The oceans and their beaches are now home to vast numbers of tiny pieces of plastic - and the source may be your washing machine, researchers say.
Mark Anthony Browne of the University College Dublin says that so-called microplastic - bits of polyester and acrylic smaller than the head of a pin - contain potentially harmful ingredients which are consumed by animals and could be transferred to people who eat shellfish and fish.
"Ingested microplastic can transfer and persist in their cells for months," he says.
Using forensic techniques, his team examined 18 coasts around the world. They found more microplastic on shores in densely populated areas - and identified an important source as the wastewater from household washing machines.
Apaprently, more than 1,900 fibers can rinse off of a single garment during a wash cycle - it's amazing we don't all look threadbare - and Browne says these fibers are of exactly the same type as the microplastic debris found on shorelines.
"Designers of clothing and washing machines should consider the need to reduce the release of fibers into wastewater," he says.
"Research is needed to develop methods for removing microplastic from sewage and determine which fibers pose less of a problem for habitats, animals and humans."