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.

Reconnecting with our urban shorelines

How we protect our watersheds, one neighbourhood at a time

On a sunny September weekend, groups of community volunteers led by the U of T Trash Team gathered at ten different locations in and around Toronto for the Urban Litter Challenge. This annual cleanup is timed to coincide with the International Coastal Cleanup, and while you might not think of ocean coastlines when you think of Toronto, all drains here lead to a river and/or the Laurentian Great Lakes which eventually lead to the Atlantic Ocean through the St. Lawrence River. Every location around the world is on a watershed, leading to a river, lake and/or ocean – and our Urban Litter Challenge is aimed at connecting the dots from where you live (even if it’s inland) to an aquatic ecosystem. Inland cleanups like these are not only really fun, but can help protect aquatic resources and biodiversity.

Take a look back at our cleanup with our vlog created by U of T Trash Team volunteer and Site Lead, Devajyoti Chakraborty.

By spreading out across different urban locations, our team was able to explore new neighbourhoods and help connect diverse communities to their local watershed. This led to unique conversations about shared experiences at each location. Here are just a few!

  • To remove, or not to remove? At Cedarvale Ravine, volunteers had a lively discussion about whether or not to remove litter embedded in the ground. While it didn’t belong there in the first place, there was now potential to disrupt the natural environment or any newly created habitat for organisms by attempting to remove it.
  • Nurdles all over! At Ward’s Island, a popular cleanup spot, plastic nurdles took the spotlight. These tiny plastic pre-production pellets are a form of microplastic and can be found in this form before they are melted down and moulded into plastic products. Unfortunately, at times, these accidentally spill into the environment from nearby plastic factories and wind up on our shorelines.
  • Ever heard of cellulose acetate? A common cleanup item created new awareness for volunteers at Riverdale Park East. Cigarette butts dominate litter tallies at cleanups, however it’s not common knowledge that paper like filters contain a type of plastic known as cellulose acetate. A volunteer at this cleanup who smoked was surprised to see just how many butts there were, and that they were made from plastic. She vowed to help keep these out of the environment and tell her friends to do the same.
  • What goes in which bin? Site leads at Ashbridge’s Bay Park East helped explore the difference between what goes into the trash and recycling by providing a mini tutorial for their volunteers before the cleanup, an important step to ensuring litter we find can be effectively managed!

Volunteers at Ward’s Island sift through the tiny trash for items like plastic nurdles.

Teams were also able to make some great new community connections. Our Ashbridge’s Bay cleanup welcomed a team of local Girl Guides passionate about reducing waste, and over in the west end at Sunnyside Beach, the team met up to celebrate with Roncy Reduces who had hosted a neighbouring cleanup! Over at the Toronto Music Gardens, rugby players from the U of T varsity team gathered to show their team spirit. Our volunteers also ventured out of the city to add a new cleanup in Vaughan at Maple Lion’s Park, and it was a delight meet up with community members in this new location.

It’s incredible what you can do when you work together. Across ten locations, 154 volunteers removed 16,132 different items of litter. The top items removed include cigarette butts, small plastic pieces, and food wrappers! In response to COVID-19, we also kept a tally of personal protective equipment (PPE), and our Rennie Park location found the most with 78 different items of PPE. This is particularly notable as Rennie Park volunteers also found quite a bit in 2020!

Summary of cleanup results across all ten locations of the 2021 Urban Litter Challenge

Top 10 litter items found across all ten locations of the 2021 Urban Litter Challenge

These results also included some pretty unique finds, like a euro at Trinity Bellwoods, a lost (and returned) wallet at Coronation Park, and a flatscreen TV at Riverdale Park (note: we also found a tv last year at Barbara Hall Park!).

A look at some of the unusual finds during the 20201 Urban Litter Challenge.

Community cleanups are one of the best and most accessible ways to make a positive difference in just a few hours. They are also one of our teams’ favourite experiences and ways to increase waste literacy. You can head out on your own or grab a team of friends and family to help. As we highlight through Urban Litter Challenge, removing litter from any public area will help protect our watersheds and prevent plastic and other litter from reaching our aquatic ecosystems, which for us means our beloved Great Lakes. 

Blog written by Susan Debreceni, Program Lead of Volunteer Engagement and Community Programs for the U of T Trash Team.

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.

Waste Literacy Education in a Virtual World

How we adapted classroom programs for virtual learning

Aligned with our mission at the U of T Trash Team, one of our goals is to engage young minds about waste literacy. Teaching plastic pollution is a meaningful way to help future generations learn to prevent waste and choose more sustainable lifestyles. Participation in environmental education activities can improve children’s environmental knowledge and attitudes[1]. It may also help shift behaviour. With all of this in mind, our team designed a series of lessons for Grade 5 students to improve scientific and waste literacy and to foster a sense of curiosity about the natural world and human impacts on the planet.

Our lessons were co-created among our team of young volunteers, many actively researching plastics in aquatic environments. In total, we created four lessons: 1) plastic cycle, 2) watersheds and their relationship to litter, 3) impacts of plastic on ecosystems and 4) solutions to plastic pollution. These lessons were created in 2019 and piloted in the classroom in early 2020.
They were initially created to be delivered in person with all sorts of fun hands-on activities. Little did we know that the COVID-19 pandemic would change our plans.

From the classroom to the computer

As many groups around the world also experienced, we had to quickly adapt to the virtual world. It wasn’t easy at first and there were many new technological skills to learn in this new online learning environment. We also had to reconsider our activities – because elementary students could not share materials. This meant experiments, games and activities couldn’t be done in groups and had to be provided for them to play independently. A lot of planning and effort was put into redesigning the lessons to make sure we could keep the same learning objectives while providing interactive activities that would still be just as fun remotely.  For example, in one activity we explore how plastic travels in a watershed with a game called Float, Sink or Suspend. Students create a hypothesis about how different types of plastic behave in the water column and test this out by dropping them into a container of water and observing the results. To adapt to online, we had students share their hypotheses through fun movements: a backstroke for float, an anchor for sink, and wiggling their arms like a jellyfish for suspend, and created a video to show what happens to each item. Not only did this activity allow an opportunity for play, but it also provided time to get up and stretch.  

Teaching in a virtual world

Another important piece of this process was adapting to online teaching. In our program, students are taught by our incredible Waste Literacy Instructors – a team of undergraduate students, graduate students and early-career scientists who volunteer their time to mentor Grade 5 students. These volunteers embraced the task, and were excited and ready to deliver high-quality peer-to-peer lessons with high energy in a virtual classroom. To achieve this, we trained our instructors for each lesson with a focus on four things: content, pedagogy, engaging a class online, and the tech. This provided a unique opportunity to learn new communication skills. Our instructors did great, and had a lot of fun while doing so. Su’aad Juman-Yassin and Anusha Srinivasan both echoed those sentiments:

“I thought it would be a great opportunity to work on my science communication skills. I also find it very fulfilling to be able to understand a concept and facilitate that understanding for someone else.” (Anusha)

“It is a super fun way to connect with lots of amazing students and teachers and I have definitely learned an interesting fact or two from the lesson plans myself!”[…] “The final lesson in our classroom series is all about finding solutions to plastic pollution. Students are tasked with coming up with a creative way to combat plastic pollutants and the amazing ideas they come up with, from a Jet ski contest … to a giant mechanical fish that eats plastic …, are always so exciting to hear about!” (Su’aad)

Landing in a virtual classroom

Teachers welcomed us into their virtual classrooms, and provided our volunteers and their students with a great experience. They went above and beyond by providing guidance and feedback to improve our lessons and keep students engaged. Although we would have loved to have been together in person, an online classroom still provided the space we needed to have positive impact.

Looking back, there was a lot to be gained from this virtual school year. As a result, we are confident and prepared for whatever scenario comes this fall. The truth is, we can’t wait to be back in the classroom again, whether in-person or remote! With the support of the teachers, the talent of our instructors and the engagement of the students, our team was able to deliver 31 lessons across the Greater Toronto Area during the 2020/2021 school year, inspiring kids and teachers to continue the discussion about plastic pollution despite a global pandemic.

Blog written by Rafaela Gutierrez, Program Lead of Social Science and Educational Programs for the U of T Trash Team and Susan Debreceni, Program Lead of Volunteer Engagement and Community Programs. For more details and to book a classroom visit, please email Rafaela.

[1] Hartley, B.L; Pahl, S., Holland, M.; I. Alampei, J.M. Veiga, R.C. Thompson. Turning the tide on trash: empowering European educators and school students to tackle marine litter. Marine Policy, 96 (2018), pp. 227-234, 10.1016/j.marpol.2018.02.002

Liefländer, A. K., G. Fröhlich, F. X. Bogner, and P. W. Schultz. 2013. “Promoting Connectedness with Nature through Environmental Education.” Environmental Education Research 19 (3): 370–384. doi:10.1080/13504622.2012.697545.

Owens, K.A. Using experiential marine debris education to make an impact: collecting debris, informing policy makers, and influencing students. Marine Pollution Bulletin, 127 (2018), pp. 804-810, 10.1016/j.marpolbul.2017.10.004

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 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.

Coming Together While Staying Apart: The 2020 Urban Litter Challenge

Our socially distanced approach to neighbourhood cleanups.

Cleanups are one of the U of T Trash Team’s favourite ways of connecting with the community AND fighting plastic pollution. Months of planning, research, and outreach culminate into an energizing day of meeting Toronto’s enthusiastic volunteers while protecting our beautiful watersheds.  We live for snagging that 10,000th cigarette butt, removing a nefarious water bottle from the brink of floating in a river, or finally putting a coffee cup in its rightful place (hint: not the recycling bin!).

Last year we hosted our inaugural Urban Litter Challenge (ULC). Why an “Urban” litter challenge? Well, everything upstream connects to Lake Ontario via storm drains, rivers, streams, and creeks in what’s called a watershed. Keeping our lake clean means keeping our inland neighbourhoods and urban centres clean! Our first event was an incredible celebration and a day we’ll always remember, so you can imagine our initial disappointment when we realized that for this year’s International Coastal Cleanup, we wouldn’t be able to clean with our full volunteer team together in one location.

But that didn’t mean we couldn’t have volunteers at all – or a big impact.

Struck by COVID-19 restrictions, we rebounded fast. Coupled with new safety measures, our team revamped the event as a socially distanced cleanup extravaganza. One large cleanup near campus became eleven smaller cleanups across the Greater Toronto Area (GTA) as our site leaders took the trash battle straight to their own neighbourhoods.

What did we find?

By spreading out, we were able to cover over 19 km and reach multiple watersheds with double the number of volunteers (from 80 volunteers to 173)! That also meant more than double the trash was collected (51 kg, 25,595 litter items). We found litter of all types too – 13,000 cigarette butts across all parks, a lone rubber duck at Trinity Bellwoods, a TV at Barbara Hall Park, and even a barbecue at Summerlea! At Christie Pits, Jessica Pellerin (Media Relations and Public Affairs Specialist with PortsToronto) and her partner were shocked to find high numbers of cigarette butts within two hours of cleaning litter.

Small-scale litter was abundant too and at the end of the day our 11 locations cleaned up a total of 4,375 small plastic pieces (plastic less than 2.5cm). Jessica shared that it was an eye-opening experience to see how easily the microplastics, and items like cigarette butts, could be carried into storm drains throughout the watershed.

But if you ask any Trash Team volunteer what their best find of the day was, they’ll tell you the same thing: Community.

Trash Team volunteers were able to lead cleanups in their local parks and share their passion for healthy watersheds with their neighbours. After a challenging year of cancelled travelled plans, working from home, and extensive virtual interactions, local parks have become something of a haven for communities. In a June 2020 survey from Park People, almost three-quarters (70%) of Canadians said their appreciation for parks and green spaces increased during COVID-19.

Volunteers at Rennie Park certainly felt that way, sharing that they felt a newfound sense of importance and responsibility to take care of their park because it’s where their kids play and their families come together. Our leads certainly noticed more multi-generational families and groups of friends this year, helping to clean the parks they’d relied on all summer! Indeed, our Christie Pits’ leaders noted a multitude of small events in the park, ranging from picnics, to dog-walking groups, ballroom dance classes and religious gatherings. It was clear that being stewards of our green spaces is important for both preventing litter from entering our waterbodies and also maintaining precious community space.

This ULC was an important way to recognize the increased impact we’ve been having on our green spaces, too. A couple at Coronation Park mentioned they usually bike through the park, and don’t give too much thought to the masks, gloves, cigarette butts, and microplastics lining the sidewalks and picnic areas. Joining our cleanup helped them slow down and recognize how abundant pollution is. Chris Sawicki (Vice President of Infrastructure, Planning, and Environment with PortsToronto) echoed those sentiments.

“My wife Annemarie and I, and our dog Odie, helped to clean up Rennie park in Toronto’s west end. At first glance, the park seemed quite clean; however, after a couple of hours of work we accumulated a large amount of litter from cigarette butts to discarded face masks largely in and around the parking lot. What a great way to enjoy a beautiful day and do our small part for the environment”.

Chris Sawicki, Vice President of Infrastructure, Planning, and Environment with PortsToronto

This year’s ULC was also a great way to see familiar faces again. Local MP Julie Dabrusin swung by to clean Monarch Park with her Trash Team t-shirt, and TV’s eco-adventurers The Water Brothers (Alex and Tyler Mifflin) came out to support two of our sites! Mike David (Project Manager with PortsToronto) joined us too as a co-lead, and said he enjoyed the opportunity to help clean his local park while raising awareness about litter.

The pivot from one large cleanup to many small cleanups definitely had perks. We were able to better connect with our participants. At Trinity Bellwoods, we met one volunteer interested in learning more about policies around plastic, while another had come to connect with like-minded individuals for a start-up she was creating around sustainable products. Christie Pits’ youngest cleaner Anya was thrilled to be collecting data that would contribute to a national database of litter, and even declared she is inspired to become a scientist when she grows up!

Overall, it was a wonderful day. Cleaning along the likes of Greta Thunberg, the Royal Family, and many others across the world during International Coastal Cleanup Month was inspiring and fulfilling. We’re excited to see everyone at our next cleanup, as we continue to shift perceptions on the abundance of trash in the environment and help develop a responsibility to protect the watersheds of our only home – Earth.

Interested in hosting your own socially distanced neighbourhood cleanup? List your event with the Great Canadian Shoreline Cleanup, anywhere in Canada, all types of shorelines (even watersheds).

Blog written by Natasha Djuric, a proud 4th year Ecology & Evolutionary Biology undergraduate and U of T Trash Team volunteer.

This cleanup was undertaken with the financial support of Environment and Climate Change Canada, PortsToronto, National Geographic Society and Ocean Conservancy.