Ammonia poisoning: signs, consequences, diagnosis

Ammonia is considered one of the most common substances used in the chemical industry. The specific gas is used to make fertilizers, dyes, nitric acid, etc. Acute ammonia poisoning is accompanied by damage to the eyes and respiratory tract, and at high concentrations, inhalation of the gas can be fatal. Why is this compound so dangerous, and what to do to avoid unpleasant consequences of ammonia intoxication?

[ 1 ], [ 2 ]

Epidemiology

There are no special statistics on cases of ammonia poisoning. It is believed that poisoning most often occurs on an industrial scale: at enterprises that specialize in the production of explosives, paints and varnishes, refrigeration units, photoreagents, etc. The main route of penetration of the toxic substance into the body is the upper respiratory tract.

Ammonia poisoning is more common among men. This is most likely due to professional characteristics: the hazardous enterprises listed above are predominantly staffed by men.

[ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ]

Causes ammonia poisoning

The intoxication is caused by a colorless gaseous substance called ammonia, which has a specific, sharp odor. Liquefied ammonia with a concentration of 25%-30% can be purchased in some stores – it is used as a solvent.

Pure ammonia gas is used almost nowhere because of its toxicity. However, it is actively used on an industrial scale: in the production of varnishes and paints, finishing materials. No less widespread is such a medical product as ammonia. It is used in a concentration of 10% to restore consciousness in a person, to activate the gag reflex. Also, doctors sometimes use an ointment form of the drug, in which ammonia plays the role of a distracting substance in the treatment of muscle pain, neuritis, etc.

Many soil fertilizers also contain a certain amount of ammonia. The gas is used in the manufacture of refrigeration units and freezers, and in the production of explosives.

Ammonia gas is very rare for a person to encounter, but when working with ammonia-containing products, extreme caution and care should always be taken to avoid poisoning the body.

[ 8 ], [ 9 ], [ 10 ], [ 11 ], [ 12 ]

Risk factors

Ammonia poisoning can occur under the influence of the following factors:

• accidents at industrial facilities in which a gaseous substance leaks (as a rule, such accidents result in mass poisoning – both among the employees of the enterprise and among those who live or are in the surrounding area);
• the use of ammonia components in everyday life - for example, during repairs or in other circumstances;
• incorrect use of ammonia fertilizers;
• accidental inhalation or internal use of ammonia solution.

Workers who clean or inspect sewer systems are also at risk.

[ 13 ], [ 14 ], [ 15 ], [ 16 ], [ 17 ], [ 18 ], [ 19 ]

Pathogenesis

Ammonia is a final substance obtained as a result of protein metabolism processes, the metabolism of amino acids and nitrogen compounds.

Ammonia is a fairly toxic product for living beings. Therefore, most of it is converted into urea, which is much less toxic, during enzymatic transformations in the liver. Urea safely leaves the body through the urinary system, but some of it can be converted back into ammonia.

In a living organism, ammonia acts as a reducing agent and is used by the liver for the reverse synthesis of amino acids.

The gas in high concentrations or with prolonged exposure can lead to poisoning. The mechanism of this action is directly related to the ability of ammonia to corrode body tissues.

There are several ways to become poisoned by ammonia:

• inhaling gas;
• through the skin;
• through the mucous membranes.

The most common forms of ammonia poisoning are inhalation and oral ammonia poisoning.

Some people mistakenly believe that poisoning can only be caused by a concentrated substance. But this is not true: intoxication is also possible when exposed to small doses of ammonia, but over a longer period of time.

Lethal amount of aqueous solution when taken orally:

• 25-50 ml of 10% solution;
• 15 ml of 25% solution.

The maximum permissible gas concentration of ammonia in a room should not be higher than 0.02 mg per liter (20 mg per cubic meter).

[ 20 ], [ 21 ], [ 22 ], [ 23 ], [ 24 ]

Symptoms ammonia poisoning

Ammonia vapors cause severe irritation of the mucous membranes of the eyes and respiratory organs, as well as the skin. Ammonia causes severe lacrimation, eye pain, chemical damage to the conjunctiva up to loss of vision, coughing fits, hyperemia and itching of the skin.

When liquid ammonia comes into contact with the skin, it causes a burning sensation, sometimes a chemical burn with the formation of blisters and ulcers. In addition, liquefied gas absorbs some heat during evaporation, which can lead to frostbite of varying degrees.

A characteristic ammonia smell can be detected at concentrations of 37 mg/m3.

Based on its actual impact on the human body, ammonia is classified as a suffocating and neurotropic substance, which, when inhaled, causes toxic pulmonary edema and severe intoxication of the nervous system.

The first signs of poisoning are detected almost immediately after exposure to the gas:

• the appearance of a large amount of mucus in the nasopharynx, a sudden onset of a runny nose;
• weakening or loss of voice;
• secretion of tears, salivation, secretion of sweat;
• rapid breathing, coughing, sneezing;
• redness of the skin (especially on the face);
• a feeling of pressure and heaviness in the chest;
• feeling of anxiety, fear;
• chest pain;
• impaired consciousness, dizziness;
• urge to vomit;
• convulsions.

Long-term poisoning with ammonia vapors can cause severe muscle weakness and circulatory problems. Symptoms of respiratory problems may appear. If toxic exposure is repeated regularly, systemic disorders may occur: digestive problems, chronic upper respiratory tract diseases, persistent hearing loss. The victim develops edema, and the skin becomes especially sensitive.

Ammonia poisoning can be fatal if the patient develops signs of heart failure.

Poisoning with ammonia solution is possible when taken internally. In such situations, the solution can cause burn damage to the esophagus and gastric cavity, exotoxic burn shock, gastroesophageal bleeding, mechanical asphyxia due to burns and laryngeal edema. If the victim has taken highly concentrated ammonia liquid internally, reflex respiratory arrest may occur, or reactive peritonitis may develop.

Many specialists conditionally divide clinical symptoms into several degrees to make a diagnosis more quickly:

• Mild ammonia poisoning is accompanied by mucous discharge from the nose, sneezing, sore throat, hoarseness or loss of voice, pain behind the breastbone. The listed symptoms are eliminated relatively quickly, provided that the effect of ammonia on the body ceases. As a rule, doctors record the patient's clinical recovery within a week.
• In moderate ammonia poisoning, the mucous membrane of the nasal cavity swells, and burn areas form on it. The larynx also swells - this is especially noticeable in the condition of the epiglottis, arytenoid cartilages, and vestibular folds.
• In severe ammonia poisoning, extensive burn lesions of the upper respiratory tract are found: necrotic tissue is rejected. Fibrinous necrotic formations are formed in the trachea. In severe intoxication, the patient is hospitalized for at least 20 days or more.

Complications and consequences

In addition to the serious symptoms of ammonia poisoning, the development of long-term consequences of intoxication is possible. These include:

• disorders of the nervous system functionality, which are manifested by tremors, amnesia, difficulties in intellectual activity, disorientation, decreased sensitivity, dizziness;
• impairment of hearing function due to damage to the hearing organs by toxic agents;
• deterioration of vision (up to and including loss of vision).

Even if timely medical care is provided to a victim of ammonia poisoning, complications may arise in the form of neurological disorders, loss of memory of certain situations or information, and various tics. Many people experience a lower pain threshold, worsening hearing, and clouding of the lens and cornea.

When ammonia solution is taken internally, complications of a different nature develop:

• cicatricial stenosis of the esophagus;
• cicatricial stenosis of the antrum of the stomach;
• late ulcerative bleeding;
• aspiration pneumonia.

[ 25 ], [ 26 ], [ 27 ]

Diagnostics ammonia poisoning

Most often, the provoking chemical agent – ammonia – is determined by the type of industrial accident or other characteristic signs. Then the doctor can prescribe additional diagnostics – first of all, to determine the condition of the patient’s body in case of ammonia poisoning.

Blood and urine tests are mandatory for any intoxication. Toxicological testing is also carried out to establish the qualitative and quantitative composition of the toxic substance in the body's biological environments. The use of non-specific biochemical tests allows us to determine the negative impact of the toxic substance on the liver, kidneys and other organs of the victim.

Instrumental diagnostics are carried out to obtain information about the state of the victim's cardiovascular system and the functioning of the brain. The primary procedures are:

• electrocardiography;
• Ultrasound of internal organs;
• fluorography.

If necessary, procedures such as echocardiography, electroencephalography, and endoscopic examination may be prescribed.

[ 28 ], [ 29 ]

Differential diagnosis

Differential diagnostics are carried out with other possible poisonings. Depending on the situation, the doctor can take the following measures:

• check the scene of the incident;
• examine the victim's clothing;
• find out the profession and place of work;
• conduct toxicochemical studies.

The number one goal in case of poisoning is to determine the cause of the condition, since almost all treatment measures are based on the root cause.

[ 30 ], [ 31 ], [ 32 ]

Treatment ammonia poisoning

Since ammonia poisoning can be fatal in many cases, treatment should be started as early as possible. The main thing is to quickly stop the gas from affecting the body.

Prevention

Ammonia poisoning is much easier to prevent than to treat its consequences later. The main condition is to follow all the rules for safe work with chemicals. Thus, when working with varnishes, paints and solvents, you should definitely wear not only special gloves, but also glasses and a means for respiratory protection.

In the event of an industrial emergency, management must take all necessary measures to ensure the mandatory evacuation of all employees of the enterprise, as well as to block the spread of toxic gas. People must be evacuated to a sufficient distance from the emergency release zone: if this is not possible, special basement bunkers with a ventilation system installed in them should be used. The basement is a completely adequate place to protect people from exposure to ammonia: since this gas is lighter than air, it accumulates mainly closer to the ceiling and to the upper floors of the premises.

[ 33 ], [ 34 ], [ 35 ]

Forecast

The prognosis for ammonia poisoning depends entirely on how severe the toxic damage to the internal organs was. If the intoxication was mild or moderate, the prognosis can be considered favorable, with further full restoration of organ functionality within 10-25 days.

If there was severe ammonia poisoning with damage to vital organs, the recovery process can take up to several months or even years, and in some cases the pathological changes become irreversible.