21 Sep 2017

Is it time for an international agreement on marine plastic pollution?

From Jesse Mulligan, 1–4pm, 1:16 pm on 21 September 2017
The uninhabited Henderson Island in the South Pacific

The uninhabited Henderson Island in the South Pacific Photo: Jennifer Lavers

A new paper out this week challenges the global community to take what they've learnt from climate change agreements and apply it to plastics.

While researching the influence of plastic pollution of seabirds and marine life for her PhD, scientist Stephanie Borrelle found that even though an estimated 4-12 million tonnes of plastic makes its way into the ocean every year, there isn't much information out there about the effects.

Around the world, 346 million metric tonnes of plastic is produced every year, a large proportion of which is single-use.

This either gets washed onto coastlines or makes its way into the middle of the ocean to one of the world's five gyres (ocean garbage patches).

Agitation from the seas and sunlight breaks plastic down into smaller and smaller particles which fish and marine life mistakenly eat as food.

We don't yet know how the toxins from plastic 'bioaccumulate' in the food chain, Borrelle says.

"A small plankton might have a bit of plastic in it, then a bigger fish will eat that, then a bigger fish will eat that – so you end up with this additive effect in a lot of species. In marine mammals like whales and seabirds, we're finding high levels of toxins that are associated with plastics."

The problem of marine plastic was recognised back in the 1970s in the MARPOL agreement, but no solid work has been done towards an international agreement on plastic pollution since, she says.

"The problem is increasing and piecemeal action is never gonna be enough. We're gonna have some serious impacts on food security and human health."

Climate change and plastic pollution are intimately connected as 4 to 8 percent of oil extracted each year is made into plastic products.

The tide of the problem could be stemmed by ending fossil fuel subsidies, Borrelle says.

"Currently manufacturing of plastic is cheap enough that it doesn't account for those environmental impacts – and that's because of those subsidies. If we remove those subsidies we're not only helping climate change, we're reducing the ability of companies to manufacture as much plastic at such a cheap cost."

Developed nations also need to step up and take responsibility for 'waste colonialism', in which waste is sent to developing nations who then cop the blame for it, as well as help developing nations build infrastructure that would enable them to be less reliant on things like plastic water bottles.

It's time the global community take what's been learnt from climate change agreements and apply it to plastics, Borrelle says.

"We recognised climate change as being an issue in 1992, we recognised that plastic pollution was an issue in the '70s. So essentially we were 15 years ahead of climate change, but nothing has been put into international policy … If we continue down a similar path it's gonna be 2040 by the time anything meaningful really happens."

Get the RNZ app

for easy access to all your favourite programmes

Subscribe to Jesse Mulligan, 1–4pm

Podcast (MP3) Oggcast (Vorbis)