The bottom end of each plastic product has a triangle with an arrow, which is the "recycled" symbol. There are Arabic numerals from 1-7 in it, and the different Arabic numerals represent the different properties and uses of this plastic material. Just like the identification of plastic products.
The number "1" means that the plastic material is PET, namely polyethylene terephthalate, common mineral water bottles, carbonated beverage bottles, etc., heat-resistant to 70 ℃, easy to deform, and there are substances harmful to the human body dissolved; use After 10 months, the carcinogen DEHP may be released; it cannot be placed in the car to bask in the sun, and cannot be loaded with alcohol, oil and other substances. Bottles with this logo can no longer be filled with water after use, please throw them in the recyclable trash can and let it be recycled.
The number "2" means that the plastic is made of HDPE, which is commonly used in packaging bottles for cleaning supplies and shower products. Not for use in food packaging.
The number "3" means that the material of the plastic is PVC. This material is prone to produce harmful substances at high temperatures, and even it will be released during the manufacturing process. After the toxic substances enter the human body with food, it may cause diseases such as breast cancer and birth defects in newborns. Containers of this material have been rarely used for packaging food. If in use, do not let it get hot.
The number "4" means that the material of the plastic is LDPE. The general products are cling film, plastic film, etc. The heat resistance is not strong. Usually, when the temperature exceeds 110 ℃, the qualified PE plastic wrap will appear hot melt, leaving some plastic preparations that cannot be decomposed by the human body. In addition, when the food is heated by wrapping the plastic wrap, the oil in the food can easily dissolve the harmful substances in the plastic wrap. Therefore, when the food is put into the microwave oven, the wrapped plastic wrap must be removed first.
The number "5" means that the material of the plastic is PP. High temperature resistance, more common in microwave lunch boxes. Can be reused after careful cleaning. Special attention should be paid to some microwave lunch boxes. The box body is indeed made of No. 5 PP, but the lid is made of No. 1 PE. Since PE cannot withstand high temperatures, it cannot be put into the microwave oven together with the box body. To be on the safe side, remove the lid before placing the container in the microwave.
The number "6" means that the material of the plastic is PS. More common in bowls of instant noodle boxes and fast food boxes. Resistant to heat and cold, but not in a microwave oven to avoid chemicals being released due to excessive heat. And it cannot be used to hold strong acids (such as orange juice) and strong alkaline substances, because it will decompose polystyrene that is not good for the human body, which is easy to cause cancer. Therefore, you should try to avoid packing hot food in snack boxes.
The number "7" represents the material of the plastic other than PVC and polystyrene or a composite material of various plastic materials. More common in kettles, drinking glasses, and feeding bottles. High temperature resistance, can be used repeatedly, but cannot be heated in a microwave oven.

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