Formic Acid Liquid is colorless, transparent, and corrosive in appearance, and because the formaldehyde contained is highly volatile, it will emit a strong pungent smell immediately after opening the bottle. Also known as formic aldehyde, it is the simplest aldehyde. Usually, it is a combustible, colorless, and irritating gas. Soluble in water, alcohol, and ether. 35 ~ 40% formaldehyde aqueous solution is called formalin.
The use of which covers a wide range of aspects. Because formaldehyde can bind with the amino group of protein and coagulate the protein, it can be used as tissue fixative and preservative in medicine. When the concentration and dose are sufficient, this characteristic has a destructive ability on most microorganisms, so it is often used as a disinfectant.
Before medical autopsy, it should also be soaked in formalin for good preservation. If only formalin is used as a preservation solution, the concentration is 5% - 10%, and 15% can be used in some cases. The specific concentration depends on the size of the sample. In principle, the concentration of a small sample is small and that of a large sample is high. However, the commonly used preservation solution is roughly the same as the fixed solution, mainly formalin, alcohol, glycerol, and various mixtures prepared according to the proportion of these drugs. Immersion preservation is a method of preserving specimens by immersing specimens in a certain drug solution. Generally, whole materials, anatomical materials, local structures, or organs can be preserved in this way.
In medicine, the definition of formalin mostly refers to formaldehyde aqueous solution with a concentration of 35% or more than 37%. Formalin is an aqueous solution of formaldehyde and a protein coagulant. Its efficacy is related to the temperature and environment during use. When the water temperature is 23 ℃ ~ 26 ℃, the maximum safe concentration in 48 hours is 56ppm. Generally, it is harmless to spill 30ppm during actual use.
Medical experts believe that it is a chronic toxic drug. Long-term exposure to low-dose formalin will cause chronic respiratory diseases, female menstrual disorders, neonatal physical decline, and even nasopharyngeal carcinoma. A high concentration of formalin has toxic effects on the nervous system, immune system, and liver.
Many scientific studies and animal experiments have long pointed out that long-term exposure to formalin may lead to cancer, which has been listed as a "suspected carcinogen". Trace formaldehyde metabolizes rapidly in the human body, and its residue is not strong. About 35% can be metabolized into formic acid, which is discharged in the form of formates in urine, and the remaining 65% can continue to be metabolized into carbon dioxide and water, However, the biggest problem is that it may cause cell degeneration, and the gene mutation test of bacteria, human isolated cells or animal cells is positive, and the possibility of causing biological malformation cannot be ruled out.