plastic pollution - kaitiakitanga: April 2016

Is it time New Zealand Banned Plastic Bags?

Most checkout bags used in New Zealand supermarkets are sourced from China and Southeast Asia and are made from high-density polyethylene plastic, which is referred to as HDPE or No 2 plastic. Polyethylene is a petroleum product derived from oil – a nonrenewable resource. Plastic-bag production uses eight per cent of the world's oil. It is estimated that the petroleum energy used in one plastic bag could drive a car 11 metres. Statistics New Zealand says that in 2014, we spent $10.5 million on imported, lightweight plastic bags.

Once in landfill they do not rot, decompose or biodegrade – living microorganisms don't recognise petroleum-derived polymer as a food. It's estimated they will take up to 1000 years to break down but it's too early to test the theory. When exposed to UV rays, a lightweight plastic bag will photodegrade and break into small brittle fragments, which are toxic.

Kiwi environmental group Sustainable Coastlines says it retrieved more than 91,000 plastic bags during 34 beach clean-up events. It says sea turtles are particularly at risk – they eat jellyfish, and plastic bags floating at sea mimic that food source. In 2012 an endangered green sea turtle found dead on Motuihe Island in the Hauraki Gulf contained 58 pieces of plastic – mostly from plastic bags.
Biodegradable and compostable plastic bags are made from plant-based materials such as corn starch and wheat starch, rather than petroleum. In the right conditions, they disintegrate over time and do not leave harmful substances behind. The useful lifespan of a lightweight plastic bag is estimated as 12 minutes – from shop to car, car to kitchen, then into the rubbish.

Highly visible reusable bags at checkouts and environmental policies are fundamental for three big New Zealand retail players. Their initiatives include:
The Warehouse: Since the introduction of its Bags for Good programme in 2009 (a 10 cent charge for a lightweight plastic bag is donated to local charity), there has been a 73 per cent drop in plastic bags leaving its stores. This represents a drop from 43 million in 2008 to about 12 million in 2014.
Foodstuffs (Pak'nSave, New World and Four Square): Foodstuffs stores now use a reduced micron-HDPE checkout bag, which takes significantly less oil to manufacture than the bags used three years ago. Pak'nSave charges 10 cents a bag.
Countdown: PACK 7 is an initiative that encourages checkout staff to pack seven items in each plastic bag. Since 2006, it has reduced waste to landfill by 42 per cent. The small checkout bags used include 25 per cent recycled content.

Ban Plastic Bags in NZ

How this issue affects you, your children, our country, and our oceans world-wide:
Plastic bags impact our irreplaceable environment here in New Zealand when they are produced, when they are disposed to landfill, and especially when they are littered. Once littered, plastic bags can find their way onto our streets and parks and into our waterways. They are a large portion of the litter in our streams and can take a lifetime to fully break down. Once in the environment, plastic bags are often ingested by animals, clogging their insides which results in sickness or death, a horrible truth that is easily preventable. Other animals or birds become entangled in plastic bags and drown or can’t fly as a result. Our Ministry for the Environment also say that plastic bags exacerbate flood events when they clog pipes and block drains

Our Plastic Rubbish Killing Sea Life

At least 44 per cent of marine bird species are known to eat plastic. Last year a sperm whale calf found dead in the Aegean Sea contained all kinds of rubbish, including 100 plastic bags.
A floating plastic bag and a jellyfish look nearly identical, as do fish eggs and the tiny plastic resin pellets - nurdles - used to make plastic.
Wind and ocean currents direct rubbish that has been dumped, dropped, buried or blown out of landfills into 11 patches in the ocean, over a period of about five years.
Of these, the best known is the "great Pacific rubbish patch" in the northwest Pacific which stretches about 700,000sq km.
More than 40,000 plastic shopping bags are dumped in landfills every hour in NZ.
Cotton or hemp bags can be used thousands of times.

NZ wastes 1.6B plastic bags a year

In so-called clean green New Zealand we don't have a bag tax.
Pak'nSave introduced a charge in 1985. North Island customers pay 10c per bag while those in the South Island pay 5 cents.
The Warehouse also charge for their plastic bags. Since they started charging, they have used 67 percent fewer bags.
Kiwis use 1.6 billion bags every year – each of which is used for an average of 20 minutes.
We throw 40,000 bags into landfills every hour.
Story looks into what New Zealand should be doing to save the environment from all this plastic waste

Seabirds' Plastic Plight

The majority of seabird species are accidentally eating bits of plastic and the situation is likely to get worse,predicts a new study.Based on analysis of published studies since the early 1960s, research undertaken by CSIRO and Imperial College London has found that plastic is increasingly common in seabird’s stomachs. In 1960, plastic was found in the stomach of less than 5% of seabirds, rising to 80% by 2010. The researchers predict that plastic ingestion will affect 99% of the world’s seabird species by 2050, based on current trends.
The scientists estimate that 90% of all sea birds alive today have eaten plastic of some kind. This includes bags, bottle caps, and plastic fibres from synthetic clothes, which have washed out into the ocean from urban rivers, sewers and waste deposits. Birds mistake the brightly coloured items for food, or swallow them by accident, and this causes gut impaction, weight loss and sometimes even death.
The study, published this week in the journal PNAS, noted that the worst affected area was the Southern Ocean boundary in the Tasman Sea between Australia and New Zealand, due to its abundance of seabirds.
“For the first time, we have a global prediction of how wide-reaching plastic impacts may be on marine species – and the results are striking,” says study author Dr Wilcox, a senior research scientist at CSIRO Oceans and Atmosphere.
“This is a huge amount and really points to the ubiquity of plastic pollution.”

Threat of plastic pollution to seabirds is global, pervasive, and increasing [study mentioned in previous article]

Plastic pollution in the ocean is a global concern; concentrations reach 580,000 pieces per km2 and production is increasing exponentially. Although a large number of empirical studies provide emerging evidence of impacts to wildlife, there has been little systematic assessment of risk. We performed a spatial risk analysis using predicted debris distributions and ranges for 186 seabird species to model debris exposure. We adjusted the model using published data on plastic ingestion by seabirds. Eighty of 135 (59%) species with studies reported in the literature between 1962 and 2012 had ingested plastic, and, within those studies, on average 29% of individuals had plastic in their gut. Standardizing the data for time and species, we estimate the ingestion rate would reach 90% of individuals if these studies were conducted today. Using these results from the literature, we tuned our risk model and were able to capture 71% of the variation in plastic ingestion based on a model including exposure, time, study method, and body size. We used this tuned model to predict risk across seabird species at the global scale. The highest area of expected impact occurs at the Southern Ocean boundary in the Tasman Sea between Australia and New Zealand, which contrasts with previous work identifying this area as having low anthropogenic pressures and concentrations of marine debris. We predict that plastics ingestion is increasing in seabirds, that it will reach 99% of all species by 2050, and that effective waste management can reduce this threat.
The effect of plastic ingestion on seabirds in particular has been of concern. This concern is due to the frequency with which seabirds ingest plastic (12) and because of emerging evidence of both impacts on body condition and transmission of toxic chemicals, which could result in changes in mortality or reproduction (13 ⇓⇓–16). Understanding the contribution of this threat is particularly pressing because half of all seabird species are in decline, a higher fraction than other comparable taxa (17). Despite a recent extensive review of the threats to seabirds by a globally recognized authority (17), however, pollution has been identified only in a coastal context, and there is little mention of the impact of plastic ingestion, particularly on the high seas where the most threatened seabirds forage (17).

Our Seas Our New Zealand [has lots more info on site]

Plastic Free New Zealand is about raising public awareness about the potential threats to marine ecosystems and human health posed by millions of metric tons of plastics that pollute the world’s ocean. Pollution is one of the biggest issues facing our oceans and coasts. An estimated 4.8 to 12.7 million metric tons of plastic entered the oceans in 2010 from people living within 50 kilometres of the coast in 192 countries.

Plastic pollution is a growing problem; everyday it chokes our waterways, damages marine ecosystems, and becomes part of the marine food chain. All the plastics that end up in our waterways eventually break up into smaller and smaller pieces. Some of it floats, some of it sinks, but none of it ever disappears. Plastic continues to accumulate and circulate in our environment where marine animals can mistake it for food that can cause starvation, dehydration, internal damage or even death. When this growing plastic pollution finds its way into our marine food chain, it can eventually affect human health when we eat seafood.

Junk Food: plastic pollution is a growing threat to seabirds

A new study on seabirds and plastic rubbish gives a new meaning to the term ‘junk food’. New Zealand is well known for being the world’s seabird capital, with 10% of all seabirds on the planet breeding here. What’s less well known is the enormous – and rapidly growing - threat that plastic rubbish in the ocean poses to them.Seabirds eat the plastic, after mistaking it to for food, and it can block or rupture their gut, or lead to poisoning caused either by toxins in the plastic itself or by chemicals that the plastic has absorbed.
The research, published in theProceedings of the National Academy of Sciences, also says that the problem is worst, not in tropical gyres such as the Pacific’s great garbage patch which are known to accumulate vast amounts of plastic rubbish, but rather in the southern ocean, where plastic pollution is less but seabird numbers are at their highest.
Lead researcher Dr Chris Wilcox from CSIRO in Australia says the study’s key findings are summarised in the paper’s title: ‘Threat of plastic pollution to seabirds is global, pervasive and increasing.’
“When we analyse all the data we find, essentially, that plastic is in the majority of the world’s seabirds, whether you think of that that by individual birds or by species,” says Dr Wilcox. “And that appears to be growing.”
Worldwide plastic production has been doubling every 11 years, and in places the amount of plastic pollution has reached more than half a million pieces per square kilometre of ocean. Plastic debris concentrates in five large tropical ocean gyres, such as the well-known Pacific garbage patch. But surprisingly the study has found that the highest risk to seabirds from plastics actually occurs in the southern ocean.
Co-author Dr Denise Hardesty from CSIRO Oceans and Atmosphere says seabirds are excellent indicators of ecosystem health. “Finding such widespread estimates of plastic in seabirds is borne out by some of the fieldwork we’ve carried out where I’ve found nearly 200 pieces of plastic in a single seabird,” she says.