The City of Toronto's top public health official is recommending the city lower its speed limits by 10 to 20 kilometres-per-hour in an attempt to protect pedestrians and cyclists.

In a report released this week, Dr. David McKeown, Toronto's medical officer of health, proposes a 30 kilometre-per-hour speed limit on residential streets and a citywide speed limit of 40 km/h on all other streets, unless otherwise posted.

Currently, most Toronto streets have speed limits of 40 km/h or 50 km/h, although some major routes are a 60 km/h speed zone.

In a report dubbed Road to Health: Improving Walking and Cycling in Toronto, McKeown argues lower speed limits would reduce the severity of injuries in collisions.

According to the report, more than 1,000 cyclists and more than 2,000 pedestrians report being injured in collisions with motor vehicles in an average year in Toronto.

Due to under-reporting, the actual number of collisions is likely much higher, McKeown wrote in his report.

Elderly pedestrians are most likely to be killed in collisions with vehicles, while children and residents of low-income neighbourhoods may also be particularly at risk of injury when walking and cycling, the report found.

In Toronto, collisions most frequently occur at intersections and on major arterial roads, McKeown wrote.

In addition to saving lives, preventing collisions would cut taxpayers' costs.

"Each time a pedestrian or cyclist is involved in a collision with a motor vehicle, costs are incurred for not only the individual (lost productivity), but for the healthcare system (ambulance, emergency department visit, hospital stay and medical care), and Toronto services (police, fire and traffic delays)," McKeown wrote in the report.

Depending upon the severity of injuries, the costs can range from $2,445 per person for a minor injury to $33,680 for a fatality, with costs totaling $53 million for pedestrian collisions and $9 million for cyclist collisions, the report found.

McKeown's report will be on city council's agenda next month.

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