1. Potential Risks of Microplastics
- Recently, researchers at McGill University found that some plastic mesh tea bags commonly used by premium brands may pose safety risks. Their study was published in the American Chemical Society journal Environmental Science and Technology, focusing on four different plastic mesh tea bags. After removing the broken tea from the tea bags and placing them in water heated to 95 degrees Celsius, the researchers were surprised to find that each tea bag released about 11.6 billion microplastics and 3.1 billion even smaller nanoplastics. These values are thousands of times higher than the plastic content previously reported in other foods. Microplastics are plastic particles less than 5 mm in length, and nanoplastics are plastic particles less than 100 nanomicrometers in length, while 1 nanomicrometer is equal to one millionth of 1 mm, and the thickness of a human hair is about 75,000 nanomicrometers.
2. Sources and impacts of microplastics
- Microplastics mainly come from the manufacturing and packaging industries, but can also come from clothing fibers or microbeads (particles smaller than 1 mm, which can be added to cosmetics for exfoliation or added to medicines to make them easier to swallow). In the case of tea bags, "secondary" microplastics are produced when larger plastic fragments degrade to less than 5 mm through chemical or physical processes over time. The McGill University team believes that near-boiling water may cause more microplastics to be released into drinks. Ingestion of microplastics may have potential effects on health. Although the specific hazards are not yet fully understood, microplastics may affect the normal physiological functions of the human body after entering the human body. For example, they may carry some harmful chemicals, or accumulate in the body and affect the normal functioning of organs.
3. Different views and disputes
- Despite such research results, there are also some different views. On the one hand, some people believe that although tea bags release a large amount of microplastics in experiments, in actual daily drinking, the amount of microplastics ingested by the human body may be relatively small, and it is not certain whether it will reach the level of substantial harm to health. On the other hand, most of the current research is conducted under specific experimental conditions, which may be different from the actual tea-brewing scene. For example, factors such as the brewing time and the stability of water temperature may vary greatly in real life, which may affect the release of microplastics.
IV. Countermeasures and Suggestions
- If consumers are concerned about the safety of mesh tea bags, they can consider choosing some non-plastic tea bags, such as paper tea bags. Some high-end paper tea bags use degradable materials, which can avoid the risk of microplastic release while ensuring the convenience of tea brewing. In addition, for consumers who like traditional loose tea, brewing loose tea directly is also a good choice, which can completely avoid the microplastic risks that tea bags may bring. At the same time, relevant regulatory authorities should also strengthen supervision of tea bag production, formulate strict standards, limit the release of microplastics in tea bags, or promote tea bag manufacturers to use safer materials.
