Microplastics: The Invisible Plastic


The Invisible Plastic - Size Matters 


While research has rapidly established that all plastics create problems within the marine environment, the extent of microplastic (pieces of plastic less than 5mm in diameter) now evident in our oceans presents a threat of the highest order to our biodiversity.

“Plastic is so permanent and so indestructible that when you’ve tossed it, in the ocean, or in a dustbin… it does not go away” David Attenborough.


While there is a significant level of uncertainty regarding the amount of microplastic pollution found in the environment, Boomerang Alliance estimates that between 99-130,000 tonnes / p.a. of plastic enters the ocean from Australian sources of which some 32,000 tonnes / p.a. are believed to be primary microplastics. These materials include the synthetic rubber dust our tyres leave on the road during use (potentially 23-24,000 tonnes p.a.); the loss of plastic productions pellets (nurdles) during plastic manufacture (potentially as much as 15,000 tonnes p.a.), synthetic textile fibres lost during laundry (5-7,000 tonnes p.a.); and the discharge of microbeads used in personal care and home cleaning (650 tonnes p.a.). 

The level of microplastic proliferation in our marine environment is also supported by research undertaken in 2014 by researchers from the Sydney Institute of Marine Science who found “alarming” levels of microplastic pollution in Sydney Harbour. microplastic_fragments_.pngSediment samples taken at 27 sites across the Harbour found concentrations of microplastics ranged from 0-10 to a high of 61-100 particles per 100ml of sediment in Middle Harbour. (see below)

It is important to address microplastics specifically when developing any Threat Abatement Plan to manage dangerous marine debris. Size matters when dealing with marine plastic pollution – most obviously the smaller the piece of plastic, the more difficult it becomes to capture at the end of its use - with filtration systems needing to screen items with a diameter less than a human hair.  Similarly, while common macro litter items like drink bottles, plastic bags and polystyrene ‘peanuts’ may survive within the marine environment ‘forever’, they begin to fragment into microplastics within weeks of entering our waterways.



The graphic below outlines how microplastics reach our oceans:


All plastics have similar properties to natural fats, acting as a ‘sponge’ to remove and concentrate contaminants from the water column, but size also matters when considering the potential toxicity associated with marine plastics. Put simply the smaller the piece of plastic the larger the relative surface area to weight ratio. This means there is an increased area of material coming in contact with water – which increases the amount of other pollutants that microplastics will sorb from surrounding sea water. Testing the potential toxicity in fish ingesting microbeads, scientists found that a single microbead can be up to a million times more toxic than the water around it![1]

Finally, and perhaps most importantly, the smaller the piece of plastic the greater the proportion of biodiversity likely to ingest these toxic pollutants – whether directly or by predator species (including us) eating plastic contaminated marine species.

To date, the Australian Government has been slow to respond and while recent announcements regarding Container Deposit Schemes in NSW, Qld, ACT and now WA, targeting the largest source of plastic overall are welcome; the Federal Government needs to move quickly on microbeads.  It has threatened to take regulatory action targeting microbeads and is currently negotiating a voluntary agreement with industry which may apply to both cosmetics and cleaning products.  However there remains no overarching plan to deal with microplastic pollution.

In part, this inertia stems from the great deal of uncertainty regarding the total extent of micro and nano scale plastics in our oceans – yet globally scientists and governments are confident the evidence of the problem is sufficient to act. Just last month in July UNEP released the advance copy of its study “Marine plastic debris and microplastics – Global lessons and research to inspire action and guide policy change’ finding there is sufficient evidence that marine plastics and microplastics are having an unacceptable impact to invoke the Precautionary Approach. This means that society should not wait until there is unequivocal and fully quantified evidence of the degree of impact before acting to reduce plastic inputs to the ocean.

In order to develop an effective Threat Abatement Plan to combat harmful marine plastic pollution there needs to be specific management plans associated with microplastic. These include:

- Regulatory Enforcement – A significant source of microplastics are fugitive emissions from industrial processes. These include the loss of pellets from plastic manufacturing plants; failure of waste facilities to ensure they contain lightweight plastics (e.g. single use bags) within their premises; and the escape of residual plastics and synthetic fibres from recycling facilities. Most recently, Dr Mark Browne of UNSW identified high levels of microplastics in the compost produced at waste treatment facilities as having an unacceptably high level of plastic residuals within the material used as soil conditioners. In each of these instances the plastic releases are unlawful – yet state and territory agencies are failing to ensure our environmental regulations are enforced.

Recommendation: State and Territory Environment Protection agencies must start enforcing regulations. A key component of the Threat Abatement Plan should be to require environmental regulators to publicly report on their inspection, licensing and enforcement activities to ensure fugitive plastics are retained.

- Synthetic Fibres – banning synthetic clothing and textiles from sale is probably a step too far and an impractical solution, but requiring all washing machines to be fitted with filters is a relatively simple and inexpensive solution to capturing the vast majority of fibres being released into our waterways.

Recommendation: Require all washing machines sold in Australia from 1/1/2018 to be fitted with a filtration device capable of capturing at least 80% of the fibrous material discharged during a wash cycle.  

- Microbeads – in February 2016 Environment Minister, Greg Hunt announced that if voluntary action did not eliminate microbeads from personal care products, the Commonwealth would introduce regulations (in 2018) to ban their production and importation. This is a good start but the responses is seen as being too slow - just last week RMIT released new research showing the threat of microbeads within our food chain. Lead researcher Dr Brad Clarke said “We shouldn't have to wait one or two years for these products to be banned, because in that time, billions more microbeads will be released into the environment."[2]

It’s essential the proposed Commonwealth phase out of microbeads is focussed on personal care products and other products containing microbeads like detergents, car and floor polishes which dwarf the number of microbeads in cosmetics. In August last year a report for the German Government identified that annually approximately 500 tonnes of primary microplastics composed of polyethylene are used in cosmetic products, with another 100 tonnes p.a. used in detergents, disinfectants and blasting agents and that micro particles in synthetic waxes (e.g. floor and car polishes) were estimated at around 100,000 tonnes per year.[3]

Recommendations): Personal care, home cleaning and synthetic waxes or polishes containing micro plastic particles should be banned from importation or manufacture in Australia from July 2017. The same product range should be banned from sale from 1/1/2018 in Australia.

- While the abrasion of tyres during driving is a major point source of plastic pollution it is also important to recognise that this is a necessary evil to ensure road safety. The alternatives (moving back to natural latex) also have wide reaching ramifications for the preservation of old growth forests etc. – meaning that there is no better alternative currently available. To this end we do not recommend any action to eliminate this source.

[1] Chelsea M. Rochman, Eunha Hoh, Tomofumi Kurobe & Swee J. Teh, Ingested plastic transfers hazardous chemicals to fish and induces hepatic stress, .

[2] http://www.sciencealert.com/microbeads-are-causing-the-fish-we-eat-to-become-toxic-study-finds

[3] See: Sources of microplastics relevant to marine protection in Germany 


Anthony L. Andrady: Microplastics in the Marine Environment Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA

Germany, (2015): Sources of Microplastic relevant to marine protection in Germany 

GESAMP: Sources, Fate and Effects of Microplastic in the Marine Environment: A Global Assessment 

Norwegian Environment Agency, (2014): Sources of Microplastic Pollution in the Marine Environment 




In order to develop a 'community owned' threat abatement plan to cut 70% of plastic pollution entering our waterways by 2020 we need your feedback and input! Please complete this quick poll to have your say on what issues within marine plastic pollution should be prioritised and help us turn back the toxic tide. 


For further engagement on this week's blog content, please use the comment section below - we would love to hear your thoughts. 


Showing 6 reactions

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  • Christina Attwell
    commented 2016-09-10 19:20:51 +1000
    Ban all plastics that cannot be re-cycled into another product.
  • William Zappa
    commented 2016-09-09 10:05:25 +1000
    There’s one area of plastics not mentioned, perhaps because they are not ‘micro’ enough, but polystyrene (bean bags, insulation, protective packaging for a myriad of products, garden/potting mix) is a huge problem. It is not unusual to see a broken piece of ‘packaging’ lying in the road and being crushed and broken down to the individual ‘beads’ by passing traffic which quite easily get washed into our water ways. I recently bought a large carpentry tool that came packed within a very large polystyrene protective case within a cardboard box. There are some companies that use recycled cardboard as the protective casing and this is easily recycled again. Perhaps all companies should be encouraged to use cardboard instead of the almost impossible to recycle polystyrene!
  • Sandy Killick
    commented 2016-09-08 22:26:42 +1000
    Hi thanks for the chance to complete the online survey. This is a really critical issue – thanks for raising it’s profile.

    It would be great if the Boomerang Alliance could help all levels of Govt think through a series of stages that would target the highest risk plastics first and then work through the remaining ones to reach the highest standard in our marine environments possible. Obviously this will take a few years to implement/achieve but it will be a much better position than the one we are in now.

    I frequent the Sydney Fish Markets on a weekly/fortnightly basis and am constantly amazed by the amount of plastic waste that the take away seafood restaurants/cafes/fruit vege shops generate that end up in the nearby water. It will kill the very environment that supports their businesses.

    Given the recent profiling on microbeads and the food chain I actually wonder if I should be consuming fish. Are there any studies the BA can commission or report on regarding uptake of plastic residues in the popular types of fish sold at places like the Sydney Fishmarket and other waterside locations please? That might help to create a sense of urgency about this issue.
  • Kathy Kemeny
    commented 2016-09-08 17:30:46 +1000
    I have just completed the online survey. All options should be a priority for government intervention, not just three. I know single use plastic bags, ghost nets and microplastics are causing devestation in our marine ecosystems. Hopefully, continuing consumer education programs will have a beneficial impact on plastic beverage containers, balloons, cigarette butts and plastic-coated single use coffee cups. Perhaps ongoing
    consumer education is also a vital factor in the government intervention strategy.
  • Aida Tebbutt
    commented 2016-09-06 19:31:50 +1000
    I have just completed the online survey. It was very difficult to choose 3 products that should be a priority for government intervention. All of the options mentioned appear to be of a concern and need to be addressed and prevented. However, I do not have an informed position to know which of the products mentioned in the survey are causing the most damage. The majority of the visible plastic on my local beach, which is Shelly Beach on the NSW Central Coast, and along the roadsides and nature reserves in my area, are plastics from a huge variety of takeaway food and snack food packaging, a huge variety of plastic bags and cigarette butts. It would appear that most of this is from littering. Apparently we already have the Australian Packaging Covenant (APC) which is supposed to ‘provide a sustainable packaging initiative which aims to change the culture of business to design more sustainable packaging, increase recycling rates and reduce packaging litter’ etc. Clearly then this is woefully inadequate. How is the effectiveness of the covenant being assessed? The government needs to do much more here. What is not being realistically addressed is the end cycle of many products. (Even though this is a requirement of the packaging covenant). The sheer amount of packaging that is non bio-degradable for single use products is incomprehensible. Biodegradable materials would have to be a minimum requirement for all of these products as much of it is littered and therefore not recycled. This is so evident but manufacturers are not taking the required responsibility. This needs to be addressed. Why do companies need to be shamed by environmental lobby groups to change their practices? How is it acceptable for industry to adopt this irresponsible packaging model? Minimising the environmental impact of packaging needs to be front and foremost when manufacturers choose their packaging, before sale to the consumer. Trying to clean up after the harmful material has been released into the environment, whilst necessary, is totally inadequate and indeed impossible. I think it is offensive that our rates/taxes etc. are used to clean up after industries that have profited from environmentally unacceptable plastic and plastic packaging choices.
  • Carolyn Sharp
    commented 2016-09-06 14:10:55 +1000
    While I think that 2 years is too long to wait to ban the micro plastics from products I realise that it can’t be done overnight either. I would like to see a shorter time span, maybe with incentives for early completion.
    I agree that the textile industry should be held accountable for the micro fibres that are released from their products but in the meantime the fact remains that these are being released all the time. Until they can prove that their products are no longer releasing fibres I think they should compulsorily contribute to the cost to develop (and maintain) the filtration at the water treatment system.