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News release
July 14, 2023

Climate change is a health threat, Ontario’s doctors warn

TORONTO, July 12, 2023 — The World Health Organization has identified climate change as this century’s single biggest health threat.

Smoke from wildfires in northern Ontario are making it difficult to breathe for millions of people in Canada and the United States. This month, the world has seen some its hottest days on record. And ticks are now able to survive Ontario winters, leading to an increase in Lyme disease.

Climate change has also worsened mental health, said physicians who spoke at an Ontario Medical Association media briefing.

“There are countless studies that show that nature alleviates anxiety, decreases depression and even accelerates recovery from surgery,” said Dr. Gili Adler Nevo, chair of the OMA’s Green is Health medical interest group. “This is the same nature that climate change is depleting.”

Dr. Adler Nevo, who is a psychiatrist at Toronto’s Michael Garron Hospital, works primarily with youth who have been diagnosed with anxiety disorders. Dr. Adler Nevo said that her patients, who grew up in a world in which “climate change is a fact,” constantly worry about the planet’s future.

“The climate is no longer predictable,” she said. “We have hailstorms in the middle of summer, we have very warm winters and people cannot skate any longer in their backyards the way they've been doing for decades. That uncertainty is very unhealthy psychologically, more than extreme cold or extreme heat. The unpredictability is a problem.”

Panellists also discussed how climate change is adding stress to emergency departments across the province.

“Typically, we have a rise in emergency department visits,” said OMA president Dr. Andrew Park, who moderated the briefing. Dr. Park, who is an emergency room physician in London, explained that when the air quality is lower, there is an increased particulate matter in the air. When these small particulates reach body parts such as eyes and lungs, they can cause an immune reaction.

A 2021 heat wave in British Columbia resulted in a large rise in common illnesses and health complications, such as heat stroke, dehydration, chronic soreness, dehydration and kidney failure, said Dr. Park. During the heat wave, many patients went to emergency departments for help.

These heat-related issues are a particular concern for low-income populations, said Dr. Park, many of whom lack access to air conditioning and cooling centres. Black, Indigenous and other marginalized communities are also most often hit hardest by the impacts of climate change.

“Socioeconomic factors, medical factors, lack of housing, lack of income, lack of education …  all those things determine our health,” said Dr. Park. “The vulnerable continue to be pushed down as opposed to being propped up. Climate change creates a furthering of inequity in our population that makes it harder for people to access the basic institutions, such as health care.”

While the health-care system itself also contributes to climate change, panellists said that there are steps physicians can take to develop a culture of sustainability.

Canada’s health-care system creates nearly five per cent of the country’s greenhouse gas emissions, which is more than the country’s aviation industry. Ontario’s Anesthesiologists, a section of the OMA, developed a position paper with recommendations of how to reduce this impact.

Ontario’s Anesthesiologists also started an environmental sustainability working group to focus on the reduction of anesthetic gases contributing to greenhouse gas emissions and the reduction of single-use supplies in operating rooms.

The anesthetic drug desflurane has a large carbon footprint and is more expensive than some other options, explained Dr. David Ohrling, chief of the Department of Anesthesiology at Collingwood General and Marine Hospital. A growing number of Ontario hospitals have stopped using desflurane.

Another problem is hospital operating rooms relying on single-use medical devices and supplies. Dr. Ohrling said that operating rooms generate between 20 to 33 per cent of hospitals’ total .

“If you're having major surgery, the surgical instruments that are being used for those operations are all reused,” said Dr. Ohrling, was the lead author of the Ontario Anesthesiologist’s paper. “We have experts in our hospitals who do a medical device reprocessing and sterilization. They have the tools and the equipment to properly and safely reprocess equipment.”

The working group plans to collaborate with the Canadian Health Coalition, a public advocacy organization, and hospital procurement officers to discuss how hospitals can encourage suppliers to design their products to be reusable.

“We need hospitals measuring their greenhouse gas emissions, having targets to try and reduce them, and have sustainability goals embedded in their strategic plans and their policies,” Dr. Ohrling said.

Dr. Ohrling said other initiatives could include embedding sustainability in medical school residency programs so that future physicians could gain experience combatting climate change.

“Doctors are in the business of improving people's health. We shouldn't be worsening people's health by worsening the climate crisis,” Dr. Ohrling said.

About the OMA

The Ontario Medical Association represents Ontario’s 43,000-plus physicians, medical students and retired physicians, advocating for and supporting doctors while strengthening the leadership role of doctors in caring for patients. Our vision is to be the trusted voice in transforming Ontario’s health-care system.

For more information, please contact:

Leslie Shepherd
Director, Earned and Social Media
Ontario Medical Association