What we learned by counting our household waste

2022 Home Waste Audit Reflections

Winter is in full swing and school is officially back in session! To kick off the new year, members of the U of T Trash Team joined the Home Waste Audit, a 4-week journey to count and categorize household waste with the goal to reduce how much you are throwing away.

From January 19th to February 15th, participants sorted, counted and took actions to reduce waste at home. Here’s what some of us had to share about our experience.

Zoe: Conducting the Home Waste Audit during the re-opening of Ontario meant an increase in social interactions and I found reducing waste in social gatherings was tough. However, at the start of my Home Waste Audit I was fortunate enough to meet fellow U of T Trash Team volunteer, Lisa Erdle, while skating on Lake Ontario near the Toronto Islands.

Lisa and her partner Brendan were very kind and shared homemade treats and hot cocoa, a delicious no waste option. This act of kindness inspired me to also plan ahead when hanging out with friends, by making shareable baked goods instead of buying pre-packaged snacks like granola bars or hot drinks in takeout cups. 

Having grown up in sunny Malaysia, waste management had some differences. Recycling services were not widely offered like they are here, and there were no blue bins or composting green bins that got conveniently picked up outside houses. Instead, I remember making regular trips with my parents to recycling centers to dispose of our recyclables. The Toronto Waste Wizard has been my best friend over the duration of the Home Waste Audit. Currently in my 4th year as an undergraduate studying materials science, the process of learning about material recyclability has been fascinating to me. I’m hoping to continue to learn more about the materials we use in our daily lives and the natural alternatives on the rise to replace plastics.

Grocery basket filled with loose vegetables, fruit, canned items and plastic packaged food items.

My grocery basket is not perfect, but I tried to reduce packaged food items. 
(Photo credit: Zoë Ungku Fa’iz)

Ludovic: The Home Waste Audit was an opportunity for me to take back old habits I had before COVID-19, like using my own travel mug when going for coffee, buying in bulk, and bringing my own bags for veggies at the grocery store.

Unfortunately, my partner and I got sick (with COVID-19) during the Home Waste Audit and this had some consequences to our waste! Rapid antigen tests accounted for some surprise but unavoidable waste. For every test completed, at least 5 items entered the trash bin and every time we used a tissue these went into the garbage bin instead of the green bin. In addition, being stuck home left us little choice but to buy groceries online, which resulted in more packaging than usual. For example, we received some veggies in plastic wrapping, something we would normally avoid.

Recycling items such as envelopes, boxes, toilet rolls, food packaging, containers, glass bottle, cans and cartons on floor.

A week of recycling items, classified by material type (Photo credit: Ludovic Hermabessiere)

It is important to highlight the ways COVID-19 modifies our lives, including the challenge it presents for those aware of the environmental issue of plastic and who are trying to reduce waste at home. In spite of these challenges, we were able to change a few of our habits in the final week and the knowledge learned will help us continue to decrease our waste.

Jane: I live with my sister and we adapted some basic waste reduction habits years ago, such as bringing our own travel mugs to the coffee shop, using tote bags for groceries and using reusable produce mesh bags. Even though we reduce waste where we can, we still accumulate trash from areas including food packaging, personal-use products, and deliveries. The Home Waste Audit helped me clearly see how much waste I produce weekly and identify the areas in which I can improve. For example, when gathering with friends, I now plan to bring homemade snacks instead of buying chips and fruits in excess packaging.

Items from the landfill bin are ready to count and categorize. (Photo credit: Jane Kartasheva)

It’s very easy to end up throwing out more than necessary if you don’t know how to sort waste properly, and the TOwaste app was an amazing resource! Did you know that paper towels go into green bin but if they are soiled with chemicals – the garbage bin? This is one of the many things I learned by paying closer attention to waste sorting. I will continue to educate myself about waste management in Toronto and discover new ways to reduce my footprint.

Emily: My dog Ara and I found the Home Waste Audit to be both fun and challenging! Before moving to Toronto, we lived in Northern Yukon where we didn’t have many options when it came to refillables or bulk stores.* This process reminded me of the different options and small businesses to support in the city, like one of my favourites, Nuthouse, where you can refill food products like oatmeal and nuts in bulk. Breaking habits of online ordering, especially in the pandemic can feel very hard, so the Home Waste Audit was a great reminder to support local businesses, especially ones so near to my home!

Ara sorting our recycling. (Photo credit: Emily Chudnovsky)

I also enjoyed reading Rachel Salt’s books on the impacts of plastic and how to reduce your own plastic footprint, The Plastic Problem and Your Plastic Footprint: The Facts about Plastic Pollution and What you can Do to Reduce Your Footprint. I’m very glad to have done the Home Waste Audit, as having to consider every piece of waste I produced gave me a chance to think about different ways to make less of it! 

Great books by Rachel Salt, borrowed from the Toronto Public Library! (Photo credit: Emily Chudnovsky)

Within a short 4-week period, members of our team gained a better understanding of how our environments can have an impact on our habits. By sorting through our waste, we have learnt about the resources available – online and in our own neighbourhoods – to reduce and rethink the items we use daily. If you feel inspired to try your own Home Waste Audit, head over to this page to get started!

Compiled by Zoë Ungku Fa’iz, Materials Science undergraduate student, with submissions by U of T Trash Team members Ludovic Hermabessiere, Jane Kartasheva and Emily Chudnovsky.

*Though in Dawson we did have access to an incredible “Free Store,” an initiative from the communities’ not-for-profit recycling depot where everyone brought pre-loved items for others to enjoy. After doing a bit of research I found the instagram page, Stooping Toronto (@stooping_toronto), it’s got tons of great items to be treasured by a new home! 

Plastiques – un cocktail chimique

La pollution plastique n’est pas seulement une affaire de particules mais aussi de produits chimiques !


Chacun d’entre nous utilise du plastique dans sa vie de tous les jours. Ce que peu d’entre nous ne savent pas, c’est comment cette matière est fabriquée et à quel point cette fabrication implique l’utilisation et l’ajout de produits chimiques.

Qu’est-ce qu’un additif plastique ?

Le plastique est un polymère synthétique fait à partir de chaînes répétées de molécules appelées monomères. Chaque type de matière plastique comme le polyéthylène (utilisé pour fabriquer les sacs plastiques) ou le polypropylène (utilisé pour fabriquer les pots de yaourts) sont des polymères différents. Durant la fabrication, les monomères sont liées les uns aux autres dans un processus appelé la polymérisation. À ce stade, des produits chimiques sont ajoutés afin de donner aux plastiques des propriétés spécifiques comme la flexibilité, la durabilité ou la couleur des plastiques. Ces produits chimiques sont communément appelés les additifs plastiques.

La polyvalence du plastique est majoritairement liée à la présence d’additifs plastiques dans cette matière. Par exemple, les plastiques présentent une forte palette de couleurs liée à l’utilisation de colorants et ces derniers sont flexibles grâce à l’utilisation de plastifiants. Ces deux propriétés sont deux aperçus parmi tant d’autres. Il existe de nombreux différents types de plastiques qui sont utilisés pour créer une multitude de produits ayant des applications diverses, chacun ayant sa propre combinaison d’additif plastique, résultant en un grand nombre de molécules utilisées comme additifs plastiques.

Un poisson créé avec des déchets plastiques récoltés sur une plage française (Équihen-Plage). Les plastiques utilisés ici comprennent une variété de couleurs, formes et usages. Il est possible d’y voir des mousses, des bouchons, des morceaux de filets de pêche et des bâtons de sucettes. Ceci met en évidence la diversité de la matière plastique pour laquelle les additifs plastique jouent un rôle important. Crédit photographique : Ludovic Hermabessiere.

Il est important de savoir que ces additifs plastiques ne sont pas liés chimiquement aux polymères plastiques (pas de liaisons covalentes) ayant pour conséquence la lixiviation (relargage) de ces produits chimiques du polymère lorsque les conditions environnementales sont propices. Les additifs plastiques peuvent être ainsi disponibles dans l’environnement et accessibles pour les organismes vivant dans celui-ci. Si les additifs plastiques sont toxiques, ceci peut être un problème pour l’environnement.

Pourquoi étudier les additifs plastiques ?

Les plastiques se retrouvent dans l’environnement où ils se dégradent et forment des particules de petites tailles. Les plastiques ayant une taille inférieure à 5 mm sont appelés des microplastiques. Ces microplastiques, comme d’autres objets plastiques de plus grandes tailles, peuvent être ingérés par des animaux et avoir pour conséquence un faux sentiment de satiété, la suffocation et dans certains cas extrêmes ils peuvent causer la mort de l’animal. Ces effets peuvent être catégorisés comme « physique » car ici la taille ou la forme de l’objet plastique ingéré est à l’origine des conséquences. Les additifs plastiques quant à eux peuvent être relargués des plastiques dans les animaux lorsque ceux-ci ingèrent ces microparticules créant ainsi un effet additionnel lié aux produits chimiques. À ce jour, peu de recherches ont été effectuées pour comprendre d’où venaient les effets liés aux microplastiques car il est complexe de distinguer les effets « physiques » des effets « chimiques ».

Néanmoins, certains scientifiques ont mis en évidence des effets « chimiques ». Dans une étude, des chercheurs ont exposé des poissons de récifs coralliens (Pseudochromis fridmani) aux produits chimiques dans deux sacs plastiques fait du même polymère. Ces chercheurs ont démontré que les additifs plastiques d’un des deux sacs plastiques avaient provoqué la mortalité des poissons, mettant en évidence que la composition en additif plastique varie d’un produit à un autre. Dans une autre étude, les effets observés sur des daphnies (Daphnia magna) étaient dus soit aux effets « physiques » soit aux effets « chimiques » ou les deux combinés après exposition des daphnies à différents polymères plastiques. Ces deux études montrent, qu’il est nécessaire de comprendre la contribution des effets « physiques » et « chimiques » dans la toxicité liée aux microplastiques sur les organismes.

Comment j’étudie les effets des additifs plastiques ?

Je réalise des expériences au laboratoire et en milieu naturel pour répondre aux questions sur le rôle des additifs plastiques dans la toxicité des microplastiques.

Au laboratoire, j’ai récemment exposé des poissons (Tête de boule (Pimephales promelas)) à des microplastiques contenant des additifs, des microplastiques sans additifs et des additifs seuls. J’ai utilisé du polyéthylène qui a été fabriqué spécifiquement avec ou sans additifs plastiques pour réaliser ces expériences. Les différentes conditions d’exposition de cette étude vont me permettre de mettre en évidence si les effets des microplastiques sont « physiques » et/ou « chimiques ». Les effets seront observés sur la croissance, la survie et l’expression génique chez les poissons. De plus, la concentration des différents additifs plastiques sera déterminée dans les tissus des poissons.

Aquariums contenant les poissons têtes de boules de l’expérience au laboratoire. À la surface des trois premiers aquariums (au premier plan), des particules sont visibles. Les aquariums les plus à gauche et droite contiennent le polyéthylène avec additifs (couleur jaune) alors que l’aquarium du milieu contient le polyéthylène sans additifs plastiques (couleur transparente). Crédit photographique : Ludovic Hermabessiere.

Pendant l’été 2021, des expériences en milieu naturel ont eu lieu dans la Région des lacs expérimentaux (Experimental Lakes Area). Neuf enceintes ont été déployées dans un lac boréal au Nord-Ouest de l’Ontario au Canada. Chaque enceinte avait des poissons, perches jaunes (Perca flavescens), qui ont été exposés à des concentrations différentes et croissantes de microplastiques (polyéthylène, polystyrène, polyéthylène téréphtalate) contenant des additifs plastiques. Nous avons déployé des échantillonneurs passifs dans l’eau afin de quantifier la lixiviation (relargage) des différents additifs plastiques et nous avons aussi échantillonné les poissons à la fin de l’expérience afin de mesurer la quantité d’additifs plastiques dans leurs tissus. Les perches jaunes seront aussi analysées pour d’autres paramètres comme l’expression génique, le profil d’acides gras, croissance et survie, nous permettant ainsi d’avoir une meilleure idée de l’influence potentielle des microplastiques sur la santé de cette espèce de poisson.

Une équipe de recherche ajoutant des microplastiques dans l’enceinte contenant les poissons lors des expériences réalisées à la région des lacs expérimentaux. Différents microplastiques sont visibles à la surface : polyéthylène (jaune), polystyrène (rose), polyéthylène téréphtalate (bleu). Crédit photographique : Scott Higgins.

Ces expériences informeront sur la manière dont les additifs plastiques peuvent lixivier des microplastiques et ainsi que sur les impacts possibles sur la santé de différentes espèces de poissons. Ce travail comblera une lacune concernant la complexité de la pollution par les plastiques, celle-ci étant probablement plus qu’un effet « physique » mais aussi un cocktail « chimique ».

Écrit par Ludovic Hermabessiere, chercheur post-doctoral travaillant sur le devenir et les effets des additifs plastiques et Chelsea M. Rochman, Professeure assistant à l’Université de Toronto, co-fondatrice de l’U of T Trash Team et Conseillère Scientifique d’Ocean Conservancy. Les auteurs remercient Dyana Ouvrard pour l’assistance dans la création de la version française de l’article de blog.

Ce travail a été réalisé grâce au support financier d’Environnement et Changement climatique Canada via l’Initiative visant à accroître les connaissances sur la pollution plastique

Plastics – a chemical cockTALE

Plastic pollution is more than particles – chemicals are in there too!


We all use plastic in our everyday life. I’m currently writing this post on my laptop. What most of us don’t know is how this plastic material is made and what chemicals it might contain.

What is a plastic additive?

Plastics are synthetic polymers made from a chain of repeating molecules, called monomers. Each plastic type, such as polyethylene (used to make plastic bags) and polypropylene (used to make plastic yogurt containers), are different polymers. During manufacturing, monomers are strung together during a process called polymerisation. At this stage, some chemicals are added to give plastic specific properties, such as adding flexibility, durability and/or color. These chemicals are called plastic additives.

The properties, that make plastic a versatile material, are there because of the plastic additives. Plastics gain color from the addition of chemical dyes, flexibility from plasticizers, UV-resistance from antioxidants, and so on. There are many different plastic types, which are used to create many different products, each with their own additive chemicals, making the overall number of plastic additives on the order of thousands of molecules.

A fish crafted with plastic litter found on a French beach (Équihen-Plage). Plastic used here, encompasses a lot of varieties of colors, shapes and purposes. Some foam, bottle caps, fishing line, and lollipop sticks are visible, demonstrating the diversity of plastic material. Additives help shape the diversity of these plastic pieces. Credit: Ludovic Hermabessiere

It is important to note that these plastic additives are not chemically bound to the polymer, meaning that they can leach from (or leave) the plastic product. This allows the plastic additive to become available to living things in the environment. This may be a problem, if the additive chemical can be toxic.

Why study plastic additives?

Plastic products do find their way into the environment where they undergo degradation into every smaller particles. Plastics smaller than 5 mm in size are called microplastics. Microplastics and larger plastic objects can be eaten by animals, which can result in a false feeling of fullness, suffocation and even death. Such effects can be categorized as physical, because the shape and size of the ingested particles is leading to a consequence. Plastic additives leaching into an animal can have an additional chemical effect. To date, little research has been done on the chemical effects of microplastics because it is complicated to distinguish between physical and chemical effects.

Still, some scientists have demonstrated a chemical effect. In one study, researchers exposed coral reef fish (Pseudochromis fridmani) to chemicals from two different plastic bags. They found that chemicals from one of the bags led to mortality, highlighting that plastic additive composition varies from product to another. In another study, researchers showed that toxicity to water fleas (Daphnia magna) can be caused by both the additives and the particles themselves (i.e., physical and chemical). These studies show more work is needed to understand these effects, and particularly those from additive chemicals.

How do I study additives effects?

I use laboratory and field experiments to answer questions about the role of additives in microplastic toxicity. In the laboratory, I exposed fish (fathead minnow (Pimephales promelas)) to plastic with additives, plastic without additives and additives alone. I used polyethylene, and had it specially made with and without additives. Here, the different conditions allow me to assess whether effects are physical and/or chemical. I looked for any effects related to growth, survival, and gene expression. I am also measuring the bioaccumulation from the additive chemicals.

Tanks containing fathead minnow in the laboratory experiment. At the surface of the three tanks up-front, plastic particles can be seen. The ones to the left and right are polyethylene with additives (yellow color), and the one in the middle is clear polyethylene with no additives (clear in color). Credit: Ludovic Hermabessiere.

Field experiments began in Summer 2021 at the Experimental Lake Area. Nine in-lake enclosures were deployed in a boreal lake in Northwestern Ontario, Canada. Each enclosure had yellow perch (Perca flavescens), which were exposed to different and increasing concentrations of a mix of microplastics (polyethylene, polystyrene and polyethylene terephthalate) loaded with plastic additives. We deployed passive samplers in the water that enable us to quantify the leaching of the different additives and also sampled to measure any bioaccumulation (or the uptake of these chemicals into their tissues). Fish will also be assessed for toxicity, including gene expression, fatty acids profiles, growth, and survival allowing us to have a broader understanding of how (and why) microplastics alter fish health.

Research crew adding microplastic at the start of the field experiment in one enclosure at the Experimental Lake Area. Different microplastics can be seen: polyethylene (yellow), polystyrene (pink) and polyethylene terephthalate (blue). Credit: Scott Higgins.

Overall, both experiments (in the lab and field) will inform how plastic additives leach from microplastics and will inform how plastic additives affect fish. This work fills a critical gap in our understanding about the complexity of plastic pollution – which is more than just a physical particle; it’s also a chemical cocktail.

Written by Ludovic Hermabessiere, postdoc researcher in the Rochman Lab working on plastic additives fate and effects and Chelsea M. Rochman, Assistant Professor at University of Toronto, co-founder of the U of T Trash Team, and Scientific Advisor to the Ocean Conservancy

This work was undertaken with the financial support of Environment Climate Change Canada through the Increasing Knowledge on Plastic Pollution Initiative.

A Tale of Tagging Trash

Oh the places they’ll go!

Over this past summer, while you were walking along the waterfront, taking a ferry to Centre Island, or swimming at Cherry Beach you may have encountered bright orange water bottles drifting aimlessly through Toronto Harbour, but these water bottles weren’t litter – they were research! We, the U of T Trash Team, launched the Tagging Trash project in collaboration with PortsToronto, Toronto Region Conservation Authority, Ontario Ministry of the Environment, Conservation and Parks, and University of Toronto Scarborough, to learn how plastic litter travels in our harbour. Throughout April to August, we released orange GPS-tracked bottles from various points across the Toronto Waterfront, Harbour, and Islands. You may be asking, “Why? Isn’t this making plastic pollution worse?” The answer is, we are actually working towards solving our plastic problem. Plastic pollution in our waters causes harm to wildlife and tarnishes the beauty of our lake. To address this problem we first need to understand where litter comes from, where it travels, and how long it takes for litter to reach its final destination. Through our research, we were able to collect valuable data that reveals the way floating plastic litter travels in our harbour and where we need to place cleanup technologies like Seabins!

So, HOW did we do this?

Step 1: Designing the tracker bottles

Why water bottles? Plastic bottles are a common litter item found along shorelines. They are also large and buoyant, which makes them the perfect housing for our Globalstar IoT Satellite Trackers. We also needed to ensure that our GPS trackers were always facing the sky to provide us with the most accurate GPS coordinates – and these bottles were an ideal shape for adding the necessary weight to act as ballast and keep the trackers facing skyward.

To try to prevent people from mistaking our bottles as trash (more on this below), we posted signs about our project and labelled each bottle with clear messaging that they were for research with a QR code linked to our website. We also publicized our Tagging Trash project through social media and the local news.

Step 2: Selecting deployment locations

To get realistic information regarding how litter moves in the harbour, we released bottles from areas that are likely sources of plastic litter based on Visual Audits conducted in the summer of 2020, visitor hotspots, and scientific studies of water movement within the harbour. Overall, we picked 13 locations, ranging from Bathurst Quay, Keating Channel, the tip of Tommy Thompson Park, and the Toronto Islands.

The Tagging Trash initial (yellow) and final (magenta) positions in Toronto Harbour (Google Earth (2021) Toronto Harbour, 43°38’20”N, 79°22’20”W).

Step 3: Tracking where the bottles went

After observing how the bottles traveled over a period of 4 months, we learned that litter gets into the nooks and crannies of our waterfront. Anywhere we found our GPS-tracked bottles, there were hundreds of pieces of litter. Our bottles also revealed some really interesting movement patterns.

Having a nice view depends on where you look, eh? Bottle floating in and out of the Pirates life dock at Bathurst Quay.

Trendy Trackers

Most of our bottles quickly travelled through Toronto Harbour for about one kilometer before becoming trapped or stranded on shore within a day of being deployed. These bottles, which have similar trends in travel, were typically recovered from sheltered areas like slips, bays, and under piers, docks, and boardwalks. This information lets us and policy makers know that most of the trash in the harbour likely comes from Toronto. Litter which makes its way into the middle of the harbour tends to move with the prevailing winds toward the Keating Channel and the shipping channel. This is concerning because we suspect that plastics can be hit by boats and broken into smaller pieces of plastics, expediting the formation of microplastics. More trash capture devices and local trash cans with lids will reduce the litter in Toronto Harbour and prevent the formation of microplastics.

Above is a wind rose which shows the directions from which wind travels in Toronto Harbour. The longer bars indicate that winds blow more often while the colour corresponds to wind speeds. For the summer of 2021, the prevailing winds blew from the west/west-southwest nearly 25% of the time and there were several storms that brought in strong winds from the east.The observed westerly prevailing winds help keep litter in Toronto Harbour.

Bottles became trapped under city infrastructure or stranded onshore once they reached areas sheltered from the wind. Occasionally, large waves from storms would strand bottles on land and prevent them from travelling within the harbour. Some bottles, however, were a little more adventurous.

Escape artists

While most of our bottles stayed in the harbour, the ones that escaped the harbour left through the Western Gap more often than the Eastern Gap, and would soon beach. To test if trash from Toronto’s popular beaches could travel farther into Lake Ontario, bottle “John Tory”, from deployment 3, was deployed from the southern end of Center Island. During its 300 km journey, it spiraled its way to Ajax. The spiraling path demonstrates the Coriolis effect from Earth’s rotation. A more adventurous bottle, Onitariio, was released from the tip of Tommy Thompson Park to test if litter east of the harbour is likely to travel into the harbour. Remarkably, this bottle  travelled across Lake Ontario for 300 km until its batteries ran out of charge near Rochester, NY.

Bottle “Onitariio” (yellow) from our April test-deployment was released from Tommy Thompson Park and had travelled past Rochester, New York. Bottle “John Tory” (pink) from our third deployment had travelled from Center Island and beached in Ajax.

Couch potatoes

Some bottles weren’t big on travelling and were retrieved only a few dozen meters from their deployment locations. They became stuck under the boardwalks near Harbour Square Park West and were, unfortunately, not reachable by powerboat; we had to retrieve these trackers by kayak! While retrieving them, we found hundreds of pieces of litter from clothing, boating gear, food containers, and many microplastics. These hard to reach areas could use passive trash capture devices (like Seabins) to make litter collection more feasible.


We observed several of our bottles travelling up into the Keating channel, and past the floating boom at the mouth of the Don River, which had been installed to prevent trash from flowing down the Don River and into Toronto Harbour. This movement surprised us because we didn’t expect our bottles to travel against the water current, but we later discovered that the winds were strong enough to push our bottles upstream. This information suggests the need to improve the effectiveness of “leaky” booms.

Other bottles that surprised us were those that ended up in garbage cans, despite our outreach attempts. This made for some interesting fieldwork; we found ourselves digging through garbage cans like raccoons when searching for our bottles. Although losing trackers to the garbage was frustrating at times, it showed that Torontonians care about the environment and feel a responsibility to keep their waters clean and plastic-free. We also saw, in real-time, the pathway our litter takes once thrown away – it heads to our city landfill located in London, Ontario!

We rescued some of our tracker bottles from the trash, can you spot one in this trash bin?

Step 4: Analyzing our findings

Overall, we had a ton of fun and learned a lot about how litter moves within our waterfront. We found that most of our litter likely stays in our own backyard. With the exception of a few sneaky bottles, most quickly accumulated in nearby sheltered slips, piers and embayments. Patricia Semcesen continues to work on this project and analyze our data which she will use to develop a hydrodynamic model that will help understand and predict the transport of plastic litter in Toronto Harbour.

Once the hydrodynamic model is developed, its results will inform where future trash captures devices should be placed to prevent litter from escaping into Lake Ontario. This information will also help in improving waste-management infrastructure, and encourage  environmentally-friendly initiatives to reduce plastic litter locally, like bring-your-own reusable container and cutlery discounts. It can also tell us where regular cleanups should be organized to pick up trash from hard to reach places (like beneath boardwalks and docks) where trash capture devices can’t be placed. Along with collecting valuable data, we also found the Tagging Trash project a great tool for outreach and communication surrounding waste literacy both locally and globally. We hope to inspire groups across the world to initiate their own projects to better understand the fate of plastics in their waterways.

Written by Cassandra Sherlock (top), Former Community Outreach and Research Specialist at the U of T Trash Team, and Patricia Semcesen (bottom), Environmental Science PhD student at the University of Toronto, Scarborough.


We would like to thank everyone who assisted in making this project a success which includes our U of T Trash Team volunteers: Lisa Erdle, Brendan Carberry, Emily Darling, Madeline Milne, Ludovic Hermabessiere, Rachel Giles, Hayley McIlwraith, Su’aad Juman-Yassin, and Ariba Afaq, from GlobalStar Martin Jefferson, from TRCA, Laura Salazar, Matthew Fraschetti, Kirstin Pautler, Samuel Burr, Mark Wilush, Connor Hill, Brynn Coey, Brian Graham and Angela Wallace, from PortsToronto, Micheal David, Chris Sawicki and Jessica Pellerin, from MECP Bogdan Hlevca, from U of T, Matthew Wells, Chelsea Rochman, Rafaela F. Gutierrez and Susan Debreceni. We’d also like to thank our funders: Environment and Climate Change Canada and National Geographic.

I don’t eat fish guts, so do I really eat microplastics?

Our study suggests yes, but not many.

We all use plastic at least once a day. It’s everywhere. It’s in the laptop I’m using to write this blog, it’s in the clothes I’m wearing as I sit at my desk, and it’s in the packaging protecting the food I bought from the grocery store. It’s easy to see how much we rely on plastic. But what we don’t see is that this widespread dependence on plastics has led to widespread contamination of microplastics – tiny pieces of plastic (< 5mm in size) that float in the air around us and lurk in the food we eat and water we drink.

Recently, researchers in the Rochman Lab and collaborators at the Ontario Ministry of the Environment, Conservation and Parks sampled seven species of sportfish from Lake Simcoe – situated in Ontario, Canada. With these fish, we were trying to understand how much microplastic they were eating and whether these particles were also present in the fillets that we eat. To do this, we looked for microplastics in the stomach, fillet and liver of each fish. Our study revealed that microplastics were present in the stomachs of nearly all of the fish sampled, and this did not come as a surprise, given a recent study where we demonstrated relatively high concentrations of microplastics in several species of fish from Lake Ontario and Lake Superior.

However, we also found microplastics were widespread in the fillets and livers of all seven species. This means that plastics are not just being excreted after being ingested (i.e., via poop), but they’re also travelling to other parts of the body – including the parts we eat. 

Lead author, Hayley McIlwraith, looking at the microplastics found in the tissues of fish from Lake Simcoe in Ontario, Canada.

Previous research has suggested that microplastics can transfer from a gut to a fillet, but here we show widespread occurrence in wild fish. Around 74% of fillets and 63% of livers had at least one microplastic present, while 99% of fish had at least one particle present in any of the three studied tissues.

Now before raising the alarm bells and cutting fish out of your diet, keep in mind the levels we found were low relative to other sources of microplastics we may be exposed to. In our study, we calculated the yearly intake of microplastics based on a diet of eating half a pound of fish twice per week. For most of the fish species in our study, average consumption would be less than 1000 microplastics a year.

A graph showing the annual intake of microplastics by humans based on a diet of 0.5 lbs of fish twice per week. This is based on data from our study.

In comparison, another study estimated that 35,000 – 62,000 microplastics are inhaled annually by the average adult. These other exposure routes include drinking water, beer, salt and even honey. All of this raises questions about the many routes of exposure, and how microplastic contamination relates to risk for humans.

Average number of microplastics humans are exposed to from multiple sources.

But that’s not all, we found something else that was really interesting. For seafood, we are used to being advised about how much to eat in our diets due to contamination from organic chemicals – such as mercury or PCBs. We are generally told to eat fewer top predators or long-lived fish, because these fish tend to have higher levels of these toxins. In this study, our data suggests the opposite may be true for microplastics. We found that while larger fish contained a higher number of microplastics overall, it was the smallest fish that contained more microplastics per gram of tissue. So, if you cut a piece of fillet of the exact same size from the largest fish and from the smallest fish, the fillet from the small fish would have more pieces of plastic inside it. These results highlight the uniqueness of microplastics as a contaminant – i.e., they are physical particles rather than dissolved organic chemicals, and thus may behave differently than chemical contaminants. These unique properties are important, especially when considering their risks and effects in the environment.

The uniqueness of our results opens up new avenues of research relevant to the fate and risks of microplastics in food webs. Don’t worry, members from our lab are already on it! A current project is looking at fish fillets from Lake Ontario, where we already know fish have lots of microplastics in their guts – some up to 900 particles!

Of course, knowing that these small plastics are getting inside our bodies is scary. And we don’t yet know what that means for us. Luckily, there are many researchers already looking into the effects on humans. But just like fish excrete most plastics, we likely do too.

Overall, this study raises many more questions than it answers and until then, we need to reduce our plastic waste, reuse as much as possible and recycle when we can. Each of these actions will reduce plastic emissions to the environment and reduce plastic exposure for us.

Written by Hayley McIlwraith, Research Assistant in the Rochman Lab and Chelsea Rochman, Assistant Professor at the University of Toronto, co-founder of the University of Toronto Trash Team and Scientific Advisor to the Ocean Conservancy.

The Collective Power of Trash Traps

These local solutions tackle global plastic pollution

Plastic pollution in freshwater and marine ecosystems is increasing across the globe. Last year, it was estimated that roughly 30 million tonnes of plastic waste entered our aquatic ecosystems. If we continue business as usual, this number may increase as much as three-fold by 2030—in less than one decade.

There is no time to waste, and we all must do our part

To prevent the devastating impact of plastic pollution, we must implement diverse mitigation strategies today, including reduction of plastics, more sustainable waste management and cleanup. Even as countries ban single-use plastics and increase their waste management, cleanup will continue to be an essential part of the solution toolbox. And if we really want to significantly reduce the amount of plastic ending up in our waters, then we must increase our level of cleanup by orders of magnitude—in order to meet our target cleanup goal at least 1 billion people would have to participate in Ocean Conservancy’s International Coastal Cleanup each year. So how can we increase our cleanup effort, and do it substantially?

The answer, in part: trash trapping technologies! These devices work around the clock to make a huge impact: Mr. Trash Wheel in Baltimore harbour can collect up to 38,000 pounds of trash in a single day. Not only do they help us remove plastic directly from our waterways, but they are also a research tool. By collecting data, like the types and amount of plastics these devices capture, we can quantitatively measure our impact and inform local source-reduction. They are also an incredible way to raise awareness and can easily become a centrepiece for education and outreach, like Mr. Trash Wheel, who inspires imagination and local solutions in the Baltimore community.

Mr. Trash Wheel celebratory floatilla in the Baltimore Harbour. Photo courtesy of the Mr. Trash Wheel Twitter handle.

Together, the U of T Trash Team and Ocean Conservancy are developing a trash trapping network to increase the impact of the International Coastal Cleanup. We aim to bring together stakeholders from across the world with a shared interest in the collective power of trash traps to share data and best practices. To launch our network, we are hosting a virtual workshop, along with PortsToronto, that is free and open to the public.

Part of our mission is to work locally to make a difference globally. At our “Trapping Trash and Diverting it from our Waterways” workshop, we aim to motivate local groups of stakeholders to come together to form a more impactful, global collective. We will provide the recipe for success, and share our tools for harmonized data collection to enable each team to quantify their individual impact and share it within the International Coastal Cleanup global database.

If we truly combine our efforts to strengthen the volume of plastic waste cleaned up around the world, we can make a measurable difference. And we can do it better together.

Written by Chelsea Rochman, Assistant Professor at the University of Toronto, co-founder of the University of Toronto Trash Team and Scientific Advisor to the Ocean Conservancy.

Ring in the New Year with LESS WASTE

This New Year we think everyone will be happy to say goodbye to 2020 and hello to 2021.

With the new year approaching, there is an opportunity for setting new personal goals and of course – New Year’s Resolutions!

This year rather than vowing to exercise more, save money, or maintain a healthier diet, why not try reducing your household waste and increasing your waste literacy?

At the U of T Trash Team these goals are our mission, and this New Year’s we want to help you make positive changes your waste habits. How? Through our Home Waste Audit!

During the Summer of 2020, we ran a Home Waste Audit as part of Plastic Free July.  This audit was so successful that we decided to bring it back for New Years. So, if you’re looking to reduce your household waste in 2020  – join us!

What can you expect? The Home Waste Audit will run over the course of four weeks, from Wednesday January 13 – Tuesday February 9, with an introductory webinar on Tuesday January 12 (and results Tuesday February 23). Throughout, we will be there providing all the tools you need to learn more about your local recycling guidelines, ways to reduce your landfill waste, and of course, ways to reduce your plastic waste.

See below for a summary of results from July and examples of weekly waste. Participants spanned 2 countries, 4 provinces/states, and 8 cities.

Increasing our waste literacy is empowering. It enables us to make smart choices about the materials we buy, how we use these materials, and what we do with them once we when they reach end-of-life. Combined, these smart choices reduce waste and protect our environment.

Together let’s make 2021 a better year, with a common goal to reduce excess waste one item at a time, one household at a time. Start the year off right, with us, building habits that can last for many years to come.

If you have any questions about the Home Waste Audit or how to take part, please contact us at UofTTrashTeam@gmail.com. We hope to see you soon!

Written by Chelsea Rochman; Assistant Professor at University of Toronto, co-founder of the U of T Trash Team, and Hannah De Frond, Research Assistant in the Rochman Lab and member of the U of T Trash Team.

Putting Seabins on Toronto’s Waterfront – Capturing Litter and People’s Imagination

The story of a shared vision to raise awareness and reduce litter through research and creativity.

Have you ever noticed litter in or near the water and wondered if there was something more you could to do raise awareness of the problem while at the same time implementing a solution to tackle the challenge? This curiosity was what brought Chelsea Rochman and Susan Debreceni together in a partnership to tackle a global problem. It was just more than two years ago when Chelsea and Susan were inspired by the famous Mr. Trash Wheel in Baltimore and met up with a shared goal to bring a similar wheel to Toronto. Without a clue about how to do this, they began their journey.

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Chelsea, Susan and Rafaela in Baltimore, Maryland during a visit with Mr. Trash Wheel and his inventors (December 2018).

At the time, Susan was working for Ocean Wise helping lead the Great Canadian Shoreline Cleanup and Chelsea was starting her career as an Assistant Professor at the University of Toronto in the department of Ecology and Evolutionary Biology. Together, they knew that having a Trash Wheel in Toronto would capture the public’s attention and become an incredible centrepiece for an education and outreach program helping increase waste literacy in the local community and beyond.

To get started, they reached out to the inventors of Mr. Trash Wheel in Baltimore as well as PortsToronto, who own and manage several areas of Toronto’s waterfront. Immediately upon reaching out, both groups responded to learn more. Shortly afterwards, Chelsea and Susan were joined by Dr. Rafaela Gutierrez, an expert in social science and waste management. These conversations quickly turned into a feasibility study to see if Toronto was a good location for a Trash Wheel. Quickly, Susan, Chelsea and Rafaela gathered a team of 25 undergraduate and graduate students who all shared the same passion for increasing waste literacy.  At the time, it was looking like the Don River would be the ideal location for such a device, but ultimately through the results of this study and many, many, many meetings and phone calls with a growing list of stakeholders, the team was struck with the realization that a Trash Wheel was not the best waste solution for Toronto at that moment in time.

Instead of calling it quits and throwing in the towel, they continued to brainstorm with PortsToronto about other waste capture options, including a Roomba like swimming vacuum, capture devices at the end of storm drains, litter skimming vessels and Seabins. Soon after, PortsToronto’s Sustainability Committee began an active discussion about Seabins and connected with the Seabin Project to learn more. Then, in the summer of 2019, two bins were installed in the Outer Harbour Marina.

Big and Little Plastics
An assortment of plastics were captured from Seabins in the Outer Harbour Marina.

It was only a matter of days into the initial Seabin trial when the bins were visited by dozens of curious visitors, generated several media interviews and removed 2000+ pieces of plastic from the marina. Everyone was thrilled and as a result we were off to the races and our Trash Wheel at the mouth of the Don River was turning into a plan for more Seabins along the Toronto waterfront.

In the early weeks of October, two additional Seabins were installed in Toronto’s Inner Harbour at Pier 6. On a cold and windy morning a group of local NGOs, the Ontario Minister of the Environment, the local Member of Provincial Parliament, and a Councillor of the Mississaugas of the Credit First Nation were brought together to celebrate the new bins. In front of the local group, the bins were introduced and demonstrated, and preliminary litter data from phase 1 was shared, all while enjoying hot coffee (in reusable mugs) and Beaver Tails (a famous and delicious Canadian pastry!).

One of the new Seabins at Pier 6 in the Toronto Harbour.

This day was incredibly special and meaningful. It was not only a celebration of the new Seabins, it was also a celebration of how far our team had come and where we were headed. Over the last two years, our hard work and perseverance created a local community group –  the U of T Trash Team – a dedicated and passionate team that includes undergraduate and graduate students, postdocs and dedicated staff. The U of T Trash Team’s mission is to increase waste literacy in our community and reduce plastic in our ecosystems.

As a group, the team has developed new waste-literacy school programming, scheduled to begin this year at Grade 5 classrooms across the Greater Toronto Area. The team also runs community outreach programming – including two annual cleanups per year in collaboration with Toronto Region Conservation Authority and Ocean Conservancy. Additionally, the team focuses on solutions-based research – including a pilot project installing lint traps in 100 homes in a small community to divert microfibers from Lake Huron, and working with industry to achieve zero pellet loss to Lake Ontario. And finally, the U of T Trash Team is a proud partner with PortsToronto on the Seabin pilot to “litter”-ally trap trash on its way out to Lake Ontario, preventing it from contaminating our waterways, our fish and our local drinking water.

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Written by Chelsea Rochman; Assistant Professor at University of Toronto, co-founder of the U of T Trash Team, and Scientific Advisor to the Ocean Conservancy & Susan Debreceni; Outreach Manager and co-founder of the U of T Trash Team

Our Time at The Experimental Lakes Area

This summer, three members of the Rochman lab (Chelsea Rochman, Kennedy Bucci, and Hayley McIlwraith) were lucky enough to spend two and a half weeks at the IISD-Experimental Lakes Area to conduct microplastic sampling.

What is the Experimental Lakes Area (ELA)?

If you’ve ever taken an undergraduate-level course in ecology or biodiversity, you’ve probably heard about this distinguished research station. The ELA is a system of 58 lakes set aside for research. It is located in a sparsely populated area of Northwestern Ontario, far from industrial development. Although the ELA was previously government-funded and run by the Department of Fisheries and Oceans, it is now privately owned and run by the International Institute of Sustainable Development (IISD).

In 1974, David Schindler (founding director of the ELA) and his colleagues conducted a simple, yet elegant experiment to better understand how algae can take over an entire lake, creating an algal bloom. They decided to split Lake 226 in half, and add nitrogen and carbon to one half, and nitrogen, carbon, and phosphorous to the other. When the algal blooms only appeared in the half with phosphorous, they knew that phosphorous was a key factor driving algal blooms. As a direct result of this experiment, countries around the world took action to limit the amount of phosphorous entering their waterways. This experiment demonstrates the importance of the ELA as a natural laboratory. Researchers can gather impactful evidence to better understand key issues affecting the natural world and then use this information to inform policy and encourage positive change.

What research were we working on at the ELA?

The goal of this summer’s project was to determine whether the remote lakes at the ELA are contaminated by microplastics. By now, we know that plastic is a globally ubiquitous contaminant: it’s been found everywhere from urban areas, such as the Don Valley River in Toronto, to more remote locations, such as the Mariana Trench and the Arctic. Sampling at the ELA gave us a unique opportunity to evaluate contamination in remote freshwater lakes.

Just how remote is the ELA?

The field station is located at the end of a 30 km gravel road off the Trans-Canada Highway. It consists of a meal hall, 3 dormitory cabins, a chemistry lab, and a fish lab. Due to its remote location, the camp is not connected to Ontario’s main power grid and thus remains completely off the grid: there is no cell service and very limited Wi-Fi (used for research purposes only).


What was daily life like at the ELA?

So, what’s it like to be a visiting student at the ELA? To live and work at this natural laboratory? In summary: it’s pretty sweet.

Hayley McIlwraith
One or two dogs were usually waiting outside the dining hall each day. © Hayley McIlwraith

A typical day went like this: wake up early, get dressed, go to breakfast at 7:30 am, pet a dog (there were usually 1 or 2 waiting outside the dining hall), eat, meet with colleagues/supervisors to go over the plan for the day, travel to the sample site, collect samples, eat a packed lunch (always sandwiches), travel to next site, sample, travel back home, hopefully make it back for dinner (very rare, but there were always leftovers), participate in fun evening activity, pet a dog, sleep. Repeat.

Minoli Dias
At our sampling sites, 20L of surface water was pumped through a series of filters. At some sites, we also took sediment cores (pictured here) from the lake bottom.  © Minoli Dias

Reaching our sampling sites could take 30 min to 2 hours, depending on the lake. To access each lake, we used a combination of driving, boating, canoeing, and portaging. The easiest site to reach was Lake 239, which was accessible by motorboat. The most difficult site to reach was Teggau Lake, where we paddled across Lake 239, portaged, paddled across Roddy Lake, and finally portaged another 1.2km before finally arriving at the site. Even though it was a long journey, we were lucky to have an amazing group of people that made the trip seamless and worthwhile.

By the time we returned to camp, we were always exhausted and hungry. Luckily, the camp chefs had prepared a delicious meal while we were away. And it never disappointed – the food was always plentiful and delicious. Some of our favourite meals included pizza, beach barbecues, and pumpkin pancakes.

After dinner, there was usually a fun activity for us to participate in. This included Wednesday night seminars where we learned about on-going projects at the ELA, sing-along bonfires, a paint night, art shows, and even a triathlon. These events were well-attended by everyone at camp, despite our long workdays.

While our days at the ELA were long and grueling, our stay was impactful. Every minute involved trying or learning something new, chatting with researchers and new friends, or simply enjoying the raw nature around us.

Kennedy Bucci
© Kennedy Bucci

What’s next for our work at the ELA?

Our ultimate goal at the Experimental Lakes Area is to do a whole-ecosystem experiment. In contrast to typical laboratory experiments, this large-scale experiment would provide us with ecologically relevant information about the fate and the effects of microplastics. Similar to the famous algal bloom experiment, this project has the potential to influence global action on plastic pollution.

Written by Kennedy Bucci and Hayley McIlwraith, students and researchers in the Rochman Lab. Their work is in collaboration with multiple institutions, including: University of Toronto, Lakehead University, Queen’s University, Environment and Climate Change Canada, and, of course, IISD-ELA.

Kim Geils 2
© Kim Geils

What Litter is Entering Toronto’s Outer Harbour Marina?

A preliminary look at what Seabins are collecting along Toronto’s waterfront.

This past August, PortsToronto installed two Seabins at Toronto’s Outer Harbour Marina and we visited them to count the litter they captured. This was done to help measure their effectiveness and better understand what litter is reaching our Great Lakes. Resembling underwater garbage cans, Seabins help clean the harbour by pumping water through a catch bag. This action removes, along with other contaminants, plastic litter greater than 2mm in length.

Removing Seabin from harbour.

Although it was our first-time quantifying litter from Seabins, it wasn’t our first time counting and classifying trash. We’ve spent many hours over the past few years searching for plastic in an array of environmental samples. These experiences have taught us a lot, but one of the biggest takeaways is that plastic pollution is ubiquitous. With this in mind, we were prepared to spend the entire day counting; however, when we arrived at the marina, we were pleasantly surprised. Since we’ve both participated in community cleanups before, we expected to find large amounts of litter (as this was the trend for many cleanups in urban areas); however, upon arrival our presumption quickly changed. The water was clear and the docks were tidy… surely the Seabins wouldn’t have much to catch then, right?

Size definitions for ‘big’ and ‘little’ plastics: big plastics were’ bigger than or equal to the size of a nickel’ and little plastics were ‘’between the size of a nickel- and nurdle’ (represented by orange arrow).

Turns out appearances can be deceiving. Half a day later, we’d only finished the easy part: removing plastics larger than a nickel (what we classified as “big plastics”). It would take days to count all the “little plastics” too (those smaller than a nickel but equal to or bigger than a nurdle, small pre-production pellets used in the production of plastic products). Because of this, we decided to subsample and extrapolate the results. After another half day and some quick calculations, the results were in: nearly 2000 pieces of plastic between the two bins. Amazingly, it had all accumulated in less than 24 hours.

Breakdown of how litter was sorted and main results.

Much of this experience was surprising, from finding almost 2000 plastics in a seemingly clean environment to having a passersby ask us whether or not we’d found gold. (The answer, unfortunately, is still no). Overall, it was a rewarding learning experience, and a great chance to share our work with those at the marina. It was also a wonderful opportunity to learn more about how to mitigate plastic pollution – including microplastics. Together with other waste management systems, we feel Seabins are an effective form of technology to assist in protecting our bodies of water and are excited to see more innovative technology in the future.

Preliminary results indicated a high amount of plastic fragments.

Written by Annissa Ho and Lara Werbowski, two HBSc students at U of T who are members of the Rochman Lab and U of T Trash Team.