Experiments are the only way to verify rumors. The reporter took three kinds of ordinary mobile phone cases bought from the market and found the applied chemistry laboratory of Beijing Institute of Fashion Technology to carry out scientific testing experiments.
In the first step, the experimenter put three kinds of mobile phone cases into a closed beaker, and then baked and heated them with an infrared fast dryer. If it contains toxic substances, heating can accelerate the release of toxic substances.
In the second step, the laboratory staff baked and heated the three kinds of mobile phone shells for ten minutes to increase the temperature of the mobile phone shells. This is a simulation of the microwave generated in the process of mobile phone call, and the local temperature of the mobile phone shell may be too high.
Thirdly, the volatile gases in the beaker were detected by He Xin SPIMS- 1000 online VOC mass spectrometer, and the VOC (Volatile Organic Compounds) content of these gases was analyzed.
Finally, the laboratory staff came to the conclusion that all three kinds of cheap mobile phone cases contain benzene series and formaldehyde to varying degrees. Dr. Gong Li, director of China Environmental Protection Standards Committee and associate professor of Beijing Institute of Fashion, told reporters that some inferior mobile phone cases will release toxic benzene series and formaldehyde, probably from unqualified plastic glue or adhesive. However, because there is no industrial testing standard for mobile phone cases in China, it is impossible to determine whether benzene series and formaldehyde exceed the standard.
Previously, the column group of CCTV Financial Channel "Is it true" invited the experimenters of Tsinghua University Building Environment Testing Center to conduct professional experiments. The experimenter heated the temperature of the experimental cabin to 45℃, and then put the hand case in. 1 hour later, collect the gas released by the glove box. Subsequently, the experimenters analyzed the contents of benzene and formaldehyde in these gases.
At that time, the mobile phone case was made in a 30-liter stainless steel closed cabin. Through experiments, it is found that inferior mobile phone cases will release a certain amount of formaldehyde and benzene, but the release amount is not large. The conclusions of the two scientific experiments are consistent, and the cheap mobile phone case does contain a certain amount of benzene series and formaldehyde.
Benzene and formaldehyde are both human carcinogens recognized by the World Health Organization. Benzene can be volatilized at room temperature to form benzene vapor, and the higher the temperature, the greater the volatilization. Benzene is widely used in industrial and agricultural production, and formaldehyde is also a commonly used chemical raw material. Because of its low cost, it has a good bonding effect as a resin. As for whether such volatile substances in mobile phone cases can cause cancer, there is no relevant detection standard at present.
Teilen, an engineer of Tsinghua University Building Environment Testing Center, suggested that when choosing a mobile phone case, try to choose products with no obvious odor, and try to use them in an air flowing environment to reduce the contact between children and the mobile phone case.
Benzene and formaldehyde are common chemical raw materials, mainly from building and interior decoration materials. Some pollutants will be irritating when released. Is this the standard for judging toxic gases? Teilen said that it is not reliable to judge whether there are pollutants such as formaldehyde and benzene in indoor air through intuitive feelings such as smell, tears in eyes and sore throat. The best way is to find a professional testing organization to test the indoor air condition.
Finally, experts reminded that due to the long release period of some pollutants in indoor air, in order to reduce the harm, attention should be paid to window ventilation, and adsorption materials such as activated carbon can be selected to assist in purifying indoor air.