Is the heating of plastic electric lunch box harmful to human body?

Whether it is harmful or not depends on the materials used. There is a number at the bottom of each plastic container (it is a triangle with an arrow, and there is a number in the triangle). "1" PET mineral water bottles and carbonated beverage bottles can recover hot water: heat resistance is 65℃, cold resistance is -20℃, and they are only suitable for warm or frozen drinks. They are easy to deform when filled with high-temperature liquid or heated, and some substances harmful to human body are melted out. Moreover, scientists have found that after 1 plastic products are used 10 months, DEHP, a carcinogen, may be released, which is toxic to testicles. Therefore, drink bottles should be thrown away when they are used up. They should not be used as drinking cups or as storage containers for other items, so as not to cause health problems. "No.2" HDPE cleaning products and bath products are not thoroughly cleaned. Recycling is not recommended: it can be reused after careful cleaning, but these containers are usually not easy to clean, and the original cleaning supplies remain and become a hotbed of bacteria. You'd better not recycle them "No.3" PVC is rarely used in food packaging at present, so it is best not to buy it: this material is easy to produce harmful substances at high temperature, and even released during the manufacturing process. Toxic substances entering the human body with food may cause diseases such as breast cancer and birth defects of newborns. At present, containers made of this material are rarely used for packaging food. If it is in use, don't let it get hot. "No.4" LDPE cling film, plastic film and other cling films are wrapped on the surface of food and put into microwave oven for use: the heat resistance is not strong. Usually qualified PE plastic wrap will melt when the temperature exceeds 1 10℃, leaving some plastic preparations that cannot be decomposed by human body. Moreover, food is wrapped and heated with plastic wrap, and the oil in food can easily dissolve the harmful substances in plastic wrap. Therefore, before putting food into the microwave oven, you must first remove the wrapped plastic wrap. "No.5" PP microwave lunch box and fresh-keeping box generally use PP special for microwave oven (polypropylene, which can resist high temperature 120℃ and low temperature -20℃). For cost reasons, lids are generally not used. When put into the microwave oven, the cover must be removed before use. Because all kinds of bayonet fresh-keeping boxes use transparent PP instead of special PP, they can't be put into the microwave oven. Usage: The only plastic box that can be put into the microwave oven can be reused after careful cleaning. It should be noted that some microwave lunch boxes are indeed made of No.5 PP, but the lid is made of No.0/kloc-PET. Because PET is not resistant to high temperature, it can't be put into the microwave oven with the box. To be on the safe side, open the lid before putting the container in the microwave oven. "No.6" PS bowl-packed instant noodle box and snack box should not be cooked in microwave oven: it is heat-resistant and cold-resistant, but it cannot be put in microwave oven to avoid releasing chemicals when the temperature is too high (it will be released when the temperature is 70℃). And it cannot be used to load strong acids (such as orange juice) and strong alkaline substances, because it will decompose polystyrene which is unfavorable to human body and easy to cause cancer. Therefore, you should try to avoid packing hot food in fast food boxes. Other types of "No.7" PCs: PC glue for kettles, cups and bottles is used when heated to release bisphenol A: This material is widely used, especially in bottles, and it is controversial because it contains bisphenol A. Lin Hanhua, an associate professor in the Department of Biochemistry of City University of Hong Kong, said that in theory, as long as bisphenol a 100% is converted into plastic structure in the process of manufacturing PCs, it means that the products are completely free of bisphenol A. However, if a small amount of bisphenol A is not converted into the plastic structure of PC, it may be released into food or drink. Therefore, when using this kind of plastic container, we should be especially careful.