STiR coffee and tea magazine

42 STiR coffee and tea / Issue 6, 2019 (December / January 2020) By Dan Bolton T ea industry suppliers rushed to defend the publicly maligned tea bag following widespread media coverage of a research paper that revealed heat-sealed pyramid bags made of nylon and PET release billions of nanoplastic particles during a five-minute steep. "The levels of nylon and polyethylene terephthalate (PET) particles released from the teabag are several orders of magnitude higher than plastic loads previously reported in other foods," according to the McGill University study. Researchers tested leachate from teabags used by four popular supermarket teas. The peer-reviewed study, published in the journal Environmental Science & Technology, concluded that "at brewing temperature (95°C) a single tea bag releases approxi- mately 11.6 billion microplastics and 3.1 billion nano-particles into a single cup of the beverage." The Tea Association of the USA, Inc. quickly released a formal response assuring consumers "that tea brewed in tea bags is safe to consume." During the month that followed, tea brands fielded a lot of questions from concerned cus- tomers. The results were questioned by fellow scientists who posited that airborne contaminates might have raised the count (citing the non-reassuring fact that in the US up to 33% of household dust is microplastic). Critics also said that slicing open the tea bags to release the tea before test- ing might have influenced the count (but McGill's researchers pointed out that a control sample demonstrated no difference in the amount of leachate compared to uncut bags). After much media attention, including a segment on the TV program Dr. Oz, no one cred- ibly advanced the idea that exceedingly long threads of plastic polymers that break into tiny, tiny particles when heated to a boil lead to harm. But no one really knows if these very, very small micro- and nano-particles when ingested in small amounts are harmless. Ultimately the manufacturers of the films, paper, and plastic mesh used to make tea bags cleaved into two camps: one stating that while it may not be the most environmentally sustainable choice, nylon is safe and readily available at a cost well under a nickel per pyramid bag. The great majority of suppliers are deeply invested in compostable bioplastics. These plastics are at least two or three times more expensive than nylon and PET but they are viable alternatives to traditional plastics and currently favored by brands selling premium tea. Tiny Plastic Particles Tiny Plastic Particles Raise Big Concerns Raise Big Concerns Magnified view of wet nylon mesh pyramid tea bag Photo by Adobe Stock

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