Nedeljka Rosic, Southern Cross University; Joanne Bradbury, Southern Cross University, and Sandra Grace, Southern Cross UniversityThere’s a weedkiller used in Australia that’s so toxic, one sip could kill you. It’s called paraquat and debate is brewing over whether it should be banned.
Paraquat is already outlawed in many places around the world. The Australian Pesticides and Veterinary Medicines Authority has been reviewing paraquat’s use here for more than two decades, and its final decision is due later this year.
We are medical and environmental scientists, and have researched the harmful effects of paraquat, even when it’s used within the recommended safety range. We strongly believe the highly toxic chemical should be banned in Australia.
The potentially lethal effects on humans are well known. In Australia in 2012, for example, a farmer died after a herbicide containing paraquat accidentally sprayed into his mouth. And our research has found paraquat also causes serious environmental damage.
Paraquat: the story so far
Paraquat is registered as a schedule 7 poison on the national registration scheme, meaning its use is strictly regulated.
Suppliers of paraquat say it should not be banned, insisting herbicides containing it are safe for people and the environment when used for their intended purpose and according to label instructions.
Paraquat has been banned in more than 50 countries, including the United Kingdom, China, Thailand and European Union nations. However, it’s still widely used by farmers in the developing world, and in Australia and the United States.
A chemical peril
Paraquat is a non-selective herbicide, which means it kills plants indiscriminately. It does so by inhibiting photosynthesis, the process by which plants convert sunlight into chemical energy.
Paraquat stays in the environment for a long time. It’s well known for causing collateral damage to plants and animals. For example, even at very low concentrations, paraquat has been found to harm the growth of honey bee eggs.
Paraquat can have unintended consequences for biological organisms and the environment, particular in waterways. Our recent paper summarised the evidence of the harmful effects of paraquat at realistic field concentrations.
We found evidence that paraquat can severely inhibit healthy bacterial growth in aquatic environments, which in turn affects nutrient cycling and the decomposition of organic matter.
The research also shows paraquat can distort tropical freshwater plankton communities by negatively impacting metabolic diversity and reducing phytoplankton growth.
In fish, paraquat has been found to lead to a death rate of common carp three times higher than the weed it is used to control.
‘One sip can kill’
In addition to the environmental effects, of course, paraquat is highly toxic to humans. A small accidental sip can be fatal and there is no antidote.
The US Centers for Disease Control and Prevention says paraquat is a leading cause of fatal poisoning in parts of Asia, the Pacific Islands, and South and Central Americas.
Paraquat enters the body through the skin, digestive system or lungs. If ingested in sufficient amounts, it causes lung damage, leading to pulmonary fibrosis and death through respiratory failure. The liver and kidney can also fail.
Several recent incidents in Australia demonstrate the risks of paraquat poisoning due to human error, even within the current strict regulations.
According to news reports, the Queensland farmer poisoned by paraquat in 2012 was filling a pressure pump to control weeds on his property. The unit cracked and paraquat sprayed over his body and face, entering his mouth.
In 2017, an adult with autism took a sip from a Coke bottle used to store paraquat. The bottle had been left in a disabled toilet at a sports ground in New South Wales. The man was initially given 12 hours to live, but fortunately recovered after two weeks in hospital.
Paraquat: not worth the risk
There’s a growing awareness of the threats posed by global chemical use. In fact, a paper released this week suggests the potential risk to humanity is on a scale equivalent to climate change.
Paraquat is no doubt an effective herbicide. However, in our view, the risks it poses to humans and the environment outweigh the agricultural benefits.
Current regulation in Australia has not prevented harm from paraquat. It’s time for Australia to join the movement towards a global ban on this toxic chemical.
Editor’s note: the article has been updated to reflect the fact products other than Gramoxone also contain paraquat.
Nedeljka Rosic, Senior Lecturer, Southern Cross University; Joanne Bradbury, Senior Lecturer, Evidence Based Healthcare, Faculty of Health, Southern Cross University, and Sandra Grace, Professor, Southern Cross University
To start dealing with Australia’s mounting plastic crisis, the federal government last week launched its first National Plastics Plan.
The plan will fight plastic on various fronts, such as banning plastic on beaches, ending polystyrene packaging for takeaway containers, and phasing in microplastic filters in washing machines. But we’re particularly pleased to see a main form of biodegradable plastic will also be phased out.
Biodegradable plastic promises a plastic that breaks down into natural components when it’s no longer wanted for its original purpose. The idea of a plastic that literally disappears once in the ocean, littered on land or in landfill is tantalising — but also (at this stage) a pipe dream.
Why ‘biodegradable’ ain’t that great
“Biodegradable” suggests an item is made from plant-based materials. But this isn’t always the case.
A major problem with “biodegradable” plastic is the lack of regulations or standards around how the term should be used. This means it could, and is, being used to refer to all manner of things, many of which aren’t great for the environment.
Many plastics labelled biodegradable are actually traditional fossil-fuel plastics that are simply degradable (as all plastic is) or even “oxo-degradable” — where chemical additives make the fossil-fuel plastic fragment into microplastics. The fragments are usually so small they’re invisible to the naked eye, but still exist in our landfills, water ways and soils.
The National Plastics Plan aims to work with industry to phase out this problematic “fragmentable” plastic by July, 2022.
Some biodegradable plastics are made from plant-based materials. But it’s often unknown what type of environment they’ll break down in and how long that would take.
Those items may end up existing for decades, if not centuries, in landfill, litter or ocean as many plant-based plastics actually don’t break down any quicker than traditional plastics. This is because not all plant-based plastics are necessarily compostable, as the way some plant-based polymers form can make them incredibly durable.
So it’s best to avoid all plastic labelled as biodegradable. Even after the ban eliminates fragmentation — the worst of these — there’s still no evidence remaining types of biodegradable plastics are better for the environment.
Compostable plastics aren’t much better
Compostable plastic is another label you may have come across that’s meant to be better for the environment. It’s specifically designed to break down into natural, non-toxic components in certain conditions.
Unlike biodegradable plastics, there are certification standards for compostable plastics, so it’s important to check for one the below labels. If an item doesn’t have a certification label, there’s nothing to say it isn’t some form of mislabelled “biodegradable” plastic.
But most certified compostable plastics are only for industrial composts, which reach very high temperatures. This means they’re unlikely to break down sufficiently in home composts. Even those certified as “home compostable” are assessed under perfect lab conditions, which aren’t easily achieved in the backyard.
And while certified compostable plastics are increasing, the number of industrial composting facilities that actually accept them isn’t yet keeping up.
Nor are collection systems to get your plastics to these facilities. The vast majority of kerbside organics recycling bins don’t currently accept compostable plastics and other packaging. This means placing compostable plastics in these bins is considered contamination.
Even if you can get your certified compostable plastics to an appropriate facility, composting plastics actually reduces their economic value as they can no longer be used in packaging and products. Instead, they’re only valuable for returning nutrients to soil and, potentially, capturing a fraction of the energy used to produce them.
Finally, if you don’t have an appropriate collection system and your compostable plastic ends up in landfill, that might actually be worse than traditional plastic. Compostable plastics could release methane — a much more potent greenhouse gas than carbon dioxide — in landfill, in the same way food waste does.
So, you should only consider compostable plastics when you have a facility that will take them, and a way to get them there.
And while the National Plastics Plan and National Packaging Targets are aiming for at least 70% of plastics to be recovered by 2025 (including through composting), nothing yet has been said about how collection systems will be supported to achieve this.
Is recycling helpful?
In Australia, systems for recycling the most common types of plastic packaging are well established and in many cases operate adequately. However, there are still major issues.
For example, many plastic items can’t be recycled in our kerbside bins (including soft and flexible plastics such as bags and cling films, and small items like bottle lids, plastic cutlery and straws). Placing these items in your kerbside recycling bin can contaminate other recycling and even damage sorting machines.
What’s more, much of the plastic collected for recycling doesn’t have high value “end markets”. Only two types of plastic — PET (think water or soft drink bottles and some detergent containers) and HDPE (milk bottles, shampoo/conditioner/detergent containers) — are easily turned back into new plastic containers.
The rest end up in a stream called “mixed plastics”, much of which we have traditionally exported overseas for recycling due to low demand here. The new waste export ban may help fix this in the future.
So what do you do about plastic?
The obvious answer then, is to eliminate problematic plastic altogether, as the National Plastics Plan is attempting to do, and replace single-use plastics with reusable alternatives.
Little actions such as bringing your reusable water bottle, coffee cup and cutlery, can add up to big changes, if adequately supported by businesses and government to create a widespread culture shift. So too, could a swing away from insidious coffee capsules, cling wrap and cotton buds so many of us depend on.
Opting too, for plastic items made from recycled materials can make a big impact on the feasibility of plastic recycling.
If you do end up with plastic on your hands, take a quick glance at the graphic above, or read the University Technology Sydney’s Detailed Decision Guide to Disposing of Plastics.
Jenni Downes, Research Fellow, BehaviourWorks Australia (Monash Sustainable Development Institute), Monash University; Kim Borg, Research Fellow at BehaviourWorks Australia, Monash Sustainable Development Institute, Monash University, and Nick Florin, Research Director, Institute for Sustainable Futures, University of Technology Sydney
Last week San Francisco became the latest city to ban natural gas in new buildings. The legislation will see all new construction, other than restaurants, use electric power only from June 2021, to cut greenhouse gas emissions.
San Francisco has now joined other US cities in banning natural gas in new homes. The move is in stark contrast to the direction of energy policy in Australia, where the Morrison government seems stuck in reverse: spruiking a gas-led economic recovery from the COVID-19 pandemic.
Natural gas provides about 26% of energy consumed in Australia — but it’s clearly on the way out. It’s time for a serious rethink on the way many of us cook and heat our homes.
Cutting out gas
San Francisco is rapidly increasing renewable-powered electricity to meet its target of 100% clean energy by 2030. Currently, renewables power 70% of the city’s electricity.
The ban on gas came shortly after San Francisco’s mayor London Breed announced all commercial buildings over 50,000 square feet must run on 100% renewable electricity by 2022.
Buildings are particularly in focus because 44% of San Franciscos’ citywide emissions come from the building sector alone.
Following this, the San Francisco Board of Supervisors unanimously passed the ban on gas in buildings. They cited the potency of methane as a greenhouse gas, and recognised that natural gas is a major source of indoor air pollution, leading to improved public health outcomes.
From January 1, 2021, no new building permits will be issued unless constructing an “All-Electric Building”. This means installation of natural gas piping systems, fixtures and/or infrastructure will be banned, unless it is a commercial food service establishment.
Switching to all-electric homes
In the shift to zero-emissions economies, transitioning our power grids to renewable energy has been the subject of much focus. But buildings produce 25% of Australia’s emissions, and the sector must also do some heavy lifting.
A report by the Grattan Institute this week recommended a moratorium on new household gas connections, similar to what’s been imposed in San Francisco.
The report said natural gas will inevitably decline as an energy source for industry and homes in Australia. This is partly due to economics — as most low-cost gas on Australia’s east coast has been burnt.
There’s also an environmental imperative, because Australia must slash its fossil fuel emissions to address climate change.
While acknowledging natural gas is widely used in Australian homes, the report said “this must change in coming years”. It went on:
This will be confronting for many people, because changing the cooktops on which many of us make dinner is more personal than switching from fossil fuel to renewable electricity.
The report said space heating is by far the largest use of gas by Australian households, at about 60%. In the cold climates of Victoria and the ACT, many homes have central gas heaters. Homes in these jurisdictions use much more gas than other states.
By contrast, all-electric homes with efficient appliances produce fewer emissions than homes with gas, the report said.
Australia’s states and territories have much work to do if they hope to decarbonise our building sector, including reducing the use of gas in homes.
In 2019, Australia’s federal and state energy ministers committed to a national plan towards zero-carbon buildings for Australia. The measures included “energy smart” buildings with on-site renewable energy generation and storage and, eventually, green hydrogen to replace gas.
The plan also involved better disclosure of a building’s energy performance. To date, Australia’s states and territories have largely focused on voluntary green energy rating tools, such as the National Australian Built Environment Rating System. This measures factors such as energy efficiency, water usage and waste management in existing buildings.
The National Construction Code requires mandatory compliance with energy efficiency standards for new buildings. However, the code takes a technology neutral approach and does not require buildings to install zero-carbon energy “in the absence of an explicit energy policy commitment by governments regarding the future use of gas”.
An economically sensible move
An estimated 200,000 new homes are built in Australia each year. This represents an opportunity for states and territories to create mandatory clean energy requirements while reaching their respective net-zero emissions climate targets.
Under a gas ban, the use of zero-carbon energy sources in buildings would increase, similar to San Francisco. This has been recognised by Environment Victoria, which notes
A simple first step […] to start reducing Victoria’s dependence on gas is banning gas connections for new homes.
Creating incentives for alternatives to gas may be another approach, such as offering rebates for homes that switch to electrical appliances. The ACT is actively encouraging consumers to transition from gas.
Banning gas in buildings could be an economically sensible move. As the Grattan Report found, “households that move into a new all-electric house with efficient appliances will save money compared to an equivalent dual-fuel house”.
Meanwhile, ARENA confirmed electricity from solar and wind provide the lowest levelised cost of electricity, due to the increasing cost of east coast gas in Australia.
Future-proofing new buildings will require extensive work, let alone replacing exiting gas inputs and fixtures in existing buildings. Yet efficient electric appliances can save the average NSW homeowner around A$400 a year.
Learning to live sustainability, and becoming resilient in the face of climate change, is well worth the cost and effort.
Should we be cooking with gas?
Recently, a suite of our major gas importers — China, South Korea and Japan — all pledged to reach net-zero emissions by either 2050 or 2060. This will leave our export-focused gas industry possibly turning to the domestic market for new gas hookups.
The window to address dangerous climate change is fast closing. We must urgently seek alternatives to burning fossil fuels, and there’s no better place to start that change than in our own homes.
The link below is to a media release concerning the banning of solid fuel fires in State Forests throughout NSW due to bushfire concerns.
The link below is to an article reporting on a plan by Palau to ban commercial fishing and to create a massive marine sanctuary.
The link below is to an article that reports on Chile’s banning of bottom trawling in all vulnerable marine ecosystems.
The article below reports on great news for Australia – the giant fishing trawler has been banned for two years, which is a great win for our oceans.