That's an excellent page - I wish I had found that while I was browsing around. I've long been suspicious of the materials of these 'luxury' teabags (but that's probably the traditionalist in me).

EDIT: in fact, looking at this page[1], it seems they might be one of the only ones who do make a biodegradable bag ...

1. https://www.scotsman.com/read-this/is-your-favourite-tea-mad...