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To Flush or Not to Flush – That is the Question

Ever heard of “demon snowballs”? Likely not, and it is probably putting images in your head of something cold and wet. Well, these demon snowballs are generally wet – but are not formed by snow and are not wonderfully white. These “snowballs” are wet wipes, and are called demon snowballs by wastewater treatment plant operators because of the way they get stuck in wastewater infrastructure. How is this relevant to ocean lovers? Wet wipes are a common type of marine debris – entering the environment via untreated and treated wastewater.

Although you may throw your wet wipes in the trash can – which is the best thing to do with them – many wet wipes are marketed as “flushable.” Flushable, or non-flushable, wet wipes are manufactured as non-woven sheets of natural and manmade fibres – including cellulosic materials like rayon and/or plastics (Munoz et al. 2018). Wet wipes usually have a high wet-strength, because synthetic fibers retain their form, shape, and strength in a moist state. Maintaining their form, and being strong, are desired properties for wipe manufactures so the product will not fall apart while you use it.

When flushed, wet wipes enter the sewer systems, where they are assumed to move along with wastewater to treatment plants. However, their transport depends on various factors such as pipe diameter and slope, flow rate and velocity, plus the amount of product discharge.

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Wet wipes at a sewer outflow into creek

If a significant amount of flushable wipes are discharged into a sewer system over a short period of time (a few hours), they will accumulate in drains, forming large “white” balls (a.k.a., demon snowballs), and lead to potential sewer backups. Holiday weekends, such as those in summer where people congregate, are an example of times when the amount and frequency of discharge at a single location may increase due to families and friends visiting each other. Likely not something you think about when you convene for a family weekend at the beach!

When we flush our products down the toilet, it absorbs and blends with other waste we send via our households such as food waste, fat, oil and grease (called FOG by plant operators), shampoo, human hair, and cosmetics. When flow is intermittent and low as our household plumbing, flushable wipes settle in our sewer pipes, accumulate over time, and can cause back-ups followed by sewer overflows. At treatment facilities, wipes clog and damage wastewater equipment such as screens, pumps, grinders, mixers, and sensors that require complete replacement or extensive repairs – hence demon snowballs.

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Example of pump blockage from flushed wet wipes

As examples, in England and Wales, approximately 4,000 cases of pipe blockages and property flooding are reported each year (Jeyapalan 2017). In the USA, 400,000 basement backups and 50,000 sewer overflows are documented per year (USEPA 2001). The City of Toronto, Ontario has approximately 10,000 calls a year for reported blockages. Unfortunately, wastewater utilities from around the world have been reporting that wipes are responsible for most pipe blockages and pump clogs in sewer networks. These reports have been published as a series of articles in various languages, and in well-known newspapers such as New York Times (Caron, 2018), The Guardian (UK), and the National Post (Canada).

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Barry Orr holds a mass of wet wipes from a pump station

Consumers assume that “flushable” products must have been tested rigorously for their compatibility with household plumbing and sewer systems. In contrast, there is actually no standard definition of what is flushable, and no standard method to assess flushability. Wastewater engineers are trying to work with governments to help define technical characteristics of flushable products, so that we can clearly differentiate the products that are truly “flushable” from those that are not.

For now, to keep our plumbing “snowball free”, we must not treat wet wipes – whether they say “flushable” or not – like toilet paper. Their size, strength and material composition prevent them from breaking down in wastewater systems, and even if they break down, they may contribute to microplastic pollution in the environment. The bottom line – stop flushing wipes.

Blog written by Barry Orr, spokesperson for Municipal Enforcement Sewer Use Group (MESUG), of Ontario and Faith Karadagli, Associate Professor of Envrionmental Engingeering at Sakarya University, Turkey.

The Decade of Plastic Pollution & Canada’s Leadership

Canada’s recent announcement is a big step forward, but there is still more work to be done

One decade ago, I hopped aboard a research vessel with the Scripps Institution of Oceanography and took my first trip to the North Pacific Garbage Patch. At this time, we had heard about large concentrations of plastics in the middle of the ocean, and about mammals and birds being entangled by large plastic nets and line. What we really understood about plastic pollution ten years ago was just the tip of the iceberg.

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© SCRIPPS INSTITUTION OF OCEANOGRAPHY

As we boarded the ship, we pictured we’d soon be arriving to a large mass of floating debris far from human civilization. We pictured fishing nets, buoys, bags and other large items that could be cleaned up. When we arrived, we saw what the garbage patches really look like. When plastic waste is littered and finds its way to our ocean or even the Great Lakes, it travels with the currents as it’s beaten down by the sun, wind and waves. The plastic that makes its final stop in the garbage patches, 1000s of km out to sea, are mostly small bits of microplastics—the size of a pencil eraser and smaller. Off the bow of the ship, on a sunny and calm afternoon, I saw bits of plastic confetti as far as my eyes could see—making up not a garbage patch you could clean up, but a soup of small plastic debris that could infiltrate every level of the marine food web.

This research expedition, ten years ago, was the beginning of my career quantifying, characterizing and increasing our understanding about the impacts of microplastics in aquatic ecosystems. Today, I no longer spend my time researching plastic pollution in the ocean garbage patches far from civilization; I work with an amazing group of students and collaborators and together we research plastic pollution in rivers, bays, estuaries and lakes—in Canada, the U.S. and abroad. We have never been to a study site where we have not found microplastics in our samples. In fact, some samples have so many pieces we have more than 15 students working on one project.

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Keenan Munno, Tina Wu, Chelsea Rochman, Cassandra Sherlock, and Annissa Ho in the Rochman Lab collaborating on a project to quantify microplastics in the San Francisco Bay. © CAFETERIA CULTURE

This decade, I have been incredibly inspired by the positive change I see around me and the motivation I see by governments around the world to mitigate plastic pollution. This week, I was proud to stand on the shores of Lake Ontario, where we’ve found microplastics in surface waters, sediments, local fish and in drinking water, with the Canadian Minister of the Environment Catherine McKenna and Member of Parliament Julie Dabrusin for an announcement about how Canada will continue to take leadership on the issue.

When I started working on this issue, over one decade ago, it received very little attention from fellow scientists, policy-makers and the public. Today, I am pleasantly shocked everyday by how many people are listening and willing to come together to mitigate the issue.

The announcements made this week by the Canadian Government are a very important step forward, and I’ve been very impressed by the leadership from the Canadian government at working to tackle this issue. There is no silver bullet solution to plastic pollution, and we need solutions that span clean up, reductions in waste and improved materials management. The government has committed to a holistic approach that includes these elements, including research to inform the most effective mitigation strategies.

For this reason, I was thrilled to be invited to share my story and my thoughts on the issue as Minister McKenna made the announcement in Toronto. It was a great opportunity to publicly acknowledge the work Canada has done on this issue including the online portal, the fund for international collaboration, the Ocean Plastics Charter and the support for continued and improved research.

While this is a huge step forward, all should recognize that this is only the beginning and that the work starts here. Everyone across the world has work to do to solve this global issue. As a citizen, we can refuse items that cannot be sustainably managed via reuse or recycling,  reduce the waste we produce and become more waste literate. We can also share our concern with others and write letters to government asking for support.

I intend to continue to work tirelessly on this issue via research through my laboratory at the University of Toronto and through our outreach program—the UofT Trash Team. I spent my last ten years producing data that could inform policy. I am comforted knowing that over the next ten years, the government and all of you will be working right along with me using this new information to inform positive change. This truly is the decade of plastic pollution, and I hope that ten years from now we can all look back on the work we did together and boast about a measurable reduction in the amount of plastic that becomes waste and is littered on the coastlines of Canada and around the world.

Written by Dr. Chelsea Rochman, Assistant Professor at University of Toronto and Scientific Advisor to Ocean Conservancy.

Keeping Canada’s Most Urbanized Watershed Clean

Second Annual “Cleanup the Don” a success

On May 5th, 2019, more than 100 dedicated volunteers grabbed bags to participate in the University of Toronto’s Trash Team’s 2nd Annual Cleanup the Don, a collaboration with the Toronto Region Conservation Authority (TRCA) and Ocean Conservancy’s International Coastal Cleanup (ICC) coordinator in Canada, the Great Canadian Shoreline Cleanup. In conjunction with the TRCA’s annual Paddle the Don event, Cleanup the Don brought members of the community down to the Don River to traverse and conserve one of Toronto’s most important watersheds.

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Trash Team member Sam explores the Don River by paddle © UNIVERSITY OF TORONTO

Stretching nearly 24 miles and spanning more than 88,000 acres, the Don River is one of the largest rivers entering Lake Ontario. The Don River Valley is a popular area for recreational activities, including biking, running, fishing and canoeing. The area is also home to a wide variety of wildlife, including some endangered species like the Redside dace fish and American chestnut tree.

Habitat loss and chemical pollution are major threats to urbanized watersheds like the Don River. Estimates from our most recent University of Toronto Trash Team survey of the river suggest it is also an important route for hundreds of pounds of plastic litter from urbanized areas (like the Greater Toronto Area) to enter the Great Lakes every year.

This year for Cleanup the Don, 107 volunteers spread out across five sites from E.T. Seton Park to Corktown Commons, a six-mile stretch. In all, we removed approximately 550 pounds of plastic litter from the shorelines.

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Top 6 items found during this year’s Cleanup the Don. © UNIVERSITY OF TORONTO

The top six trash items closely tracked what volunteers find during the ICC every year, including cigarette butts (25%), plastic food wrappers (13%), plastic bags and other single-use plastics. We were also surprised to find some unusual items, including a tent and VHS tape cover.

A selection of litter collected during this cleanup was also used to create a mural depicting the Don River Valley. Repurposing litter into artwork can be a great way to raise awareness about how plastic pollution affects your local environment.

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Litter collected during the cleanup was used to create a mural depicting the Don River Valley. © UNIVERSITY OF TORONTO

Since most plastic pollution comes from land-based sources, understanding the sources of plastics in the environment can help us “turn off the tap” or stop the flow of plastics to local waterways like the Don River. Single-use plastic restrictions (such as plastic bag bans) and improvements in waste management can help reduce the number of these items that end up in the environment. Below are five simple actions that individuals can make to help keep plastic from entering the Don River watershed and other waterways:

  1. Reduce your use of single-use plastics! Opt for more eco-friendly alternatives like reusable shopping bags and metal/glass straws.
  2. Clean up your local watershed. Join a local cleanup or start your own. Join Ocean Conservancy on the world’s largest single-day volunteer effort on behalf of the ocean, the International Coastal Cleanup. This year it’s September 21st, 2019. Tips on how to organize a cleanup in your area are available through the Great Canadian Shoreline Cleanup website.
  3. Know your bins! Be aware of which items go in green, black and blue bins. For guidance in the City of Toronto, check out the Waste Wizard app!
  4. Support legislative or community action to reduce single-use plastics and improve waste management in your area.
  5. Educate friends and family about the plastic pollution problem.
Written by Trash Team members Sam Athey, Bonnie Hamilton and Dr. Chelsea Rochman.

Plastic Pollution is Chemical Pollution

How preventing and removing plastic debris mitigates chemical pollution in our oceans

Turtles tangled in fishing nets, whales washed ashore with stomachs full of plastic bags. These are images we, unfortunately, see far too often. But what about the threats you cannot see? Plastic debris is not just a physical threat to marine life, it’s a chemical threat too.

Once in the marine environment, plastics can absorb chemical pollutants from surrounding waters and transport them great distances as they move around with ocean currents. When animals eat plastic, these chemical pollutants can leach into their stomachs, causing toxic effects. Many of these chemicals have been banned from production due to concerns about human and environmental health. However, some are so persistent in the environment that they are still found today.

Plastic products also contain chemical additives such as flame retardants, UV stabilisers and colorants which are added to the plastics during manufacturing. In our ocean, these chemical additives can leach into surrounding waters—posing another potential chemical threat to marine life.

In a recently published paper, we estimated the amount of chemicals that enter the ocean within common single-use plastic items and estimated the amount of chemical pollutants that can be removed from the environment via cleanups.

2018-07-20 14.49.34We looked at some of the most common plastic items found on beaches during the International Coastal Cleanup: beverage bottles, bottle caps, styrofoam foodand drink containers, cutlery, grocery bags, straws/stirrers and food wrappers. Using International Coastal Cleanup data, the average weight of each item, and estimates of mismanaged plastic waste in 2015, we calculated the total weight of each item that entered the oceans in 2015. We then used the percent weight of chemical additives in each item to estimate the mass of chemicals that entered the ocean as a consequence of this plastic debris.

We estimate that combined, these seven plastic items contribute more than 87,000 metric tons of plastic debris to our oceans and carry with them 190 metric tons of 20 different chemical additives. If plastic pollution continues to increase, this value could almost double to 370 metric tons of additives by 2025. This might not sound like very much, but these seven items account for only about 1% of the estimated 8 million metric tons of plastic entering the oceans every year!

Furthermore, we estimated how plastic cleanups contribute to chemical cleanup by removing those absorbed chemical pollutants. For this, we compared coastal and open ocean locations using Hong Kong and Hawaii as coastal case studies and the North Pacific and South Atlantic gyres as open ocean case studies. Here, we focused on Polychlorinated biphenyls (PCBs) because they are commonly found in plastic debris, despite having been banned for decades.

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© HANNAH DE FROND

To estimate total chemical load on plastics in each location, we multiplied the mass of microplastics (g/m2) found in each area by the mass of PCBs found on microplastics (ng/g) in each area. Our results showed that chemical cleanup is more effective on shorelines compared to the open ocean, removing 85,000 times more PCBs in a stretch of coastline in Hong Kong than the same size area of the North Pacific gyre. This might come as a shock, particularly as the gyres are well known to contain large amounts of plastic debris, however, the amount of microplastic per square meter is generally much greater on the shoreline. Although the concentration of PCBs might be high in some open ocean locations, the important factor is how much plastic can be removed per unit area. The more plastic removed, the more chemical removed.

Thus, if we can prevent plastic from entering the environment and cleanup what is already there, we can also mitigate chemical pollution. This reiterates the value of reducing our plastic footprint and participating in coastal cleanups. Cleanup of plastic pollution goes beyond what the eye can see. Cleanup of plastic pollution is also cleanup of chemical pollution!

What Does Your Washing Machine Have to do with Microfibers?

New research suggests microfiber emissions from the wash can be reduced with new technology

Synthetic microfibers are just one of many types of microplastic pollution; however, microfibers are one of the most common types of microplastic pollution that we find in the environment.

Where do they come from? There are likely many sources of microfibers to the environment, and they include clothing, furniture, carpeting, and cigarette butts.

Picture1They are ubiquitous. We find these tiny fibers in samples from headwater streams, rivers, soils, lakes, sediments, ocean water, the deep-sea, wildlife, arctic sea ice, seafood, drinking water and table salt. In our own samples from the Laurentian Great Lakes, our research lab sometimes find more than 100 microfibers in an individual fish. Such widespread exposure raises concerns about effects to wildlife and human health.

But, there’s good news! There are simple solutions to help reduce the number of microfibers that enter our environment each day. Some of these include changing the way we do our laundry–YEP–our laundry.

When we wash our clothing in the washing machine, little bitty fibers come off into the wash water. This is just like when fibers come off our clothing in the dryer and collect in the lint trap. YES, microfibers are indeed a major component of laundry lint! In the washing machine these fibers exit our homes with wash water and travel to a nearby wastewater treatment plant. There, many of them will settle into the sewage sludge, but some will remain in the final treated wastewater effluent that is released directly into local watersheds, lakes and oceans. Although washing our clothes in washing machines is just one source of microfibers to the environment, we know that it’s a significant source. For example, in the city of Toronto, we estimate as many as 23 to 36 trillion microfibers may be emitted to Lake Ontario watersheds each year!

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So, coming back to the solutionswhat can we do about it? Our research group wondered the same thing and decided to test multiple mitigation strategies for washing machines to see just how well they captured fibers in the wash, diverting them away from the environment.

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What did we find? We found that technologies available on the market today work! Upon washing fleece blankets with and without a Lint LUV-R after-market filter (a, pictured above) or a Cora Ball (b, pictured above), we found a significant reduction in microfibers in washing machine effluent. The after-market filter reduced microfibers in washing machine effluent by 87% and the Cora Ball by 26%.

Picture2Our study suggests that these technologies are one effective way to reduce microfiber emissions to the environment. While more studies are needed to understand the contributions of microfibers from other sources and pathways to the environment, we know that washing machines are one pathway for microfibers to reach the environment. Why not help reduce emissions now by changing up your laundry habits today?

For more information, please read our paper published this year in Marine Pollution Bulletin.

Written by Dr. Chelsea Rochman, assistant professor at the University of Toronto and Scientific Advisor to Ocean Conservancy

No Silver Bullet Solution to Plastic Pollution

Evaluating the impact of multiple mitigation strategies to help stem the tide

Plastic pollution has become so pervasive that it is found in seafood, bottled water, beer, table salt and even the air. Hundreds of animals become entangled in discarded plastic debris and fishing gear. Ingestion of plastics by marine organisms can hurt or kill them, and may also be acting as a pathway for the transfer of harmful contaminants through food-webs, with biological implications for all life affected. The economic costs of plastic pollution affecting tourism, fisheries and shipping sectors are estimated to be at least $8 billion USD annually.

Currently, the problem of plastic pollution is being met with a suite of mitigation strategies, such as single-use bans, improving recycling capacity and waste management, substitution of products with “eco-friendly” alternatives and more. These actions are currently being implemented at the national level but the problem is so enormous that the international community has recognized that more action is needed, and urgently. Still, little work is being done to evaluate the impact of these many mitigation strategies being proposed and implemented, and how their impacts will vary in different economic and societal contexts. Without this understanding, we risk wasting vast quantities of money, time, and social and political capital in attempting to preserve the integrity of the world’s ecosystems.

We are the Plastic Pollution Emissions Group

That’s how the Plastic Pollution Emissions Group (PlasticPEG) came about. Based out of the National Socio-Environmental Synthesis Center (SESYNC), the work that we are doing will contribute to improving our understanding of the impacts of these reduction strategies, and inform governments of the most effective ways to contribute to improving the health of our oceans.

With a group of experts from across the world, including some from Ocean Conservancy, we aim to contribute to this knowledge gap by providing science-based evidence of the most effective strategies to reduce the leakage of plastic into our oceans. Our work will build on the inclusion of Plastic pollution in the Sustainable Development Goals (SDGs) and feed into an international agreement to establish a coordinated and effective strategy to drastically reduce plastic emissions into the environment.

How we will make a difference

We are conducting an evaluation of the impact of several plastic pollution management interventions. These include plastic-use reductions, broad-scale investments in waste management infrastructure, the implementation of a circular plastic economy and the cleanup of existing post-consumer plastic waste, including abandoned, lost or otherwise discarded fishing gear from the environment.

We are using ecological modelling techniques and an impact forecasting approach (sometimes referred to as ‘wedges’) to evaluate mitigation strategies at both the country and global level. This means that we can measure how much an action—such as single-use plastics bans—will have on reducing the leakage of plastic into the environment compared to if we did nothing (business as usual). Our analyses will support and inform countries to help them choose the best strategies to reduce plastic pollution, within the bounds of their resource capacity, social context and uniquely local sources of plastic debris.

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Figure 1: Illustrative example of what we aim to assess by combining and comparing different plastic emissions reduction strategies and scenarios. © STEPH BORRELLE

If we are to achieve meaningful reductions of plastics in our oceans, we need to have a toolbox of effective solutions that can be implemented at multiple geographic scales, economies and levels of governance. The aim of the Plastic Pollution Emissions Group is to help find those solutions in a meaningful way.

For further information, please visit plasticpeg.org or follow us on Twitter @PlasticPEGroup.

Written by Steph Borrelle, a Smith Postdoctoral Fellow in Conservation Biology and Dr. Chelsea Rochman, an Assistant Professor at the University of Toronto and Scientific Advisor to Ocean Conservancy

Discovering the East Don

Cool temperatures didn’t stop our team from keeping rivers clean

On November 10 our team joined Toronto Region Conservation Authority (TRCA) to clean a portion of the East Don Trail in Charles Sauriol Conservation Area. You might not think of organizing a cleanup in November, but litter season is year-round so it was important for our team to head to a local shoreline in the city to make a difference. It was a chillier cleanup than usual however the results indicated trends we are all too familiar with, single-use items scattered on the shoreline, many of them plastic.

Our team of 20 were eager to get out there and see what type of items we could remove, and we were amazed at the quantity of what we found. Our team also filled out a brand audit to uncover not only what items were most commonly found as litter, but (when identifiable), which brands came across.

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Trash Team members Susan and Rafaela carefully document litter found

A total 138 lb of litter was removed, and our top 10 items included a selection of single-use plastic items we see at many shorelines in the city, including cigarette butts and many items such as bags, bottles and food wrappers. Coffee cups were also found during the cleanup, which might not sound like a plastic material, but due to their lining of polyethylene we consider them as such. This lining means coffee cups are a challenging item to recycle and instead should swapped for reusable alternatives, like a stylish travel mug!

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Most common litter items found along the East Don. © UNIVERSITY OF TORONTO

Thank you to TRCA for inviting us to join your team for the day, we had a really had a fun time and enjoyed getting to know another section of the Don River watershed. We’re already looking forward to more cleanups with our team and members of the public.

To hear the TRCA perspective on this cleanup, please visit their blog. While you’re there, visit their website to learn more about the East Don Trail project. To lead your own cleanup, visit the Great Canadian Shoreline Cleanup to register your event.

Written by Susan Debreceni, Outreach Assistant for the U of T Trash Team.