A study released by researchers at McGill University in Montreal revealed that steeping a single silky plastic tea bag at brewing temperature (95C) releases approximately 11.6 billion microplastics and 3.1 billion nanoplastics (the latter are 150 times smaller than a hair, possibly small enough to permeate human cells) made up of nylon and polyethylene terephthalate (PET) into a single cup of tea.

We suggest using loose tea and using a stainless steel mesh filter to strain out the tea leaves.  Also, use organic teas when possible, since tea leaves are sprayed with pesticides, but never washed before processing, potentially leaving pesticide residue in the tea itself.