The pungent smell is mainly emitted by pollutants such as formaldehyde, benzene and TVOC. Their hazards are as follows: formaldehyde is a colorless and soluble irritating gas. Wood-based panels such as particleboard, density board, plywood, adhesive and wallpaper are the main sources of formaldehyde in the air, and the release period is as long as 3 ~ 15 years. It can be absorbed through respiratory tract, and the harm of formaldehyde to human body has the characteristics of long-term, latent and concealed. Long-term inhalation of formaldehyde can cause serious diseases such as nasopharyngeal carcinoma and laryngeal cancer. Benzene is a colorless gas with a special aromatic smell. Glue, paint, coating and adhesive are the main sources of benzene in the air. Benzene and benzene series can be anesthetized by the central nervous system after being inhaled by human body; It can inhibit human hematopoietic function, reduce red blood cells, white blood cells and platelets, and increase the incidence of aplastic anemia; It can also lead to abnormal menstruation in women and congenital defects in the fetus. TVOC is the abbreviation of VOC and volatile organic compounds, and it is a heterogeneous pollutant in indoor air. Because of their low concentration and many kinds, they are generally not represented one by one, but their total amount is represented by TVOC. TVOC includes benzene, toluene, butyl acetate, ethylbenzene, p (m) xylene, styrene, o-xylene and undecane. Indoor building and decoration materials are the main sources of TVOC in the air. The research shows that even if the content of single VOC in indoor air is lower than its limit, the mixed existence and interaction of multiple VOCs will increase the hazard intensity. TVOC is toxic and irritating, which can cause the imbalance of immune level, affect the function of central nervous system, appear dizziness, headache, lethargy, fatigue, chest tightness and other symptoms, and may also affect the digestive system, such as loss of appetite, nausea, and even cause death in severe cases.
In paints and coatings, we often come into contact with some toxic compounds, which will cause certain toxic effects on the environment and human health. The common toxic compounds in paints and coatings are briefly described as follows: Toluene and xylene are moderately toxic solvents in solvent classification, which have anesthetic and stimulating effects on human body, and toxic effects on nervous system at high concentration, but their residual toxicity in human body is low, which can generally be eliminated by metabolism. The maximum allowable concentration in the air is 100mg/m3. People who have been exposed to toluene and xylene for a long time should not drink white wine, let alone excessive alcohol, because alcohol will prolong its retention time in the body and is extremely harmful to health. The workplace should maintain air circulation to reduce its concentration in the air. The latest research data show that toluene and xylene will have a certain photochemical reaction after entering the atmosphere, which will have a certain destructive effect on the ozone layer. Benzene: It is a highly toxic solvent, and a small amount of inhalation will also cause long-term harm to human body. Benzene can accumulate in the nervous system and bone marrow, causing damage to the nervous system and hematopoietic tissue and reducing the number of white blood cells and platelets in the blood. Long-term exposure can lead to leukemia. Glycol ether solvents: Glycol ether solvents will form highly toxic compounds after metabolism in the body, causing permanent damage to the blood circulation system and nervous system of human body. Long-term exposure to high concentration glycol ether solvent will cause cancer. In addition, glycol ether solvent will cause permanent damage to female reproductive system, leading to female infertility. TDI:TDI vapor pressure is low, which has a strong stimulating effect on human cornea and causes eye swelling. Inhalation of TDI vapor will damage human liver and kidney function, and long-term exposure to high concentration TDI vapor will cause cancer. In polyurethane (PU) coatings, only when the free TDI of curing agent component is less than 0.5%, it will not have toxic effect on human body. Because free TDI is not easy to escape from the system at low concentration, TDI vapor which is toxic to human body cannot be formed. In the current national standards, the content of free TDI is defined as less than 0.7% after paint mixing, so the single curing agent component is actually highly toxic. Because the domestic TDI polymerization industry is far from the developed countries, the national standard range is wide from the perspective of protecting national industries. Heavy metals: Excessive intake of heavy metals can cause chronic poisoning. Heavy metals affect children's growth and development, especially their intellectual development. Some heavy metals will remain in the brain and internal organs, causing permanent damage to the liver and kidneys. Phthalate plasticizer: This kind of plasticizer is the most widely used plasticizer in volatile coatings, which was considered harmless to human body for quite some time in the past. However, according to the latest research in Europe and America, this plasticizer has no obvious adverse effects on adult health, but it will have adverse effects on children's development, mainly causing precocious puberty in children. Therefore, in the recent European and American standards, it has been clearly stipulated that this kind of plasticizer is prohibited in children's toys. VOC:VOC is a volatile organic compound. According to incomplete statistics, China's coating industry releases about 3 million tons of volatile organic compounds into the atmosphere every year, which directly pollutes the atmospheric environment, destroys the living environment of human beings, harms human health and causes huge waste of resources, which is incompatible with the current renewable and sustainable economic model.