Recently, a post spread wildly among WeChat friends, claiming: There are noses and eyes in the post. Is this really the case? The answer is this: newly bought clothes do need to be washed before wearing, because formaldehyde may remain on the clothes. But it is sensational to say that it will cause cancer. Is there formaldehyde on the new clothes? In fact, part of what the post said is correct. Formaldehyde is indispensable in the processing process of clothes. They are often used to remove wrinkles, preserve color and prevent corrosion. Therefore, Formaldehyde residue in new clothes is perfectly normal. According to research, Unwashed clothes, It will release 0.012-0.426 ppm of formaldehyde every day [1] (Note: ppm is a unit of concentration, Solute mass in parts per million of total solution mass). According to a CCTV report in 2014, At least more than 10 well-known brands of clothing in China have exceeded the standard of formaldehyde, and some of them have exceeded the standard by more than 40% [2]. A report by Phoenix.com in 2013 showed that 8 samples of 50 brands of children’s knitted underwear sold in the market have seriously exceeded the standard of formaldehyde, with an exceeding rate of 16% [3]. Does formaldehyde really cause cancer? In 1980, some scientists discovered through laboratory research that formaldehyde can cause nasal cancer in rats. So, can formaldehyde cause cancer in humans? In this regard, scientists have conducted a lot of research: In 2003, According to a study led by the American Cancer Institute, 25,619 workers who worked in close contact with formaldehyde, They have a higher risk of dying from leukemia than ordinary people. However, the peak formaldehyde that causes cancer is above 4.0 ppm or the average concentration is above 1.0 ppm. This is much larger than the daily release of clothes mentioned earlier [4]. In 2004, Another study conducted by the National Institute of Occupational Safety and Health tracked 11,309 workers who worked in clothing factories for more than 3 months and found that formaldehyde exposure was positively related to the risk of leukemia [5]. In 2004, the International Cancer Research Institute under the World Health Organization listed formaldehyde as a category 1 carcinogen, which is the same level as smoking [6]. Can wearing unwashed new clothes cause cancer? For new clothes, many people do not have the habit of “washing before wearing”. A survey of 11,266 people showed that only 22.8% of people will wash new clothes after buying [3]. So, does formaldehyde residue on clothes really cause cancer? There is a lot of research on formaldehyde carcinogenesis, But they are mostly concentrated on occupational exposure, At present, no one has studied whether wearing new clothes will cause cancer. Carcinogenicity is positively related to the exposure concentration and duration of carcinogens. Moreover, the nature of formaldehyde is lively and it is difficult to accumulate in the human body. The concentration and time of formaldehyde exposure caused by wearing new clothes cannot be compared with high concentration and long-term occupational exposure. Therefore, it can be speculated that the carcinogenic risk of wearing unwashed new clothes is very low. What are the formaldehyde hazards that should be paid attention to? Wear new clothes without washing. Although the risk of cancer is very low, the short-term harm caused by formaldehyde cannot be ignored. There are mainly two kinds of short-term hazards: formaldehyde irritates respiratory tract and skin, resulting in tears, dry cough, throat tingling, nausea and other reactions; Allergic reactions, Most of them are very mild rashes and itching. But it’s okay. These short-term hazards are temporary, As long as you leave formaldehyde contact in time, The body will return to normal, However, no organic damage is left. Fortunately, formaldehyde is very unstable, easy to volatilize, and dissolved in water. Therefore, it is necessary to wash new clothes thoroughly before wearing them, especially underwear and underwear that are in close contact with the body and children’s clothing. Simple cleaning can completely avoid contact with formaldehyde remaining on clothes. For clothes that cannot be washed with water, drying in a ventilated place for several days can also achieve the effect of removing formaldehyde.