To put plastic bags under the bottom of the water, because of different specific gravity, polyethylene, polypropylene floating on the surface is non-toxic, polyvinyl chloride, polystyrene sink under the bottom is toxic.
From the appearance of polyethylene, polypropylene is relatively soft, basic transparent, but polyethylene milky white, polypropylene, and PVC plastic bag slightly yellow, softer than polyethylene, polypropylene, and slightly plasticizer flavor.
Non-toxic raw materials polypropylene, polyethylene, hand touch has a sense of lubrication, surface image with wax, flammable, like candlestick oil dripping, flame yellow, paraffin smell, this can be installed food. Such as the use of toxic raw materials PVC, polystyrene, melamine plastic bag hand trigger adhesion, not easy to burn, from the fire is extinguished, the flame is green, has the smell of choking nose, can not be used to install rice, food and so on.
In addition, you can also do this:
1. Jitter detection method: In the purchase of things, you can first grab one end of the plastic bag with your hands, shake hard a few times, if the plastic bag issued a crisp sound is non-toxic, if the sound is stuffy is toxic.
2. Hand-Touch Detection method: You can touch the plastic bag by hand, if it is non-toxic plastic bag will have a sense of lubrication, indicating that it is non-toxic, feel a sticky feeling, indicating that this plastic bag is poisonous.