Marine microfibres: less plastic than predicted Marine microfibres: less plastic than predicted (Phys.org)


  Microfibers are fine strands of thread used to make clothing, carpeting and household items like mops. They are found in the air we breathe, the water we drink, and throughout the world's oceans. Natural, rather than synthetic, microfibers, though, make up the majority of those found in the ocean's surface waters—despite the fact that currently two-thirds of all human-produced fibers are synthetic.


This is based on the paper: Microfibers in oceanic surface waters: A global characterization.

They seem to assume that all the "natural" fibres (wool, cotton) are "anthropogenic" (e.g. clothing, carpeting).

Do they consider the possibility that some of the "natural" fibres may come from plants or animals without human intervention? E.g., animals shedding hair or plant fibres washed into rivers.
They don't mention it explicitly. But they don't classify further than "natural" and "synthetic". And, may I say, animal husbandry as well as agricultural use of the producers of such natural fibres (e.g. jute, wool) are under human control as well. They are introduced into the ocean via waste-water, rivers, wash from the continents.

The study used samples from surface waters, if I understand it correctly from reading superficially. They say that too many fibres are prematurely seen as "microplastic" while they may actually be natural. 

Other studies have come to the conclusion that the missing plastic-fibre in surface waters rests deeper in the water column, or may come in small(er) sizes than sampled.