Tea bags & microplastics

We’ve always used Co-op fair trade loose tea, but relented and used their tea bags when camping.
My gran always said tea bag were made from sweeping up’s so that was drilled into me as a child.

We visited a tea  plantation and tea factory in Sri Lanka and one of the group told the tea man - much the same thing. The tea man laughed and said that all the sweepings go to the British supermarkets!! I "think" he was joking.