Formalin poisoning
Introduction
Introduction to formalin poisoning Formalin is a 35% to 40% formaldehyde solution. It is an important disinfectant and preservative. It has a strong stimulating effect on the skin and mucous membranes. It has an inhibitory effect on the central nervous system after absorption. The formaldehyde is oxidized to form formic acid in the body. , often lead to acidosis, that is, formalin poisoning. Formalin should not be exposed to strong oxidants, strong bases, phenols, urea, etc., which may cause chemical reactions. basic knowledge The proportion of illness: the prevalence rate is about 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: pneumonia, pulmonary edema, shock
Cause
The cause of formalin poisoning
Ingestion or contact with formalin (35%):
Formalin is a trade name and is commonly used in fumigation of poultry houses, hatcheries, incubators, eggs and hatchers, and shelled chicks. Inadvertent or direct contact with formalin during operation can cause formalin poisoning.
Inhalation of formalin (28%):
Its chemical composition is formaldehyde, which often causes poisoning when used improperly. It is mainly caused by the fact that the concentration of the formalin is too high or the action time is too long. Pay attention to dosage and self-protection when using.
Prevention
Formalin poisoning prevention
If formaldehyde vapor escapes during the production process, it should be sealed, formaldehyde infusion should be mechanized, and a local exhaust hood should be installed to enhance the ventilation of the workplace. The storage of formaldehyde containers should be sealed and capped.
Complication
Formalin toxic complications Complications, pneumonia, pulmonary edema, shock
Oral poisoning, severe gastrointestinal erosion, ulcers, perforation, and difficulty breathing, shock and coma, liver and kidney dysfunction.
Inhalation poisoning, severe cases of laryngeal edema, paralysis, glottic edema, a small number of pneumonia, occasionally pulmonary edema.
Formaldehyde exposure due to skin contact, eye contact, inhalation, ingestion, etc.
Symptom
Formalin poisoning symptoms common symptoms convulsions abdominal pain nausea coma diarrhea respiratory failure
After ingesting formalin, there is a burning sensation in the mouth, throat, esophagus and stomach. The oral mucosa can be seen with congestion, erosion, sick children with hooliganism, difficulty swallowing, severe abdominal pain, nausea, vomiting, diarrhea, and spit out often with blood. The stool is brown. Severe cases can cause gastrointestinal erosion, perforation, scarring of the stomach during recovery, leading to obstruction. Formalization can occur after absorption of formalin, gait sputum, acidosis, coma, shock, respiratory failure, etc. Occasionally, there is convulsion, or see liver, kidney damage, and even no urine, allergic to this product may have facial edema and bronchial asthma.
Examine
Formalin poisoning check
Determination of blood COHb:
Simple measurement methods can be used. Such as (1) addition and subtraction: take 1-2 drops of blood, dilute with distilled water 3-4ml, add 10% sodium hydroxide solution 1-2 drops, mix, increase the amount of COHb in the blood, add blood after alkali It stays reddish and the normal blood is green. The test is positive when the concentration of COHb is as high as 50%. (2) Spectroscopic examination: a few drops of blood were taken, 10 ml of distilled water was added, and a special absorption band was observed by a spectroscope.
EEG examination:
Diffuse low-wavelength slow waves can be seen, parallel to the progression of hypoxic encephalopathy.
Head CT examination:
Brain edema can be seen in the brain with a pathological density reduction area.
Diagnosis
Diagnosis and analysis of formalin poisoning
Diagnosis and differential diagnosis
According to the history of exposure to inhaled formalin, the symptoms and signs of acute central nervous system damage, combined with the results of timely measurement of blood COH, according to the Chinese diagnostic criteria (GB8781-88), can make acute formalin poisoning diagnosis, occupation Sexual formalin poisoning is mostly an accident. The contact history is relatively clear. Those suspected of living poisoning should ask about the environmental conditions at the time of the disease, such as whether the fire chimney has poor ventilation or leakage and the same person in the same room. symptom.
Diagnostic considerations
Acute formalin poisoning should be differentiated from cerebrovascular accident, concussion, meningitis, diabetic ketoacidosis and other coma caused by poisoning. Past history, physical examination, laboratory examination can help differential diagnosis, blood COHb determination It is a valuable diagnostic indicator, but the blood sample is taken early, because the COHb disappears after a few hours off the scene.
