When we drink hot or cold drinks, we usually give ourselves a lid to keep warm. Most of this lid is Ps lid , and ps is styrene. When talking about the carcinogenicity of styrene monomer, many people will cite the cancer grade evaluation of styrene by the International Cancer Research Center (IARC), saying that styrene is a category 2B carcinogen.

IRAC divides carcinogens into 5 categories. Among them, category 1 is a known human carcinogen; category 2A is likely to cause human cancer; category 2B is likely to cause human cancer; category 3 is uncertain whether it can cause human cancer; 4 The class is unlikely to cause cancer in humans. Among them, styrene monomer is included in the 2B category, which may cause cancer in humans, but the research evidence is insufficient. Also belonging to category 2B are caffeic acid, coffee, and gasoline that we are familiar with, and alcoholic beverages that we are more familiar with belong to category 1.

The current studies on the carcinogenicity of styrene are mainly used in rats raised with high doses of styrene. But in these experiments, the carcinogenic "large dose" reached tens of milligrams per kilogram of body weight, which is generally impossible for humans to reach this intake level. Moreover, styrene will cause other health hazards, such as nerve and respiratory system damage, and also requires a large dose. Therefore, the current experimental and statistical data cannot conclude that styrene is carcinogenic.

So ps lid and Paper cup sleeve can be used with confidence.