Wildfire smoke in Manitoba may contain heightened toxicity levels, necessitating further investigation into the pollutants being discharged into the atmosphere, as per experts. The fires could be releasing long-stored pollution from the province’s soil, including harmful substances accumulated over centuries of exploitation in the north, stated Colin McCarter, the Canada Research Chair of Climate and Environmental Change.
Approximately one-third of the province is covered by peatlands, crucial carbon repositories that also serve as natural fire barriers. However, with climate change increasingly jeopardizing these wetlands, there is a potential risk of a “pollution time bomb” being triggered, McCarter warned. Peatlands are significant landscape storages of toxic metals, ranging from common elements like copper to more hazardous ones such as lead, arsenic, and mercury, all linked to adverse human health effects.
McCarter highlighted that peatlands have the ability to sequester a considerable amount of these toxic metals compared to other ecosystems. Areas rich in peatlands in Canada are often in proximity to regions with a history of industrial activities and resource extraction, exemplified by locations like Flin Flon. The recent massive wildfire in the province, which led to the evacuation of a city around 760 kilometers northwest of Winnipeg, underscores the pressing concerns surrounding the situation.
Moreover, the closure of the last mine in Flin Flon in 2022 and the shutdown of its long-operating copper-zinc smelter in 2010 have raised environmental alarms. The smelter was once a major emitter of sulfur dioxide, with subsequent studies revealing elevated levels of mercury and other metals in various environmental samples around the region. The smelter was identified as the largest single source of atmospheric mercury emissions in Canada during its operational phase.
McCarter emphasized that various sites across Canada, including Flin Flon and Thompson, exhibit landscape-level pollution due to historical industrial contamination in fire-prone boreal ecosystems. While the potential toxicity of released pollutants depends on factors like fire temperature and peatland type, the link between peatland contents and associated risks remains a focal point of ongoing research efforts.
Michael Schindler, a mineralogist and professor at the University of Manitoba, highlighted the issue of contaminants, such as lead, zinc, mercury, and selenium, mixing with wildfire smoke and posing health risks. The finer particles in smoke act as carriers for these contaminants, facilitating their inhalation into the lungs and exacerbating health impacts. Schindler expressed concerns about the long-range transport of wildfire smoke, which can carry toxic metals across vast distances, potentially compounding health issues when mixed with urban pollutants.
As the community of Flin Flon grapples with the aftermath of the recent wildfire, residents like Dave Price underscore the importance of monitoring the source and composition of smoke to safeguard public health. Efforts are underway to expand air quality monitoring in the region, with a focus on maintaining clean air amid growing concerns over the impacts of wildfire smoke on human health.