Need to do more to reduce plastic pollution in water

1 July 2022

New Zealanders are amongst the highest generators of plastic waste in the world and on top of this there is now concern about the level of microplastics in our water.

As Plastic-free July gets underway, Water New Zealand chief executive Gillian Blythe says while the recent move to ban many single-use plastics is an important step towards reducing pollution in our waterways, there is an urgent need to do much more.

She says microplastics are a growing concern.

“Plastic fragments from many household products end up being washed down our kitchen and bathroom sinks and laundry pipes, to wastewater treatment plants.

“A lot of microplastic pollution comes from everyday things such as synthetic clothing and furnishing, glitter, sponges, plastic bottles, cosmetics, cleaning products and so on.

“Wastewater treatment plants capture a significant amount of the plastic debris, but microplastic particles – less than five millimetres – often escape through the sieving process into the environment.”

“While this is a global problem, a recent study for Aotearoa New Zealand revealed that microplastics from wastewater treatment plants are a significant contributor to coastal plastic pollution.”

The study, by Canterbury University environmental scientist, Helena Ruffell, was presented at a recent Water New Zealand conference.

It looked at both the influent and effluent of microplastics in three wastewater treatment plants in Canterbury.

Gillian Blythe says that as well as ending up in the ocean environment, microplastics are also present in biosolids which end up on the land.

“The best way to stop microplastics getting into the environment is to stop plastic pollution at source. This means using less plastic.”

She says everyone can play a role by being aware and, where possible, reducing the amount of plastic we use everyday.

“There are many changes we can all make, for instance, switching to loose leaf tea instead of tea bags, avoiding synthetic fibre wherever possible and purchasing a front-loading washing machine when you replace your current one. Front loaders have been found to shed less microfibre as well as use less water.”

It’s been estimated that New Zealanders throw away an around 159 grams of plastic waste per person every day - making us one of the world’s biggest plastic polluters on a population basis.