"Don't Use Zip Bags Like This" ... A Chemistry Professor's Warning [Health Issue]

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\r\n[The Financial News] Many people portion food into zip bags and freeze it for storage. This is often seen as convenient and hygienic. However, depending on how they are used, the risk of exposure to microplastics can increase, so extra caution is needed.
On the 19th, Sangwook Kang, a professor in the Department of Chemistry and Energy Engineering at Sangmyung University, appeared on the YouTube channel "God of Health" and warned about harmful substances found in everyday products. Kang said, "If you seal a zip bag while the contents are still moist and then freeze it, the inner surface can stick to the food," adding, "If you open it immediately after taking it out, a large amount of microplastics may come off."
As Kang explained, opening and using a frozen zip bag right away increases the risk of microplastic exposure. Zip bags are typically made of plastic materials such as polyethylene (PE).
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\r\nPE is generally considered safe for ordinary storage, but microplastic particles can break off if it is reused several times or subjected to physical friction after heating or freezing. In particular, when food with a high moisture content is frozen in a zip bag, the moisture freezes and causes the food and the bag's surface to adhere tightly. Forcing them apart creates significant friction, making microplastic generation more likely.
Microplastics are tiny plastic fragments smaller than 5 mm. They enter the human body through food, drinking water, and air, and can cause a range of health problems.
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\r\nAccording to a paper published in Environmental Science & Technology (ES&T), microplastics are believed to affect infertility, colon cancer, reduced lung function, and chronic lung inflammation. Another study in Environmental Research also found that ingesting microplastics can trigger leaky gut and worsen inflammatory bowel disease.
To reduce the risks associated with microplastic exposure, it is important to change usage habits. Do not open a zip bag immediately after taking it out of the freezer. Instead, place it in cold water and let it thaw briefly before using it.
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\r\nKang explained, "It is better to take the frozen zip bag out first, thaw it in cold water, and then use it," adding, "If you open it in that state, the food will not stick to the walls, so you can be free from microplastics." He also said that putting hot food in a zip bag right away or repeatedly reusing a bag that has already been used should be avoided, as these practices also raise the risk of microplastic generation.
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hsg@fnnews.com Han Seung-gon Reporter