Beneficial harmful phenol. Negative effects of phenol on humans

Formed on the basis of benzene. Under normal conditions, they are solid toxic substances with a specific aroma. In modern industry, these chemical compounds play an important role. In terms of volume of use, phenol and its derivatives are among the twenty most popular chemical compounds in the world. They are widely used in the chemical and light industries, pharmaceuticals and energy. Therefore, the production of phenol on an industrial scale is one of the main tasks of the chemical industry.

Phenol designations

The original name of phenol is carbolic acid. Later, this compound was given the name “phenol”. The formula of this substance is shown in the figure:

The phenol atoms are numbered from the carbon atom that is connected to the OH hydroxo group. The sequence continues in such an order that the other substituted atoms receive the lowest numbers. Phenol derivatives exist in the form of three elements, the characteristics of which are explained by the differences in their structural isomers. Various ortho-, meta-, para-cresols are only a modification of the basic structure of the compound of the benzene ring and hydroxyl group, the basic combination of which is phenol. The formula of this substance in chemical notation looks like C 6 H 5 OH.

Physical properties of phenol

Visually, phenol appears as solid, colorless crystals. In open air they oxidize, giving the substance a characteristic pink tint. Under normal conditions, phenol is quite poorly soluble in water, but with an increase in temperature to 70 o this figure increases sharply. In alkaline solutions this substance is soluble in any quantity and at any temperature.

These properties are also preserved in other compounds, the main components of which are phenols.

Chemical properties

The unique properties of phenol are explained by its internal structure. In the molecule of this chemical substance, the p-orbital of oxygen forms a single p-system with the benzene ring. This tight interaction increases the electron density of the aromatic ring and decreases this indicator for the oxygen atom. In this case, the polarity of the bonds of the hydroxo group increases significantly, and the hydrogen included in its composition is easily replaced by any alkali metal. This is how various phenolates are formed. These compounds do not decompose with water like alcoholates, but their solutions are very similar to salts of strong bases and weak acids, so they have a fairly pronounced alkaline reaction. Phenolates react with various acids; as a result of the reaction, phenols are reduced. The chemical properties of this compound allow it to react with acids, forming esters. For example, the reaction of phenol and acetic acid leads to the formation of phenyl ester (phenyacetate).

The nitration reaction is widely known, in which, under the influence of 20% nitric acid, phenol forms a mixture of para- and orthonitrophenols. When phenol is treated with concentrated nitric acid, it produces 2,4,6-trinitrophenol, which is sometimes called picric acid.

Phenol in nature

As an independent substance, phenol is found in nature in coal tar and in certain types of oil. But for industrial needs this quantity does not play any role. Therefore, obtaining phenol artificially has become a priority for many generations of scientists. Fortunately, this problem was resolved and artificial phenol was eventually obtained.

Properties, receiving

The use of various halogens makes it possible to obtain phenolates, from which benzene is formed upon further processing. For example, heating sodium hydroxide and chlorobenzene produces sodium phenolate, which, when exposed to acid, breaks down into salt, water and phenol. The formula for such a reaction is given here:

C 6 H 5 -CI + 2NaOH -> C 6 H 5 -ONa + NaCl + H 2 O

Aromatic sulfonic acids are also a source for the production of benzene. The chemical reaction is carried out by simultaneously melting alkali and sulfonic acid. As can be seen from the reaction, phenoxides are formed first. When treated with strong acids, they are reduced to polyhydric phenols.

Phenol in industry

In theory, the simplest and most promising way to obtain phenol looks like this: with the help of a catalyst, benzene is oxidized with oxygen. But until now, a catalyst for this reaction has not been selected. Therefore, other methods are currently used in industry.

A continuous industrial method for the production of phenol consists of the interaction of chlorobenzene and a 7% sodium hydroxide solution. The resulting mixture is passed through a one and a half kilometer system of pipes heated to a temperature of 300 C. Under the influence of temperature and maintained high pressure, the starting substances react, resulting in 2,4-dinitrophenol and other products.

Not long ago, an industrial method for producing phenol-containing substances using the cumene method was developed. This process consists of two stages. First, isopropylbenzene (cumene) is obtained from benzene. To do this, benzene is alkalated with propylene. The reaction looks like this:

After this, cumene is oxidized with oxygen. The output of the second reaction is phenol and another important product, acetone.

Phenol can be produced on an industrial scale from toluene. To do this, toluene is oxidized on oxygen contained in the air. The reaction occurs in the presence of a catalyst.

Examples of phenols

The closest homologues of phenols are called cresols.

There are three types of cresols. Meta-cresol under normal conditions is a liquid, para-cresol and ortho-cresol are solids. All cresols are poorly soluble in water, and according to their chemical properties they are almost similar to phenol. IN natural form Cresols are found in coal tar and are used industrially in the production of dyes and some types of plastics.

Examples of diatomic phenols include para-, ortho-, and meta-hydrobenzenes. All of them are solids, easily soluble in water.

The only representative of trihydric phenol is pyrogallol (1,2,3-trihydroxybenzene). Its formula is presented below.

Pyrogallol is a fairly strong reducing agent. It oxidizes easily, so it is used to produce oxygen-free gases. This substance is well known to photographers; it is used as a developer.

Phenols are organic compounds that can cause harm to humans and affect their health. Despite this, the production of this substance in the world increases every year.

Characteristics of phenols

Physical properties phenol: their shape resembles crystals, which tend to oxidize in air, turning pink, and has a specific odor similar to the smell of gouache. The maximum permissible concentration (MPC) of phenol in the air is 4 mg/m³, in natural reservoirs – 0.001.

This substance dissolves well in alcohol, oils, and acetone. Phenol dissolves in water gradually, in a ratio of 1/20 if the water temperature reaches +700° C. In polluted natural waters, its content can reach tens and even hundreds of micrograms per liter.

Carbolic acid is a 2-5% solution of phenol and is an excellent antiseptic that can destroy pathogenic microbes and bacteria. Carbolic acid is used in the production of many pharmaceuticals.

Synthetic technical phenol is used as a raw material for the production of caprolactam, adipic acid, aniline, alkylphenol, and hydroquinone. In terms of the number of OH groups, phenols and alcohols are similar in structure, but phenol is a stronger acid.

Application in medicine and other industries

The scope of phenol, due to its danger and toxicity, is limited. To reduce the danger, it is used in small quantities and mixed with other components. The substance is actively used by manufacturers in the following industries:

• Medicine: used as a good antiseptic, disinfectant against fungal infections, inflammation of the middle ear. It is also involved in the manufacture medicines(Aspirin), in genetic engineering;
• In cosmetology: phenol peeling. Phenol formaldehyde is used for the manufacture of cosmetic products;
• Oil refining industry: purification of residual oil raw materials;
• Agriculture: various fertilizers to control pests and weeds. Also used as an antiseptic for disinfecting animal skins;
• Food industry – for food preservation;
• Chemical industry: production of cleaning and disinfectants, epoxy resins, plastics, in the production of dyes.

Why is phenol dangerous?

This substance is dangerous and toxic, its hazard class is second. It penetrates the body through mucous membranes and skin, after which it is transported to internal organs:

• The entry of one gram of phenol into the human body leads to fatal outcome. Less than one gram is enough for a child's body. Regardless of the state in which phenol formaldehyde is found, it is a colossal harm for humans that affects health;
• Liquid phenol or in the form of vapor (gaseous) can cause burns or allergic reactions, and also causes tissue necrosis (as a result of changes in protein molecules).
• In addition, they impair blood circulation in the body, destroy red blood cells, and provoke the occurrence of dermatitis.

To avoid occurrence severe consequences phenol formaldehyde on the body, you need to know the causes of poisoning and ways to combat it.

Causes of poisoning

Poisoning occurs for the following reasons:

1. Use of phenol-containing medications whose expiration date has expired;
2. Ignorance of the composition of the medicine, use without a “prescription”;
3. Phenol poisoning upon contact with toys (most often found in toys made in China, although other manufacturers also suffer from this problem.
4. Excessive dosages.

If adults fall under the influence of phenol through carelessness, then children suffer due to the fact that adults put the medicines in easily accessible places, and sometimes even left them open.

Symptoms of poisoning

Phenol poisoning is divided into acute and chronic.

Acute poisoning occurs when the substance comes into contact with the skin, orally, or when vapors are inhaled. It is very difficult to be poisoned by vapors at home; this happens much more often in enterprises. One breath is enough to observe the following symptoms:

• Persistent cough caused by irritation of the lungs;
• Excessive excitability;
• Severe pain in the head;
• Weakness and body aches.

The above health problems may cause hospitalization.

Signs of phenol poisoning upon contact with skin:

• The damaged area of ​​the skin becomes white;
• Skin transformation, appearance of wrinkles and folds;
• After a while, the skin turns red;
• Bubbles are blown;
• Burning and tingling.

If the chemical gets ingested, the following symptoms may occur:

• Bad breath;
• The appearance of spots in the oral cavity;
• Pain in the throat, internal organs;
• Feeling unwell, vomiting;
• Increased sweating;
• Change in urine color.

Large doses of carbolic acid can cause death.

In the case of constant but small exposure to the substance on the body, chronic poisoning develops, which is accompanied by:

• Weakness and body aches;
• Poor sleep;
• Severe headache;
• Lack of appetite;
• Bad mood.

First aid for phenol poisoning

If you suspect phenol poisoning, you should immediately seek medical help. It is impossible to remove the substance from the body on your own, but providing first aid is quite possible.

1. Take the victim to fresh air;
2. If the concentration of the substance in the stomach is high, you should take the sorbent with plenty of water;
3. In case of internal poisoning, you need to rinse your mouth thoroughly with water (milk) for 5 - 10 minutes, then spit;
4. Damaged skin should be washed with water;
5. Do not leave the shower until the ambulance arrives, thoroughly rinse all affected areas of the body.

Full treatment and diagnosis are carried out only under the supervision of a doctor. The poison should be removed using vitamin B1, ethanol (externally), as well as through procedures such as tracheotomy and intubation.

Prevention

The basic rule that must be followed to avoid poisoning is to avoid contact with the substance when working with phenol-containing components. It is recommended to use protective equipment (gloves, masks, suits and respirators).

Do not buy medications that contain phenol formaldehyde; if possible, take analogue and alternative medications (it’s easier to spend a little money than risk your health); if you have them at home, store them in places that are difficult for children to reach.

For cosmetic purposes, I use phenol formaldehyde as a phenol peeling, but it can exhibit an allergic effect, so it is worth thinking about the advisability of such a procedure.

Phenol is an organic chemical substance, a hydrocarbon. Other names: carbolic acid, hydroxybenzene. It comes in natural and industrial origin. What is phenol and what is its significance in human life?

Origin of the substance, chemical and physical properties

The chemical formula of phenol is c6h5oh. By appearance the substance resembles crystals in the form of needles, transparent, with a white tint. In the open air, when exposed to oxygen, the color becomes light pink. The substance has a specific odor. Phenol smells like gouache paint.

Natural phenols are antioxidants that are present in varying quantities in all plants. They determine color, aroma, and protect plants from harmful insects. Natural phenol is beneficial for the human body. It is contained in olive oil, cocoa beans, fruits, nuts. But there are also toxic compounds, such as tannin.

The chemical industry produces these substances through synthesis. They are poisonous and very toxic. Phenol is dangerous for humans, and its industrial scale production significantly pollutes the environment.

Physical properties:

• Phenol dissolves normally in water, alcohol, alkali;
• has a low melting point, at 40°C it turns into gas;
• its properties are in many ways similar to alcohol;
• has high acidity and solubility;
• at room temperature they are in a solid state;
• The smell of phenol is pungent.

How are phenols used?

More than 40% of the substances are used in the chemical industry to produce other organic compounds, mainly resins. It is also made from artificial fibers - nylon, nylon. The substance is used in the oil refining industry to purify oils that are used in drilling rigs and other technological facilities.

Phenol is used for the production of paints and varnishes, plastics, and in chemicals and pesticides. In veterinary medicine, farm animals are treated with the substance to prevent infections.

The use of phenol in the pharmaceutical industry is significant. It is included in many medications:

• antiseptics;
• painkillers;
• antiplatelet agents (thin the blood);
• as a preservative for vaccine production;
• in cosmetology as part of preparations for chemical peeling.

In genetic engineering, phenol is used to purify DNA and extract it from cells.

Toxic effect of phenol

Phenol is poison. In terms of its toxicity, the compound belongs to hazard class 2. This means that it is highly dangerous for environment. The degree of impact on living organisms is high. The substance can cause serious damage to the ecological system. The minimum recovery period after the action of phenol is at least 30 years, provided that the source of pollution is completely eliminated.

Synthetic phenol has a negative effect on the human body. Toxic effect of the compound on organs and systems:

1. Inhalation of vapors or ingestion damages the mucous membranes of the digestive tract, upper respiratory tract, eye.
2. If it comes into contact with the skin, a phenol burn will form.
3. With deep penetration it causes tissue necrosis.
4. Has a pronounced toxic effect on internal organs. When the kidneys are damaged, it causes pyelonephritis, destroys the structure of red blood cells, which leads to oxygen starvation. Can cause allergic dermatitis.
5. When phenol is inhaled in high concentrations, brain activity is disrupted and can lead to respiratory arrest.

The mechanism of the toxic effect of phenols is a change in the structure of the cell and, as a consequence, its functioning. Neurons (nerve cells) are the most susceptible to toxic substances.

Maximum permissible concentration (MPC of phenol):

• the maximum single dose in the atmosphere for populated areas is 0.01 mg/m³, which remains in the air for half an hour;
• the average daily dose in the atmosphere for populated areas is 0.003 mg/m³;
• the lethal dose when ingested is for adults from 1 to 10 g, for children from 0.05 to 0.5 g.

Symptoms of phenol poisoning

The harm of phenol to living organisms has long been proven. When it comes into contact with the skin or mucous membranes, the compound is quickly absorbed, overcomes the hematogenous barrier and spreads through the blood throughout the body.

The brain is the first to respond to the effects of poison. Signs of poisoning in humans:

• Psyche. Initially, the patient experiences mild excitement, which does not last long and is replaced by irritation. Then comes apathy, indifference to what is happening around, the person is in a depressed state.
• Nervous system. General weakness, lethargy, loss of strength increases. Tactile sensitivity is blurred, but the reaction to light and sounds is exacerbated. The victim feels nausea, which is not related to the functioning of the digestive system. Dizziness appears and the headache becomes more intense. Severe poisoning can lead to convulsions and unconsciousness.
• Skin. The skin becomes pale and cold to the touch, and in severe cases acquires a blue tint.
• Respiratory organs. If even small doses enter the body, a person may experience shortness of breath and rapid breathing. Due to irritation of the nasal mucosa, the victim is continuously sneezing. In case of moderate poisoning, a cough and spastic contractions of the larynx develop. In severe cases, the threat of spasm of the trachea and bronchi increases and, as a result, suffocation, leading to death.

Circumstances under which poisoning can occur are violation of safety rules when working with particularly dangerous substances, overdose of medications, household poisoning with detergents and cleaning products, as a result of an accident.

If the house contains low quality furniture, children's toys that do not meet international standards security, the walls are painted with paint not intended for these purposes, then a person constantly inhales the emanating phenol vapors. In this case, chronic poisoning develops. Its main symptom is chronic fatigue syndrome.

Principles of first aid

The first thing to do is to interrupt human contact with the poisonous source.

Take the victim out of the room into fresh air, unfasten buttons, locks, and zippers to better ensure access to oxygen.

If the phenol solution gets on your clothing, remove it immediately. Rinse the affected skin and mucous membranes of the eyes thoroughly and repeatedly with running water.

If phenol gets into the mouth, do not swallow anything, but immediately rinse your mouth for 10 minutes. If the substance has managed to enter the stomach, you can drink the sorbent with a glass of water:

• activated or white carbon;
• enterosorb;
• enterosgel;
• sorbex;
• carbolene;
• polysorb;
• lactofiltrum.

You should not rinse the stomach, as this procedure will increase the severity of the burn and increase the area of ​​damage to the mucous membrane.

Phenol antidote is a solution of calcium gluconate for intravenous administration. In case of poisoning of any severity, the victim is taken to the hospital for observation and treatment.

In case of severe poisoning, phenol can be removed from the body in a hospital setting using the following methods:

1. Hemosorption is the purification of blood with a special sorbent that binds molecules of a toxic substance. The blood is purified by passing through a special apparatus.
2. Detoxification therapy is an intravenous infusion of solutions that dilute the concentration of a substance in the blood and promote its natural elimination from the body (through the kidneys).
3. Hemodialysis is indicated in severe cases where there is a potential threat to life. The procedure is carried out using an “artificial kidney” apparatus, in which the blood passes through special membranes and leaves molecules of a toxic substance. Blood returns to the body clean and saturated with useful microelements.

Phenol is a synthetic toxic substance that is dangerous to humans. Even a naturally occurring compound can be harmful to health. To avoid poisoning, it is necessary to responsibly work in production where there is a risk of contact with poison. When shopping, be interested in the composition of the products. The unpleasant smell of plastic products should alert you. When using medications containing phenol, follow the prescribed dosage.

Of course phenol is a poison. Therefore, it is used as a preservative to prevent the infection from multiplying.

Phenol kills microbes, which is why it is introduced into vaccines so that they do not settle there.

Phenol is also used in cosmetics, creams, and shampoos. Phenol and its derivatives easily penetrate the human body through the skin

Even such delicious green apples do not spoil for a long time precisely because they are treated with phenol. Wash the apples thoroughly, or better yet, cut off the peel. Of course, this also applies to other fruits.

Many, many foods contain phenol.

Phenol is also contained in building materials,

in any where synthetic or plastic adhesives are used: in chipboard, fibreboard, OSB, in plywood, in thermal insulation boards, in linoleum, in laminate, a little in vinyl wallpaper, in suspended ceilings, in the plastic that is on windows, in panels PVC, in almost all of our kitchen oilcloths, etc., we live in the age of chemistry, we can’t live without it. And since our furniture is made of sawdust mixed with glue, that is, it is made of fiberboard, chipboard, MDF boards, then there is also enough of it in furniture, often even more than in building materials.

Phenol vapors are poisonous. They have a specific smell (such as the smell of gouache, since gouache contains phenol).

Some nasal and ear drops contain phenol.

Even in the human body, phenol is formed during metabolism and excreted in the urine. The mechanism is not clear to me.
Some microorganisms living in the intestines produce phenol.

It is clear that all poison and all medicine, and depends only on the dose. No one has canceled the maximum concentrations.

I don’t want to administer phenol to my child again. You always need to evaluate the benefit-harm ratio.

For example, Mantoux, Diaskintest, containing phenol, detect patients with tuberculosis. You can also do PCR. This blood or saliva is taken for analysis.
In theory, it’s probably better to do PCR. At least no bullshit is introduced into the body. I just don’t know how informative it is, and whether it is accepted as a replacement for Mantoux. I found about PCR

Order No. 64 of 02.21.2000 “On approval of the nomenclature of clinical laboratory tests” states very clearly that the Ministry of Health of the Russian Federation recommends PCR as an alternative method of testing for tuberculosis, clause 9.4.5 of the appendix. The high efficiency of this method is also stated there.

Polymerase chain reaction (PCR), based on the detection of a DNA segment characteristic only of a given pathogen, can serve as one of the methods for rapid diagnosis of tuberculosis. The high sensitivity of PCR allows you to detect single cells or even DNA fragments of the pathogen in the test material within 4-5 hours. PCR makes it possible for differential diagnosis in limited forms of tuberculosis (focal infiltrates, tuberculomas, tuberculosis of intrathoracic lymph nodes), as well as in disseminated forms of tuberculosis, in which differential diagnosis using only traditional microbiological methods is very difficult due to the rare detection of the pathogen in sputum. Summarizing the results of bacterioscopy, inoculation on solid nutrient media and PCR testing of material obtained from patients with limited forms of tuberculosis, we can conclude that the latter has a significantly higher sensitivity compared to traditional methods. PCR is highly informative when it is necessary to confirm the diagnosis of tuberculosis in children and adolescents with negative results traditional microbiological research methods. The use of PCR in the diagnosis of tuberculosis is recommended by the Ministry of Health of the Russian Federation (order No. 64 dated February 21, 2000 “On approval of the nomenclature of clinical laboratory tests”, clause 9.4.5 of the appendix).
http://www.mamakazan.ru/forum/viewtopic.php?f=80&t=15006

Although no one can give a 100% guarantee of the absence of the disease.

I don't want to make Manta anymore. A 10 year old boy has a constant positive reaction. The tuberculosis clinic diagnosed an allergy, but they didn’t stop doing Mantoux. No information content. And I'm worried. We need at least general analysis ask for blood. It will still show whether there is inflammation or not.

In general, I’m surprised why not first do a general blood test for everyone to determine whether there is inflammation. For example, with tuberculosis there is an increased content of monocytes in the blood.
Of course, an increase in monocytes can also occur in other diseases, then they can be diagnosed using other methods (diaskin test, Mantoux, PCR)

Phenols- derivatives of aromatic hydrocarbons, which may contain one or more hydroxyl groups connected to a benzene ring.

What are phenols called?

According to IUPAC rules, the name " phenol" The numbering of atoms comes from the atom that is directly bonded to the hydroxy group (if it is the senior one) and is numbered so that the substituents receive the lowest number.

Representative - phenol - C 6 H 5 OH:

The structure of phenol.

The oxygen atom has a lone electron pair at its outer level, which is “pulled” into the ring system (+M effect HE-groups). As a result, 2 effects can occur:

1) increasing the electron density of the benzene ring to the ortho- and para- positions. Basically, this effect manifests itself in electrophilic substitution reactions.

2) the density on the oxygen atom decreases, as a result of which the bond HE weakens and may tear. The effect is associated with increased acidity phenol compared to saturated alcohols.

Mono-substituted derivatives phenol(cresol) can be in 3 structural isomers:

Physical properties of phenols.

Phenols are crystalline substances at room temperature. Poorly soluble in cold water, but well soluble in hot water and in aqueous solutions of alkalis. They have a characteristic odor. Due to the formation of hydrogen bonds, they have a high boiling and melting point.

Preparation of phenols.

1. From halobenzenes. When chlorobenzene and sodium hydroxide are heated under pressure, sodium phenolate is obtained, which, after reacting with acid, turns into phenol:

2. Industrial method: the catalytic oxidation of cumene in air produces phenol and acetone:

3. From aromatic sulfonic acids by fusion with alkalis. The reaction most often carried out to produce polyhydric phenols is:

Chemical properties of phenols.

r The -orbital of the oxygen atom forms a single system with the aromatic ring. Therefore, the electron density on the oxygen atom decreases, and on the benzene ring it increases. Communication polarity HE increases, and the hydrogen of the hydroxyl group becomes more reactive and can easily be replaced by a metal atom even under the action of alkalis.

The acidity of phenols is higher than that of alcohols, so the following reactions can be carried out:

But phenol is a weak acid. If carbon dioxide or sulfur dioxide is passed through its salts, phenol is released, which proves that carbonic and sulfurous acids are stronger acids:

The acidic properties of phenols are weakened by the introduction of type I substituents into the ring and enhanced by the introduction of type II.

2) Formation of esters. The process occurs under the influence of acid chlorides:

3) Electrophilic substitution reaction. Because HE-group is a substituent of the first kind, then the reactivity of the benzene ring in the ortho- and para-positions increases. When phenol is exposed to bromine water, a precipitate is observed - this is a qualitative reaction to phenol:

4) Nitration of phenols. The reaction is carried out with a nitrating mixture, resulting in the formation of picric acid:

5) Polycondensation of phenols. The reaction occurs under the influence of catalysts:

6) Oxidation of phenols. Phenols are easily oxidized by atmospheric oxygen:

7) A qualitative reaction to phenol is the effect of a solution of ferric chloride and the formation of a violet complex.

Application of phenols.

Phenols are used in the production of phenol-formaldehyde resins, synthetic fibers, dyes and medicines, disinfectants. Picric acid is used as explosives.