Hamilton ‘black soot’ not expected to pose long-term risk, public health says

Hamilton Public Health (HPH) officials say a black particulate that fell across parts of the city last month is not expected to pose a long-term health risk.

In a news release on Thursday, the agency said its assessment of the early July event found exposure levels were likely low, based on air quality data, environmental samples and the limited duration of the incident.

Some residents may have experienced mild symptoms, including itchy eyes, coughing or a sore throat. However, a review of local hospital data found no increase in emergency department visits for more severe symptoms.

“The health and safety of residents remains Hamilton Public Health’s top priority,” said Dr. Elizabeth Richardson, the city’s medical officer of health in a news release from HPH.

“The emissions in early July were a short-term worsening of those Hamiltonians experience on a daily basis. This short-term event isn’t expected to have long-term health risks on its own. However, the event contributes to the existing burden on the airshed, particularly the disproportionate impacts experienced in the north end of Hamilton.”

The findings come amid longstanding concerns about black soot in neighbourhoods near Hamilton’s industrial area.

McMaster University researchers recently studied the mysterious black grime that residents reported finding on homes and yards for years.

Researchers said coal combustion was a likely source of the dust, but found its composition was complex and pointed to multiple sources.

Ontario NDP Leader Marit Stiles has also raised concerns about the soot, saying in a video posted to social media that Hamilton residents filed 475 complaints with the province’s environment ministry over a nine-day period.

She said parents have been wiping the soot from shoes, slides and parks, questioning, “What is in the air we are breathing?”

The NDP leader directed residents to CleanupTheSoot.ca , which includes information about the issue and a petition calling for action.

The latest public health assessment focuses specifically on the black particulate reported in early July.

Ontario’s Ministry of the Environment, Conservation and Parks determined emissions from Birla Carbon on Parkdale Avenue North were the primary source of that event.

Environmental samples collected by the ministry mainly contained carbon, along with small amounts o2f sulphur and very small amounts of mineral particles.