Most people are familiar with the use of formalin to preserve bodies and prevent decay, but few outside of the medical field truly understand what formalin is.
What is Formalin?
Formalin, also known as formaldehyde, is a solution of formaldehyde in water (a 35%~40% solution is commonly referred to as formalin). It is a colorless liquid with corrosive properties and a strong, pungent odor due to the presence of formaldehyde. It should be noted that formalin should not come into contact with strong oxidizers, strong alkalis, phenols, urea, and other substances, as it can cause dangerous chemical reactions.
Is Formalin Harmful to the Human Body?
Formalin is a solution of formaldehyde in water, and if used properly for a short period of time, it does not cause harm to the human body. The efficacy of formalin depends on temperature and environment. Generally, at a water temperature of 23℃-26℃, the maximum safe concentration within 4 hours is 56ppm. Typically, we use a concentration of 30ppm, which does not cause harm to the human body.
Pharmacological Effects of Formalin
The main pharmacological effect of formalin is to inhibit the synthesis of nuclear proteins, suppress cell division, and harmonize the nucleus and cytoplasm of cells, ultimately causing microorganisms to die. Therefore, it is often used for the preservation of bodies in laboratories to prevent decay.
Uses of Formalin
1. When the water temperature of formalin is around 28℃, its efficacy has a bactericidal effect on swollen planktonic organisms. Therefore, formalin has a certain preservative function and is commonly used for the preservation of bodies in laboratories.
2. Formalin is mainly used as a dyeing auxiliary and resin finishing agent to improve wrinkle resistance and dimensional stability in textile products.
3. Formalin also has a certain role in fish farming. When diluted in water, it can activate tired fish and make them more active.
Hazards of Formalin
Although formalin is not harmful to the human body in the short term, its main component is formaldehyde, which can cause certain harm with long-term exposure.
If the human body comes into contact with formalin, it may cause allergic reactions, dermatitis, or eczema. Formaldehyde in formalin is an irritant gas that can irritate the mouth, nose, and respiratory mucosa. Mild symptoms include pain and coughing, while severe cases can lead to respiratory inflammation, pulmonary edema, menstrual disorders in women, and even diseases such as nasopharyngeal cancer in newborns. Ingesting a large amount of formalin can be fatal.
In addition, scientific research and animal experiments have indicated that long-term exposure to formalin may cause cancer, and it has been classified as a "possible carcinogen."
Precautions
1. Formalin should only be used for soil and seed disinfection and should not be sprayed.
2. If precipitation occurs, it should be heated and dissolved before use. For better precipitation, a certain amount of alkali solution can be added, thoroughly mixed, and left for 2 days until the precipitation disappears before use. When using formalin with added alkali, the dilution ratio should be appropriately reduced.
