I saw a micro blog before: the inner wall of disposable paper cup is often coated with a layer of wax. If the water temperature exceeds 40 ℃, the wax will melt, so the disposable paper cup is best filled with cold drinks. Experts suggest that when using disposable paper cups, do not drink the first glass of water, and then pour out the water after four or five minutes to make the harmful substances volatilize. Supercooled or overheated water, alcoholic or acidic drinks are not suitable for disposable paper cups.

The following is the response of netizens:

1. There are many kinds of paper cups. You should pay attention to them when purchasing.

There is a kind of material similar to the description, which is called waxing cup. However, it is not prepared for hot drinks. In addition, the wax is edible, so it's OK to eat it.

The cup for hot drinks has a polyethylene coating on the inside, so it won't happen. It can be drunk normally.

As for the harmful substances, the qualified paper cup will be fine according to the normal use. Do not use unqualified paper cups.

However, we should pay attention to many disposable paper cup workmanship is not qualified, when purchasing to pay attention to. The distinguishing criteria are good workmanship, relatively expensive price, regular product source, due marks, such as model, scope of application, QS, production date and so on. If it's a street stall, try to be careful.

2. The inner surface of waterproof paper cup is coated with polystyrene film, and there is no problem for the products produced by regular manufacturers to fill with boiling water.

3. The most common polyethylene coating Cup on the market has no wax that will melt, so cold and hot drinks are not a problem. Waxed paper cup is a cold drink cup. It is true that the wax layer will melt due to hot water, but the result is that the paper cup will seep. If it's a qualified paper cup, it's OK to drink the first cup of water. If it's a unqualified paper cup, don't drink the first cup of water.