Styrene: how dangerous and how much?

Styrene is called a colorless liquid substance, which has a specific odor that can harm a person's health. At the moment, phenylethylene, ethylene and vinylbenzene are widely used in industry mainly in the production of polymers and synthetic rubbers. Of course, at the enterprises while working with these chemicals, you should strictly follow the safety procedures.

Production of styrene

Obtain this substance in special installations (the productivity of modern can reach 150-300 thousand tons of product per year) by dehydrogenation. The reaction, as a result of which styrene is synthesized, is classified as endothermic and proceeds at a temperature of about 600-700 degrees. At the same time, an oxide iron catalyst is used with the addition of chromium and potassium. The resulting waste is processed by a multi-stage system. If the technology of use or production is violated, styrene may be released into the environment. About what it usually has consequences, we'll talk just below. First, let's look at what this substance is and what its characteristics are.

Properties

So, what is this chemical - styrene? Its properties are diverse. Consider these:

• Very poor solubility in water;
• Light oxidation;
• Rapid solubility in organic compounds;
• The ability to easily dissolve polymers;
• Polymerization to form a solid vitreous mass;
• Copolymerization with monomers;
• Addition of halogens.

To get into the human body styrene, the smell of which is very unpleasant, can both through the upper respiratory tract, and through the digestive tract. In direct contact with liquids containing it, it can be absorbed through the skin.

Styrene and the environment

The substance is quite harmful and can have a negative impact on living organisms. However, styrene in the air decomposes very rapidly. Therefore, even with emergency emissions, it can not cause special harm to nature. In the soil and groundwater, styrene decomposes into its constituent substances. The same thing happens in the air under the influence of sunlight.

Nevertheless, in most states the maximum permissible amount of this substance emitted to the environment by enterprises is regulated by law.

Rules for working with styrene

In the production of this substance and its use for the manufacture of polymers, of course, safety precautions should be followed. In most countries, the maximum permissible concentrations of styrene in the premises in which the employees of the enterprise are located are set. According to the rules, such workshops are recommended to be equipped with effective ventilation systems. Of course, employees of these enterprises should try not to inhale styrene vapor and use personal protective equipment if necessary.

It is necessary to comply with safety techniques, mixing with other substances (catalysts, peroxides, additives) styrene. Reactions conducted with violations of the manufacturer's instructions can be very violent or undesirable. Transfusion and mixing of styrene should be carried out in separate rooms, designed specifically for this purpose and well ventilated.

Polymerization of styrenes occurs even at room temperature. The danger of this process is that it can be accompanied by an explosion. Therefore, store this substance in accordance with the instructions.

Damage to styrene for the human body

Contact with this chemical can cause a person to have acute poisoning reactions, as well as chronic diseases. Virtually all organs - kidneys, liver, urinary system, blood system - can be hit by vapors of such a substance as styrene. The more dangerous this carcinogen is for a person specifically in each of these cases, in all details and will consider below. Styrene is considered to be a poison of general toxicity and relates to the 2nd class of danger. A lethal outcome for a person may result in the inhalation of air containing 10 000 mg / m ^{3 of} styrene.

What are the acute effects of styrene?

At a vapor concentration in the air in an amount of 420 mg / m ³ , people begin to show signs of irritation of the mucous membranes of the respiratory tract and eyes. When the content exceeds 840 mg / m ³ , nausea and drowsiness develop. In this case, the victim has various problems with the vestibular apparatus.

Genetic changes

Mutagenic effect is another nuisance that can trap a person who inhales styrene for a long time. What is dangerous in this respect? Judging by the research of scientists, it is possible that prolonged inhalation of styrene vapor can lead to an increase in the frequency of chromosomal structural aberrations in blood lymphocytes. Studies were conducted on workers engaged in the production of polystyrene and reinforced plastics.

Effect on the playback function

Tests conducted on rodents also suggest that inhaled styrene may have an embryotoxic effect on living organisms. However, a survey of women, workers of enterprises producing styrene, they did not reveal any special violations.

Carcinogenic action

Some studies have confirmed the fact that inhalation of styrene increases the risk of cancer of the human hematopoietic and lymphatic systems. However, this effect can only be manifested if the vapors of such substances are very long (for many years).

Admissible concentrations

So, we discussed with you what harm styrene can do to the human body. What is dangerous for this chemical product, you now understand. Of course, in those rooms where people are for a long time, the concentration of vapors of this substance should not exceed the maximum permissible standards. At factories for its production or for the production of polymers and rubbers, it must be contained in the air in an amount not exceeding:

• In the working area - 30 g / m ³ ;
• In water bodies - 0.02 g / l.

The average permissible concentration of a substance such as styrene in air is 10 mg / m ³ , daily average 0.002 mg / m ³ , single dose 0.04 mg / m ³ .

Styrene in food packaging

Unfortunately, this substance can get into the human body not only from the environment at emissions at enterprises. Polystyrene and acrylonitrile-butadiene-styrene are actively used in the production of packaging materials intended for the transport and storage of food products. It would seem that they should be completely harmless. However, as a result of the research, it was found that styrene monomer is able to migrate to food from both soft and hard packs. In some cases this substance even imparts an unpleasant aftertaste to food, milk or juice.

Used styrene, the smell of which is very unpleasant, and in the production of household items, building materials, etc.

The damage of expanded polystyrene

This material is currently one of the most popular types of insulation. You can buy it in any construction shop, and it is used very widely, including when building residential buildings. Meanwhile, expanded polystyrene is very easily degraded, decomposing for the entire service period by 10-15%. The monomer content in the decay products is at least 65%.

In addition, in the manufacture of this insulation polymerization of styrene is very rarely complete and uniform. This means that there is always a residual quantity in the granules. Therefore, styrene copolymers in any case release harmful fumes. The fact that the use of this insulator to insulate living quarters from the inside is prohibited by regulations, unfortunately, not everyone knows. In this case, it is better to use other materials. However, one should also know that styrene is also contained in the foam plastic. Since this substance is considered more harmful than formaldehyde, it is better to still insulate the houses from the inside with the use of mineral wool.

Vinyl wallpapers

Sometimes the owners of apartments do not suspect that the finishing materials used for repair contain styrene. What is dangerous for this chemical product for humans, we have already found. Therefore, it is certainly worth knowing about what materials and household items it can be. For example, a small amount of this substance is contained in vinyl wallpaper. However, unlike expanded polystyrene, this type of finishing for walls in living quarters can be used. Under normal conditions, styrene from the wallpaper is not allocated. In order that in a room covered with vinyl, its vapors appear, it is necessary to raise the temperature of the ambient air to not less than 50 degrees Celsius.

ABS plastic

Acrylonitrile butadiene styrenes are a shockproof resin used for the manufacture of automobile parts (manual controls, instrument panels, etc.), housings for household appliances (vacuum cleaners, control panels, coffee makers) and electronics (processors, monitors), furniture, sanitary ware, medical supplies , Suitcases and even children's toys.

In the ordinary state of a particular danger to human health, all these things do not represent. Styrene in its pure form begins to stand out from them only under the following conditions:

• Very strong heat.
• In medicine when used in conjunction with biomaterial.
• When using such plastics to store food. It is especially unacceptable to pour alcohol into such containers. In this case, an effect similar to heating occurs.

At present, the share of styrene polymers, including ABS, from all commercial and structural plastics is 50%.

What to do with styrene poisoning

In the event that a person has been exposed to an increased concentration of styrene vapor for a long time and has signs of poisoning, the following actions should be performed:

• Remove the injured person from the contaminated area to clean air.
• With a loss of consciousness or a very bad condition, use an oxygen mask.
• If necessary, do artificial respiration.
• Follow the temperature of the victim's body. It should not be raised or lowered.

If styrene has got on the skin or mucous membranes, extensive washing with water is necessary. The time of the procedure should be at least 15 minutes. After it is carried out, the victim must be taken to the hospital. If styrene suddenly enters the body, you must first drink a very large amount of milk or water. After this, the patient must immediately be hospitalized.

As you can see, getting styrene is a procedure that is far from harmless for non-observance of safety rules for employees. Therefore, when performing production tasks at enterprises, you should be as careful and cautious as possible. Vigilance is also worth while buying modern building materials, as well as food products in polystyrene packages.