Roughly a third (by weight) of primary microplastic emissions to oceans comes simply from the laundry of synthetic textiles. "Primary Microplastics in the Ocean

Roughly a third (by weight) of primary microplastic emissions to oceans comes simply from the laundry of synthetic textiles. "Primary Microplastics in the Oceans", p. 21, https://portals.iucn.org/library/sites/library/files/documents/2017-002.pdf https://portals.iucn.org/library/sites/library/files/documen... Primary contrasts with secondary; the former is emitted directly as microplastics, the latter become microplastics by degradation of larger pieces. According to that report, "in some countries benefitting from advanced waste treatment facilities, primary microplastics releases even outweigh that of secondary microplastics." p. 5. All of which is to say, if that plastic bag is properly disposed of (and perhaps even if not), the primary concern might be to avoid synthetic fabrics. That's increasingly difficult considering that so many brands are replacing all-cotton fabrics with blends.