1. Generally speaking, plastic bags with pungent smell use the recycled materials of waste plastics and contain a large number of colorants, which can cause cancer and can not be used to hold food.

2. See if there is a "food" sign on the appearance. Generally, the mark shall be on the front of the packaging bag in a conspicuous place.

3. Put the plastic bag in the sun or light to see if there are black spots and holes. Plastic bags with impurities must use waste plastics as raw materials.

4. Touch the surface of the plastic bag with your hand. It is very smooth and non-toxic. If the color is mixed, and the touch is sticky and astringent, it is toxic.

5. Put the plastic bag in the water and press it to the bottom by hand. Wait a moment, the non-toxic plastic bag will emerge from the water and the toxic plastic bag will sink to the bottom.

6. Because the plasticizer is added to the plastic bag, it is very harmful to the human body. In life, we should put the ingredients into the refrigerator. We can use fresh-keeping film instead! If you feel that the plastic wrap is troublesome, the special refrigerator food storage box will certainly help you, which is healthy and convenient.