The parliamentary Environment Committee has released a report on the scale, impact, and sources of plastic pollution in New Zealand’s coastal waters.
The committee initiated the briefing and is interested on how much plastic is in New Zealand coastal waters, where it comes from and what it is made of and its effects.
Fifteen organisation where invited to provide their views.
The scale of plastic pollution
The Ministry for the Environment does not hold data on the specific volumes of plastics in New Zealand coastal waters.
However, a non-profit organisation, SeaCleaners has removed 5.1 million litres of marine rubbish from our coastlines in the last 15 years.
Information from Greenpeace
The contents of a Seabin installed in Auckland’s Viaduct Basin were examined over 17 days in 2018 and every sample from the research period contained some type of plastic.
Up to 12.7 million metric tonnes of plastic went into the ocean in 2010.
The production of plastics is expected to double every 11 years.
Fisheries
Fisheries collects data on plastic accidentally caught by fishing trawler. Between 2015 and 2017 observers recorded 450 accounts of plastic.
Where does it come from?
According to the Cawthron Institute a big reason for plastic pollution is the mismanagement of accumulated plastic waste. High winds pick up plastic from open dumps for most waste.
Data collected from Sustainable Coastlines showed that 80 percent of plastics in the water come from land-based activities and 77 percent of this is from single-use plastics.
Washing of synthetic clothes and swimming in clothes made from synthetic fibres can also release microplastics into the water.
What is it made of?
According to the Cawthron Institute it is difficult to identify the polymer type and chemical additives which end up in the environment. However, microbeads, microplastics, and microfibres are found in coastal waters.
The Department of Conservation said that the most common plastics found are single use plastic, bottles, caps and lids, plastic bags and polystyrene foam.
Effects
One-third of dead seabirds and turtles have plastics in their stomachs. Plastic looks like food to marine mammals and is often intentionally ingested. After ingestion plastic can leak into animal tissue resulting in serious health effects, including reproductive disorders.
Marine species are also easily entangled in plastic products, with ropes and plastic bags doing the most harm. Entanglement can result in disease, drowning, strangulation and reduced mobility among which leaves the animal vulnerable to predators. The entanglement rate of fur seals in Kaikōura is one of the highest in the world.
Plastic rafting
Floating plastics can transport invasive species long distances across oceans which can then settle on plastic litter. Plastics will not degrade for several years and so these invasive species can be carried for a long time, threatening biosecurity.
Effect on human food supply and native flora and fauna
The Cawthron Institute stated that there is a data gap when it comes to understanding the effects of plastic pollution on flora, fauna and the human food supply.
The European Union food safety authorities are concerned about plastic in seafood.
Research completed and underway
Two scientists from the Institute of Environmental Science and Research are leading a collaborative bid to evaluate the risks of microplastics to the New Zealand environment and the food-based export economy.
Fisheries has commenced a 10-year plankton data series, which has determined the presence of plastic microfibres in samples.
Scion is leading a study which will reveal what types of plastics are found around Auckland waterways and coastlines and will provide clues to where they came from and how they were transported to the coast.