The NSW government has called for a national ban on the sale and production of shampoos and other products containing microplastics before they inflict worse damage on marine environments.
Environment Minister Rob Stokes said on Thursday the government would convene an industry working group intended to eliminate the pollutant by 2016.
"Anything that is manufactured that persists in the environment, we'd rather not see them there," said Martina Doblin, an associate professor at the University of Technology, Sydney.
"The environment is getting hammered by all sorts of stressors and any effort to reduce microplastics is a good thing."
Mr Stokes made the call as he released a report by the Sydney Institute of Marine Science on the scientific understanding of Sydney Harbour, which found lead contaminant levels remained so high that any activity disturbing sediment would require further investigation.
The report also identified microplastics and nanoparticles as "emerging contaminants" in the harbour that were yet to be assessed.
Other gaps in knowledge include the role of urban run-off and stormwater drains as sources of pollutants.
Shower scourge
Mr Stokes said seabirds and other marine life were at risk from the plastic micro-beads of less than 5 millimetres that are contained in personal care products such as exfoliants and shower gels that are washed down the sink into the oceans.
"Once seabirds ingest micro-particles, it can lead to blockages, choking and starvation," Mr Stokes said.
"When microplastics enter the marine environment, due to their small size and ability to float, they are unlikely to ever fully degrade."
Global environmental group Fauna & Flora International is leading a campaign to phase out microplastics as unnecessary and avoidable pollutants.
The tiny plastics often attract other toxins, such as DDT, and accumulate up the food chain, turning up in mussels and fish eaten by humans.
"Scientists around the world are worried about the health implications to humans who eat seafood contaminated by microplastics," Mr Stokes said.
Sydney Institute of Marine Science researchers examined 27 sites from the Parramatta River to Lane Cove and Port Jackson, and found the highest densities of the pollutants in Sydney's Middle Harbour
Move welcomed
Jeff Angel, executive director of the Total Environment Centre, welcomed the push towards a national ban on microplastics.
"Plastic pollution of the oceans, beaches and marine food chain damages what every Australian values about our beautiful environment," Mr Angel said. "Action does need to be taken and we call on industry to fully cooperate with Environment Minister Stokes on the micro-plastics."
Tim Silverwood, co-founder of Take 3, said a single product could contain hundreds of thousands of microplastic particles that would likely persist for decades and be ingested by a vast range of organisms.
"It's fantastic to see NSW taking a leadership role in preventing microplastic pollution," Mr Silverwood said, adding that more must also be done "to prevent the significant influx of plastic pollution originating from beverage containers, plastic bags and other packaging".
Contaminants.
The report said more than 50 per cent of the sediment in Sydney Harbour exceeded lead guidelines.
"100 per cent of the sediment exceeds trigger values [for lead] that prompt further investigation of activities that may disturb the sediment," the report said.
"The highest levels of contamination are found in the upper reaches of harbour embayments, due to small sediment size and reduced flushing."
The survey also noted that knowledge about climate change "relies solely on studies conducted in similar estuaries or on similar suites of species found within Sydney Harbour".
"This is surprising as Sydney is located in a region of the coastline that is warming at a rate much faster than the rest of the world," the report said.
Effects of climate change include the "over-wintering" in the harbour of tropical fish species brought south by the strengthening East Australian Current.
