Marine plastic pollution: the threat pervading Australia's waters

Disposable packaging is breaking down into tiny particles, posing a danger to marine and human life, shows research
Oliver Milman 27 Nov 13;

The waters around Australia are riddled with more than 4,000 tiny pieces of plastic per square kilometre, posing a threat to marine life and humans, new research has found.

The study, conducted by the University of Western Australia and CSIRO, found the vast majority of plastic particles were polyethylene and polypropylene, used to create disposable packaging, such as water bottles, and fishing equipment.

Researchers took seven voyages along Australia’s coastline, finding plastic concentrations were heaviest near Sydney and Brisbane, although the remote region of south-west Tasmania was also inundated with plastic, potentially swept in by the Antarctic current.

Overall, Australia is judged to have a plastic contamination level similar to the Caribbean Sea, but lower than the Mediterranean Sea. Australia, the research notes, uses nearly 1.5m tonnes of plastic a year, with only 20% of it recycled.

The study warns that plastics, if ingested by fish, “can affect the health of food webs, which include humans as an apex predator”.

Julia Reisser, lead author of the report, told Guardian Australia she was surprised to see such large quantities of plastics in Australian waters.

“Since the 1970s, we’ve been aware of the issue of plastic pollution when it comes to large vertebrae animals such as turtles and seabirds, but these particles are also affecting the little fish and plankton,” she said.

“We know that plastic is ingested by a broad range of organisms. What concerns me most is that these plastics are loaded with pollutants, such as fertilisers, because the plastic acts as a sponge for other things.

“This can be transferred via small fish to bigger fish and then us. It impacts the whole food chain. There has been research that shows toxins from plastics are causing tumours on the livers of some fish.”

Reisser said the true number of plastic particles is likely to be far higher than 4,000 pieces per square kilometre, due to the difficulty in counting extremely small pieces. Most of the particles found by Reisser measured less than 5mm across.

“The long-term solution is to decrease plastic waste, which involves the decrease in production of throwaway packaging,” she said. “Clean-up ideas are also welcome, although it won’t be a solution. There are lots of complex things that need to happen, including the Australian government helping create international laws to stop the dumping of plastics in the oceans.”

The issue of rubbish being dumped into the ocean was highlighted in October by an Australian sailor, who described parts of the Pacific Ocean as “dead” as he dodged debris for thousands of kilometres on a journey to Japan.