The Te Matau a Maui waka is on a mission to find out just how much microplastic waste is in our East Coast waters.

They're on the PURE Tour (Plastics Use Resistance Education) around different parts of their ancestral waters.

"The best possible outcome is for single use plastics to be banned, that's an easy question," says waka captain Raihania Tipoki.

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Waka voyage opens eyes to NZ's ocean plastic scourge
Ocean-going waka start out for Wellington from Napier today


"Te Matau a Maui was born out of environmental kaupapa, climate change, and a lot of the impacts that are happening in the Pacific.

"It's fundamental to who we are and it just so happens that our elders from day one have been passionate about environmental kaupapa in particular to do with the moana."

Onboard with them is small team of environmental scientists from the 5 Gyres Institute based in the United States.

The 5 Gyres has studied and determined that there is 269,000 metric tonnes and 5.25 trillion particles on the ocean's surface.

"Microplastics is a problem because it impacts the food chain. They have the ability to absorb all kinds of food already in the ocean," says 5 Gyres scientist Marcus Eriken.

"They absorb the things that don't mix with water like oil drops from cars, industrial chemicals and even pesticides."

It's these toxins that find their way into the sea life and ultimately into human bellies.

"That's the pathway of pollutants from plastics into us as plastic as trash," explains Marcus.

The scientists on board the waka will trawl the ocean surface with a custom trawler made out of dense netting.

It will be dragged behind the vessel for about two to three miles and any contents it collects will be analysed by the scientists onboard.

"We are finding that there are microplastics particles as big as grains of rice or salt or pepper flakes. Small particles plague our seas.

"So this device allows us to study how many particles are there per square kilometre of the ocean.

"We'll get that research and we'll understand the impact of plastics in New Zealand waters and then better understand the impact on our fisheries, our beaches and our human health."

It is expected the tour will last for about a month with the aim to raise awareness of just how damaging plastics are to the ocean.

"It just helps to open people's eyes, as it often takes more than one experience or more than one episode for people to start thinking about this," says Raihania.

"But the momentum has already been built in terms of plastic use and our general disregard for how we treat the moana so it's just building on that momentum."

The waka will culminate its tour in Wellington with a petition against single use plastic items being handed over to Parliament.