Do you often use disposable milk tea cold drink cups when visiting outside? You may think this is "hygienic", but some low-quality milk tea cold drink cup manufacturers use fluorescent bleach and recycled polyethylene in violation of regulations, or because the process materials are not up to standard, a large number of harmful compounds will be released when they pour hot water.

Recently, reader Miss Wang reported to our newspaper that she often buys disposable milk tea cold drink cups from supermarkets or Shiduo. Due to the recent cooling of the weather, she served hot water to the guests in a milk tea cold drink cup. She noticed that when a cold milk tea cup is filled with hot water, it emits some particularly strange odors. She tried changing several brands of milk tea cold drink cups, but they all had this problem. As a last resort, she had to put some tea leaves in the milk tea cold drink cup to cover up the strange smell.

Miss Wang is very worried: does this unpleasant smell indicate that the material of the milk tea cold drink cup undergoes chemical changes under the action of hot water? Is the chemical substance released during this process toxic? She hopes that the reporter can seek confirmation from relevant experts.

With Miss Wang's question, the reporter interviewed Professor Zhang Qinfa, an expert in food packaging materials at the School of Food, South China Agricultural University.

Professor Zhang Qinfa introduced that in order to achieve water blocking effect in the production of milk tea cold drink cups, a layer of polyethylene water blocking film is applied on the inner wall. Polyethylene is the safest chemical in food processing, which is difficult to dissolve in water, non-toxic, and odorless. But if the selected material is not good or the processing technology is not satisfactory, it may oxidize to carbonyl compounds during the process of polyethylene hot melting or applying to milk tea cold drink cups. Carbonyl compounds are not easily volatile at room temperature, but when poured into hot water in a cold milk tea cup, they may evaporate, so people may smell a strange odor. Although there is currently no research to confirm how the carbonyl compounds released from milk tea cold drink cups can cause harm to the human body and lead to malignant diseases, from a general theoretical analysis, long-term intake of this organic compound is definitely harmful to the human body.

What is even more worrying is that some low-quality milk tea cold drink cups use recycled polyethylene, which will undergo cracking changes during the reprocessing process, producing many harmful compounds that are more likely to migrate into water during use. The state explicitly prohibits the use of recycled polyethylene for food packaging, but due to its low price, some small factories still use it in violation of regulations to save costs.

Professor Zhang Qinfa said that in the national standards for the quality of milk tea cold drink cups produced by manufacturers, only microorganisms need to be tested, and there is no detection of chemical substances yet, because this detection is very complex and difficult.

In addition to the problems just mentioned, some manufacturers of disposable milk tea cold drink cups buy pulp at low prices and add fluorescent bleach in the production process, which may cause cancer.

Experts say that when choosing a disposable milk tea cold drink cup, consumers should first look at the appearance and the packaging should not be damaged. Try to choose a thick and stiff milk tea cold drink cup. When purchasing, you can gently press your hands on both sides of the cup to roughly determine the stiffness of the cup body. Secondly, when looking at the logo, the product packaging should indicate the name and address of the production enterprise, the execution standard of the product, production date, expiration date, etc. Be cautious when purchasing milk tea cold drink cups with incomplete labeling. Finally, it depends on the merchant. Try to go to major shopping malls and supermarkets, and choose large enterprises that produce milk tea cold drink cups