Ditch plastic dog poo bags, go compostable



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Don’t do these doggie-doo don’ts.
Shutterstock

M. Leigh Ackland, Deakin University

We humans have a habit of avoiding our waste. We find organic waste particularly unpleasant. We bag it and dispose of it as soon as possible.

Even the most environmentally conscious person would rather not handle something like decomposing food or dog poo with their bare hands. Plastic bags are often the first step we take to disconnect ourselves from our waste – until we can get rid of it somewhere else.

Traditional plastic bags are made from ethylene, derived from petroleum or natural gas. Ethylene does not degrade easily. So these types of bags are major contributors to plastic pollution.

More than three-quarters of plastic ends up in landfill, while up to 5% finds its way to the ocean. Only 9% of plastics are recycled.




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Many environmentally conscious pet owners are turning to biodegradable bags as the solution to their doggy-doo woes, but many brands won’t break down in landfill, compounding the problem. Alternatives are at hand, though, with compostable bags and community sharing programs that can help non-composters.

A ‘biodegradable’ statement on a bag isn’t enough: it needs a logo

“Biodegradable” means something that can potentially be broken down naturally in the environment, particularly by microorganisms but also by other factors such as heat, light and oxygen. We usually think of biodegradable materials as derived from natural sources such as plants, but synthetic materials can also be biodegradable.

But there are issues with the term “biodegradable bag”. Bags can be labelled biodegradable, but after being used and discarded they might only partly decompose because the conditions are not right for full decomposition. Or else the decomposition might take a long time.

Full decomposition means complete conversion of the bag into simple substances such as carbon dioxide and water that can be re-used by microorganisms like bacteria and fungi.

Food becomes poop, which becomes…?
Carol Von Canon/Flickr, CC BY-NC-SA

The biodegradability of plastic can be measured in a laboratory using methods such as carbon tracking. There are international standards for testing biodegradability of plastics. The International Organization for Standardization (ISO) has developed these standards.

Unfortunately, ocean and landfill environments are not conducive for degradation of biodegradable plastic. Marine environments often don’t contain the right types of microorganisms needed to break down plastics, or there aren’t enough to be effective in a reasonable time frame. Landfill conditions often lack oxygen, which limits the types of microorganisms that can exist there.

Compost, however, provides an ideal environment for biodegradation. Compost contains a diverse range of organic materials that support the growth of many different varieties of organisms.

DNA sequencing has revealed the huge diversity of microorganisms that exist in compost. These include bacteria, fungi and invertebrates that can digest a wide range of organic materials. In particular, fungi are found to possess enzymes that are capable of breaking down many different organic substances.

Compost to the rescue

You can now buy compostable bags. These are a type of biodegradable bag that is suitable for disposal in compost only (not in the ocean or landfill!).

How can you tell if a compostable bag can actually be fully broken down in compost? Standards Australia produces standards for the biodegradability of plastic bags. Code AS 4736-2006 specifies a biodegradable plastic that is suitable for overall composting (which includes industrial processes) and other microbial treatment, while AS 5810-2010 specifies home composting.

Standards Australia provide a brief overview of the testing carried out for AS 5810-2010. Other countries have similar standards – for example, the US has ASTM code D6400, which certifies that the material meets the degradation standard under controlled composting conditions.

The Australian Bioplastics Association administers a voluntary verification scheme. This enables manufacturers or importers to have their plastic materials tested and certified.

There is a double arrow logo you can watch out for on bags that have been certified as home compostable and there is a seedling logo for certified compostable. If you cannot locate a certified compostable bag in your area, you can source them online. Make sure they have have the certified compostable logo of the country from which they come.

It is interesting to observe the biodegradability of a plastic bag in your compost heap, as I did with a compostable bag full of dog poo. After two weeks buried in the compost, the only evidence of the bag was some small black fragments. These looked like leaf mould except they had the print from the bag label on them. In comparison, a normal plastic bag buried at the same time was completely unaltered. Of course, this experiment is not proof of total bag degradation – proper laboratory testing would be required for this.




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What if you can’t compost?

If you cannot compost, you will probably be relying on your local council to dispose of your waste. If the council uses landfill for waste disposal then there may be no point in using compostable bags for your waste, as landfill does not have the right conditions for composting to occur.

If you have a kerbside green waste collection that is composted, this service most likely will not accept food waste at the moment – which means dog poo is very unlikely to be included. Nor may compostable bags be allowed in green waste collections. Some councils, however, are working towards food organics/green organics waste collections for the future, and these may include compostable bags.

Moyne Shire in western Victoria, for instance, provides compostable bags for dog poo and accepts it along with green waste in its fortnightly “FOGO” collection.

If you have material for composting but do not have a compost heap, you can join Sharewaste. Sharewaste links people who want to recycle their organic waste with their neighbours who can use the waste for composting, worm farms or chickens. So this is a way to avoid sending your organic waste to landfill.

Composting your organic waste is like harvesting rain into your water tank or tapping into sunlight for your energy needs. These things are meaningful beyond their utility; they connect you to nature and give insights into the natural cycles of life on planet Earth.The Conversation

M. Leigh Ackland, Professor in Molecular Biosciences, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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There’s no ‘garbage patch’ in the Southern Indian Ocean, so where does all the rubbish go?


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Plastic waste on a remote beach in Sri Lanka.
Author provided

Mirjam van der Mheen, University of Western Australia; Charitha Pattiaratchi, University of Western Australia, and Erik van Sebille, Utrecht University

Great areas of our rubbish are known to form in parts of the Pacific and Atlantic oceans. But no such “garbage patch” has been found in the Southern Indian Ocean.

Our research – published recently in Journal of Geophysical Research: Oceans – looked at why that’s the case, and what happens to the rubbish that gets dumped in this particular area.

Every year, up to 15 million tonnes of plastic waste is estimated to make its way into the ocean through coastlines (about 12.5 million tonnes) and rivers (about 2.5 million tonnes). This amount is expected to double by 2025.




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Some of this waste sinks in the ocean, some is washed up on beaches, and some floats on the ocean surface, transported by currents.

The garbage patches

As plastic materials are extremely durable, floating plastic waste can travel great distances in the ocean. Some floating plastics collect in the centre of subtropical circulating currents known as gyres, between 20 to 40 degrees north and south, to create these garbage patches.

The Great Pacific Garbage Patch.
National Oceanic and Atmospheric Administration

Here, the ocean currents converge at the centre of the gyre and sink. But the floating plastic material remains at the surface, allowing it to concentrate in these regions.

The best known of these garbage patches is the Great Pacific Garbage Patch, which contains about 80,000 tonnes of plastic waste. As the National Oceanic and Atmospheric Administration points out, the “patches” are not actually clumped collections of easy-to-see debris, but concentrations of litter (mostly small pieces of floating plastic).

Similar, but smaller, patches exist in the North and South Atlantic Oceans and the South Pacific Ocean. In total, it is estimated that only 1% of all plastic waste that enters the ocean is trapped in the garbage patches. It is still a mystery what happens to the remaining 99% of plastic waste that has entered the ocean.

Rubbish in the Indian Ocean

Even less is known about what happens to plastic in the Indian Ocean, although it receives the largest input of plastic material globally.

For example, it has been estimated that up to 90% of the global riverine input of plastic waste originates from Asia. The input of plastics to the Southern Indian Ocean is mainly through Indonesia. The Australian contribution is small.

The major sources of riverine input of plastic material into the Indian Ocean.
The Ocean Cleanup, CC BY-NC-ND

The Indian Ocean has many unique characteristics compared with the other ocean basins. The most striking factor is the presence of the Asian continental landmass, which results in the absence of a northern ocean basin and generates monsoon winds.

As a result of the former, there is no gyre in the Northern Indian Ocean, and so there is no garbage patch. The latter results in reversing ocean surface currents.

The Indian and Pacific Oceans are connected through the Indonesian Archipelago, which allows for warmer, less salty water to be transported from the Pacific to the Indian via a phenomenon called the Indonesian Throughflow (see graphic, below).

Schematic currents and location of a leaky garbage patch in the southern Indian Ocean: Indonesian Throughflow (ITF), Leeuwin Current (LC), South Indian Counter Current (SICC), Agulhas Current (AC).
Author provided

This connection also results in the formation of the Leeuwin Current, a poleward (towards the South Pole) current that flows alongside Australia’s west coast.

As a result, the Southern Indian Ocean has poleward currents on both eastern and western margins of the ocean basin.

Also, the South Indian Counter Current flows eastwards across the entire width of the Southern Indian Ocean, through the centre of the subtropical gyre, from the southern tip of Madagascar to Australia.

The African continent ends at around 35 degrees south, which provides a connection between the southern Indian and Atlantic Oceans.

How to follow that rubbish

In contrast to other ocean basins, the Indian Ocean is under-sampled, with only a few measurements of plastic material available. As technology to remotely track plastics does not yet exist, we need to use indirect ways to determine the fate of plastic in the Indian Ocean.

We used information from more than 22,000 satellite-tracked surface drifting buoys that have been released all over the world’s oceans since 1979. This allowed us to simulate pathways of plastic waste globally, with an emphasis on the Indian Ocean.

Global simulated concentration of floating waste after 50 years.
Mirjam van der Mheen, Author provided

We found that unique characteristics of the Southern Indian Ocean transport floating plastics towards the ocean’s western side, where it leaks past South Africa into the South Atlantic Ocean.

Because of the Asian monsoon system, the southeast trade winds in the Southern Indian Ocean are stronger than the trade winds in the Pacific and Atlantic Oceans. These strong winds push floating plastic material further to the west in the Southern Indian Ocean than they do in the other oceans.

So the rubbish goes where?

This allows the floating plastic to leak more readily from the Southern Indian Ocean into the South Atlantic Ocean. All these factors contribute to an ill-defined garbage patch in the Southern Indian Ocean.

Simulated concentration of floating waste over 50 years in the Indian Ocean.

In the Northern Indian Ocean our simulations showed there may be an accumulation of waste in the Bay of Bengal.




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It is also likely that floating plastics will ultimately end up on beaches all around the Indian Ocean, transported by the reversing monsoon winds and currents. Which beaches will be most heavily affected is still unclear, and will probably depend on the monsoon season.

Our study shows that the atmospheric and oceanic attributes of the Indian Ocean are different to other ocean basins and that there may not be a concentrated garbage patch. Therefore the mystery of all the missing plastic is even greater in the Indian Ocean.The Conversation

Mirjam van der Mheen, PhD Candidate in Oceanography, University of Western Australia; Charitha Pattiaratchi, Professor of Coastal Oceanography, University of Western Australia, and Erik van Sebille, Associate Professor in Oceanography and Climate Change, Utrecht University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We need a legally binding treaty to make plastic pollution history



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The world urgently needs to move past plastic.
Veronika Meduna

Trisia Farrelly, Massey University

A powerful marriage between the fossil fuel and plastic industries threatens to exacerbate the global plastic pollution crisis. The Center for International Environmental Law (CIEL) estimates the next five years will see a 33-36% surge in global plastics production.

This will undermine all current efforts to manage plastic waste. It is time to stop trying (and failing) to bail out the bathtub. Instead, we need to turn off the tap.




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The United Nations Environment Assembly (UNEA) has recognised plastic pollution as a “rapidly increasing serious issue of global concern that needs an urgent global response”. An expert group formed last year proposed an international treaty on plastic pollution as the most effective response.

Together with Giulia Carlini, at CIEL, I was part of a 30-strong group of non-governmental organisations within this expert group attending the UNEA summit this week to discuss how we can start making plastic pollution history.

Unfortunately, despite strong statements from developing countries, including the Pacific Island states, a small group of countries stalled negotiations. This effectively turns back the clock on ambitious global action, and leaves us more desperate than ever for a real solution to our plastic problem.

Why we need a treaty

The first step is to reject the many false solutions that pop up in our news feeds.

Recycling is one of those false solutions. The scale of plastic production is too big for recycling alone. Of all the plastics produced between 1950 and 2015, only 9% have been recycled. This figure is set to plummet as China and a growing number of developing countries are rejecting plastic waste from Australia, New Zealand and the rest of the world.

China had been a major destination for Australia and New Zealand’s recyclable waste. China’s shutdown meant Australia lost the market for a third of its plastic waste. It also left New Zealand with 400 tonnes of stockpiled plastic waste last year.

With limited domestic recycling facilities, Australia and New Zealand are seeking new markets. Last year, New Zealand sent about 250,000 tonnes of plastic to landfill, and a further 6,300 tonnes to Malaysia for recycling. But now Malaysia is also rejecting other countries’ hazardous plastic waste.

Sending our platic to Asia is not a solution.
EPA/Diego Azubel, CC BY-SA

Even if we manage to find new plastic recycling markets, there is another problem. Recycling is not as safe as you might think. Flame retardants and other toxins are added to many plastics, and these compounds find a second life when plastics are recycled into new products, including children’s toys.

Plastic-to-energy is a false solution

What about burning plastic waste to generate energy? Think again. Incineration is expensive, can take decades for investors to break even. It is the opposite of a “zero waste” approach and locks countries into a perpetual cycle of producing and importing waste to “feed the beast”. And incineration leaves a legacy of contaminated air, soil, and water.

Producing lower-grade materials from plastic waste (such as roads, fenceposts and park benches) is not the solution either. No matter where we put it, plastic doesn’t go away. It just breaks into ever smaller pieces with a greater potential for harm in air, water, soil and marine and freshwater ecosystems.

This is why researchers are paying more attention to the less visible hazards posed when micro (less than 5mm long) and nano (less than 100 nanometres long) sized plastics carry pathogens, invasive species and persistent organic pollutants. They have found that plastics can emit methane contributing to greenhouse gas emissions.

Tyres wear down into microplastics which find their way into the ocean. When plastics break down to nanoparticles, they are small enough to pass through cell walls. Our clothes release plastic microfibres into water from washing machines.

Plastic is truly global

Plastic pollution moves readily around the globe. It travels through trade, on winds, river and tidal flows, and in the guts of migrating birds and mammals. We don’t always know which toxic chemicals are in them, nor their recycled content. Plastic pollution can end up thousands of kilometres from the source.

This makes plastic pollution a matter of international concern. It cannot be solved solely within national borders or regions. A global, legally binding treaty with clear targets and standards is the real game-changer we urgently need.

The NGO component of UNEA’s expert group recognised an international treaty as the most effective response. The proposed treaty has the potential to capture the full life cycle of plastics by focusing on prevention, right at the top of the waste hierarchy.

The Zero Waste hierarchy.
Zero Waste Europe

These solutions could include restricting the volume of new or “virgin” plastics in products, banning avoidable plastics (such as single-use plastic bags and straws), and curbing the use of toxic additives.




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More than 90 civil society organisations around the world and a growing number of countries have indicated early support for a treaty. Australia and New Zealand have not.The Conversation

Trisia Farrelly, Senior Lecturer, Massey University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Plastic and Marine Life


The link below is to an article reporting on how plastic is leading to reproductive problems for marine wildlife.

For more visit:
https://www.theguardian.com/environment/2019/feb/27/plastics-leading-to-reproductive-problems-for-wildlife

Why stop at plastic bags and straws? The case for a global treaty banning most single-use plastics



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Joyce Njeri, 8, walks amidst garbage and plastic bags in the Dandora slum of Nairobi, Kenya.
AP Photo/Ben Curtis, File

Anastasia Telesetsky, University of Idaho

Single-use plastics are a blessing and a curse. They have fueled a revolution in commercial and consumer convenience and improved hygiene standards, but also have saturated the world’s coastlines and clogged landfills. By one estimate 79 percent of all plastic ever produced is now in a dump, a landfill or the environment, and only 9 percent has been recycled.

This growing legacy poses real risks. Plastic packaging is clogging city sewer systems, leading to flooding. Abandoned plastic goods create breeding grounds for mosquitoes, and can leach toxic additives such as styrene and benzene as they decompose. Single-use plastics are killing birds and harming marine life.

I study international environmental law with a focus on marine ecosystems. In my view, land-based pollution from single-use plastics is a slow-onset disaster that demands a global response.

One attractive strategy is pursuing a legally binding phase-out of most single-use plastics at the global level. I believe this approach makes sense because it would build on current national and municipal efforts to eliminate single-use packaging, and would create opportunities for new small and medium-sized businesses to develop more benign substitutes.

Plastic bag litter along the Jukskei River, Johannesburg, South Africa.
NJR ZA/Wikimedia, CC BY-SA

Single-use plastic bans

About 112 countries, states and cities around the world have already imposed bans on various single-use plastic goods. Of these measures, 57 are national and 25 are in Africa. And the list of these restrictions continues to grow.

Most of these bans target thin single-use plastic carrier bags or imports of non-biodegradable bags. Some, such as the one in Antigua-Barbuda, include other single-use or problematic items, such as foam coolers and plastic utensils. A few measures – notably, Kenya’s plastic bag law – impose stiff punishments on violators, including jail time and fines of up to US$38,000.

Groups of states are starting to enact regional policies. The East African Legislative Assembly has passed a bill to ban the manufacture, sale, import and use of certain plastic bags across its six member states, with a combined population of approximately 186 million people. And in October 2018 the European Union Parliament approved a ban on a number of single-use plastic items by 2021, along with a requirement to reduce plastic in food packaging by 25 percent by 2025 and cut plastic content in cigarette filters 80 percent by 2030.

Most of these bans are quite new or still being implemented, so there is limited research on how well they work. However, researchers at the United Nations who have reviewed 60 “national bans and levies” estimate that 30 percent of these measures have reduced consumption of plastics.

Plastics manufacturers contend that better recycling is the most effective way to reduce the environmental impact of their products. But many factors make it hard to recycle plastic, from its physical characteristics to insufficient market demand for many types of recycled plastics. In many instances, single-use plastics can only be recycled, optimistically, 10 times before their fibers become too short to be reprocessed.

Estimated number of new regulations on single-use plastics entering into force at the national level worldwide.
UNEP, CC BY

Lessons from other global bans

Several global bans and product phase-outs offer lessons for a treaty banning single-use plastic goods. The most successful case is the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer. This treaty phased out production and use of chlorofluorocarbons in a variety of products, including refrigerators and spray cans, after they were shown to harm Earth’s protective ozone layer.

Today scientists predict that stratospheric ozone concentrations will rebound to 1980 levels by the middle of this century. According to the Environmental Protection Agency, the Montreal Protocol has prevented millions of cases of skin cancer and cataracts from exposure to ultraviolet radiation. In 2016 nations adopted the Kigali Amendment, which will phase out production and use of hydrofluorocarbons, another class of ozone-depleting chemicals.

Why has the Montreal Protocol worked so well? One key factor is that every nation in the world has joined it. They did so because alternative materials were available to substitute for chlorofluorocarbons. The treaty also provided financial support to countries that needed help transitioning away from the banned substances.

Sir David Attenborough narrates the extraordinary history of the Montreal Protocol.

Where countries trying to reduce use of these chemicals fell short of their goals, the Protocol provided institutional support rather than punishing them. But it also included the option to impose trade sanctions on nations that refused to cooperate.

Another pact, the 2001 Stockholm Convention on Persistent Organic Pollutants, banned or severely limited production and use of certain chemicals that threatened human and environmental health, including specific insecticides and industrial chemicals. Today 182 nations have signed the treaty. Concentrations of several dangerous POPs in the Arctic, where global air and water currents tend to concentrate them, have declined.

Nations have added new chemicals to the list and created “elimination networks” to help members phase out use of dangerous materials such as PCBs. And producers of goods such as semiconductors and carpets that use listed chemicals are working to develop new, safer processes.

Even though the United States has not signed the Stockholm Convention, U.S. companies have largely eliminated production of the chemicals that the treaty regulates. This shows that setting a global standard may encourage nations to conform in order to maintain access to global markets.

Other international bans have been less successful. In 1989, seeking to reduce the slaughter of elephants for their tusks, parties to the Convention in Trade of Endangered Species banned ivory sales by ending trade in African elephant parts. Initially demand for ivory fell, but in 1999 and 2008 treaty states allowed African nations to sell ivory stockpiles to Japan and China, ostensibly to fund conservation. These two sales reignited global demand for ivory and created unregulated domestic markets that stimulated high levels of poaching.

Malaysian customs officials display smuggled tusks seized at Kuala Lumpur International Airport in 2017. Demand for ivory continues to fuel poaching and illegal trade despite an international ban on sales of elephant parts.
AP Photo/Vincent Thian

An opportunity to lead

What lessons do these treaties offer for curbing plastic pollution? The Montreal Protocol shows that bans can work where substitute products are available, but require reliable monitoring and the threat of sanctions to deter cheating. The Stockholm Convention suggests that industries will innovate to meet global production challenges. And struggles to curb the ivory trade offer a cautionary message about allowing exceptions to global bans.

I believe the rapid spread of single-use plastic bans shows that enough political support exists to launch negotiations toward a global treaty. Emerging economies such as Kenya that are aggressively tackling the problem are especially well placed to take a lead at the U.N. General Assembly in calling for talks on stemming the tide of plastic pollution.The Conversation

Anastasia Telesetsky, Professor of International Environmental Law , University of Idaho

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Coles Plastic Environmental Vandalism


The link below is to an article reporting on the latest episode of plastic trash being handed out by Coles.

For more visit:
https://www.theguardian.com/business/2019/feb/13/a-legacy-of-plastic-waste-coles-launches-new-collectables-series