be placed on the dangers of:
- malnutrition.An illustrative example - oxalic acid.MPC for water bodies is equal to 0.5 mg / dm3.It contains a lot of beets (0.61%), green onions (1.48%), parsley (1.70%), spinach (0.97%), rhubarb (0.75%).Thus, if a half ration include beet (root weight 300 g), the human body gets about 1 g of oxalic acid.Lethal dose, according to some, is considered to be 5 g ingestion.
- smoking.Every six seconds due to diseases related to smoking in the world dies of one man - a WHO data.This annual increase observed mortality.It is expected that by 2020, a huge number will double and reach 10 million. Per year.
obvious that harmful substances enter the body, not only due to unfavorable environmental conditions, as highlighted in many media, but also because of unreasonable behavior.Despite the opportunities for obtaining useful information, people continue to eat properly, smoke, use alcohol or drugs.Only having realized all the risks by setting up a balanced diet and giving up bad habits, can greatly reduce the impact of harmful substances on the body.
