A recent study reveals Toronto’s Don River is a significant source of pollution, flushing an estimated 500 billion microplastic particles—totaling 36,000 kilograms—into Lake Ontario each year. This mass, equivalent to about 18 cars, shocked co-author Chelsea Rochman, who noted the levels are comparable to regions with poor waste management. These microplastics, originating from sources like construction foam and car tires, far exceed the amount of larger plastic debris, such as wet wipes and bags, also found in the river.A primary contributor to the problem is Toronto’s aging combined sewer system. During heavy rain, this system is overwhelmed and overflows, discharging untreated sewage and improperly flushed items directly into the watershed. To address this, the city has initiated a $3-billion infrastructure program to upgrade the system and mitigate these overflows.While microplastics are known to negatively impact wildlife, the study provided a hopeful outlook. Researchers observed that plastic levels in the river remained stable before and after storm events. This finding suggests that if the primary pollution sources are effectively “turned off” through infrastructure improvements and better waste control, the Don River may have the capacity to naturally clean itself over time. However, key questions remain: Why did the city’s infrastructure fail so badly, and what does this failure say about our real priorities? Who should help pay for the $3-billion cleanup and sewer fix?