Key Largo - Comfortable clothes are emerging as a source of plastic that's increasingly ending up in the oceans and potentially contaminating seafood, according to Gulf Coast researchers launching a two-year study of microscopic plastics in the waters from south Texas to the Florida Keys.The project , led by the Mississippi-Alabama Sea Grant Consortium, will rely partly on volunteers in coastal cleanup events. It also will expand a year's worth of data collected around Florida that predominantly found microfibres - shreds of plastic even smaller than microbeads flowing down bathroom sinks and shower drains.Smaller than microbeadsYoga pants, fleece jackets, sweat-wicking athletic wear and other garments made from synthetic materials shed microscopic plastic fibres - called "microfibres" - when laundered. Wastewater systems flush the microfibres into natural waterways, eventually reaching the sea."Anything that's nylon or polyester, like the fleece-type jackets," University of Florida researcher Maia McGuire said.When McGuire set out to study the kinds of plastic found in Florida waters, she expected to mostly find microbeads - the brightly-coloured plastic spheres the US government banned from rinse-off cosmetic products in 2015 because of the potential threat to fish and other wildlife.Instead, McGuire predominantly found microfibres, even smaller than microbeads and coming from places most people don't consider dangerous to marine life: their closets."I totally thought we were going to be finding microbeads and (bigger) fragments," McGuire said. "What do we do about it is the multimillion dollar question. The consensus seems to be that we need improvement in technology in washing machines and wastewater treatment plants to try and filter out these fibres. There's just so much we don't know."Scrubbing detergentsStudies of the Great Lakes and New York Harbour and surrounding waterways found high concentrations of plastics pollution, including microbeads. McGuire's data from Florida waters, compiled from 1 liter samples run through filters fine enough to catch microfibres missed by the trawls used in the larger studies, adds to the growing research focused on plastic pieces that degrade but never disappear.Other recent studies show that microfibres can end up in the stomachs of marine animals, including seafood such as oysters. Experts increasingly suggest that manufacturers of washing machines - not just body washes or scrubbing detergents - may need to be targeted next in efforts to reduce plastic waste in oceans.