Thanks to graphic images of seals choking on plastic debris, we're more aware of keeping plastic out of the ocean, except when it comes to the plastic litter from our laundry.
Laundry? Yes. Each time you load up the washing machine, synthetic fabrics such as polyester, derived from plastic, shed microfibres that end up in the ocean via the waste water from our laundry.
Ironically, some of these fabrics have actually been manufactured from recycled plastic as a way of reducing plastic waste, only to dump it into the ocean in a different form, says Dr Mark Anthony Browne, a senior research associate with the School of Biological Earth and Environmental Sciences at the University of NSW, Australia.
It was Browne who first blew the whistle on how our laundry is polluting the ocean. In 2011 he and co-researchers discovered that the source of most plastic pollution on coastal shores sampled across the world wasn't the fragments of plastic packaging or microbeads they had expected but fabric fibres from clothing and blankets, especially acrylic, nylon and polyester.
Washing a single garment can add more than 1900 fibres to waste water, according to his research, and these fibres can potentially end up in our food.
"All pollution is a problem, but it's also a problem if we're only looking at some sources of pollution and not others. We're getting action on plastic bags, bottles and microbeads [tiny plastic particles in face scrubs and other cosmetics] but not microfibres, and it's surprising given that plastic fibres are the most abundant form of plastic contamination globally," says Brown.
"We need a strong response from the textile and the appliance industries to produce better fabrics and washing machines and from governments to improve sewage treatment and support research into developing ways to reduce microfibre pollution."
This is where I had planned to list some hints for reducing the microfibres escaping from your washing machine, like the tips available on the websites of Patagonia and Kathmandu, both companies that manufacture outdoor clothing from synthetic fabrics.
Using a front loader washing machine is one suggestion and having a special filter installed on your washing machine is another. There's also a special bag called the Guppy Friend and a gadget called a Cora Ball, which both claim to capture some of these fibres when they are used in the washing machine.
But Browne isn't convinced these measures are effective and is concerned that advice to use special bags or washing machine filters are "greenwashing" and not yet based on any solid, peer-reviewed research.
"The public needs evidence-based information about which clothes, washing machines and filters are best for reducing microfibre pollution. There's some evidence that fewer microfibres escape from front loader washing machines compared to top loaders, but we need to test multiple brands and replicate the findings to be really sure," he says.
"These environmental problems are complex and there are no simple answers."
It might help if we bought better quality synthetic clothes, and washed them less, suggests Lisa Heinze, author of Sustainability with Style, who has just completed her PhD on sustainable fashion at the University of Sydney.
"Better quality fabrics have longer fibres that don't break down and are more tightly woven so they don't fray or pill as rapidly as the shorter fibres in cheaper fabrics. It's an argument for buying just a few better quality clothes that you really love," she says.
"Hand washing or using the hand-wash cycle on a washing machine might help, too. The gentler you wash the better because there's less disruption to the fabric. But we often wash our clothes more frequently than we need."
This might make sense, but Browne points out that we don't yet have proof that these measures make a difference.
"At the moment there's no silver bullet to solve the microfibre problem, although there's research into producing fabrics from plant sources like kelp and grape skins that may provide the performance expected from synthetics," Lisa Heinze adds.
"But we can keep up pressure on manufacturers. Contact the brands you buy and ask them what they're doing to tackle the issue."
We could also buy more natural fibres such as cotton and wool, although they're not without their environmental issues either, especially cotton.
"It can take up to 3800 litres of water to produce one kilo of cotton fibre," Heinze says, "and growing cotton that's not organic takes up 25 per cent of the world's pesticides."