Researchers are issuing a significant warning about microplastics found in a beverage consumed by over half of the U.S. population daily. Recent studies indicate that these tiny plastic fragments, less than 5 millimeters in size, are increasingly prevalent and have been linked to elevated risks of cardiovascular issues, cellular damage, and certain types of cancer.
The pervasive nature of microplastics has been highlighted in various studies, with particles detected in everyday items such as air dust and a substantial portion of the food supply. Experts suggest that reducing exposure is possible by avoiding plastic cooking utensils and food storage containers, particularly for reheating.
Microplastics in Tea Bags
For the estimated 159 million Americans who consume tea daily, new research published in npj Science of Food suggests that brands utilizing plastic tea bags could be a significant source of microplastic ingestion. Scientists compared brews from 14 brands using plastic tea bags against 14 brands of loose-leaf tea. When steeped for three minutes at 203 degrees Fahrenheit (95 degrees Celsius), the tea from plastic bags released between 555 and 2,498 microplastic particles per cup. In contrast, loose-leaf tea contained only .3 to 2.4 particles per cup.
The microplastics found in loose-leaf tea were a mix of materials, likely absorbed from the environment or processing. However, those identified in plastic-bagged tea were exclusively polyamide fibers, the same material used in the bags themselves, directly implicating them as the source. The study authors noted that tea bags, when in contact with hot water, become active sources of contamination, releasing thousands of microplastics and endocrine-disrupting chemicals.
Chemical Contamination Concerns
Beyond particle counts, researchers analyzed the chemicals leaching into the water. They measured Bisphenol A (BPA), known to interfere with endocrine function and impair heart activity, and phthalates, which are linked to endocrine disruption and potential cancer risks. While BPA and phthalates were detected in the bagged tea, their levels were reportedly within existing safety standards. However, the study authors cautioned that these thresholds might be outdated, especially concerning BPA, which was observed at relatively high concentrations.
"Our study found that BPA intake could reach 21.7% of [European safety limits], a finding that serves as a critical warning, particularly for vulnerable groups such as pregnant women and children," the researchers stated. They highlighted that BPA can negatively impact fetal development, as well as the physical and behavioral development of children. The study concluded that while the measured levels might appear safe according to current standards, they could be misleading, and the results do not imply an absence of risk.
Navigating Tea Brands
While the study primarily focused on tea from Turkey, the majority of tea consumed in the U.S. originates from countries such as Japan, India, Argentina, and China. Standard tea bags in the U.S. are often made from natural plant-based materials, though some brands incorporate plastic for sealing and structural integrity.
Tetley has acknowledged that its tea bags contain a small amount of plastic to ensure they remain sealed, but has stated efforts to make them 99% biodegradable. Environmental nonprofit Waste Loop reported last year that brands like Tazo, Celestial Seasonings, and Twinings have used plastic in their bags, though many are reportedly working towards becoming plastic-free. Some companies have transitioned from petroleum-based plastics to polylactic acid (PLA), a bioplastic derived from sources like cornstarch. However, research indicates that PLA bags can also shed microplastics.
For consumers seeking to minimize exposure, resources like PlasticDetox.org suggest that certain blends from Organic India, Traditional Medicinals, and Yogi use plastic-free bags. The safest option, according to experts, may be to opt for loose-leaf tea.
