evidence: Researchers at McGill University tested four popular brands of tea sold at grocery stores and found that a single plastic tea bag can release 11.6 billion microplastic and 3.1 billion nanoplastic particles into the water. [...] The particles come from the polypropylene that many manufacturers use to seal tea bags closed. These microplastics are found in a lot of foods and beverages (including water bottles), yet the study revealed that the levels released by the tea bags were thousands of times higher than other products. [...] First things first: Stay away from plastic tea bags. As proven by the study, those can leech potentially harmful chemicals into your drink. But even paper tea bags can have plastic particles in their sealant. So what can you buy?