A group of scientists in Hamilton has uncovered insights into the issue of soot deposition in neighborhoods surrounding the city’s industrial zone. Residents have long complained about a dirty, dark residue covering their properties, with a recent spike in fallout reported in early July.
Sarah Styler, an associate professor specializing in environmental chemistry at McMaster University, and Grace Yao, a PhD candidate under Styler’s supervision, are part of a research project titled “What’s the Grime?” aimed at addressing the origins of the soot. Through sample collection conducted with volunteers across the city in 2024 and 2025, the researchers identified hazardous chemicals in the soot consistent with coal combustion. Additionally, elevated levels of dust and polycyclic aromatic hydrocarbons (PAHs) were found near the industrial region in northeast Hamilton.
Collaborating with Environment Hamilton, Styler initiated the study, funded by a $15,000 grant from the university in 2024. Both Styler and Yao, residing in east Hamilton and Corktown respectively, have personally encountered the soot issue. According to Styler, historical records dating back to the 1950s have documented instances of the soot problem.
The investigation involved the distribution of sampling kits to 50 volunteers’ homes throughout the city, with scientists collecting and analyzing samples at four-month intervals. Styler highlighted that more dust and toxic compounds were observed closer to the industrial sector, emphasizing the presence of harmful substances in the vicinity.
The study’s findings, particularly concerning the prevalence of PAHs, were deemed unsurprising by Styler, considering the proximity of affected communities to industrial facilities emitting the soot. Despite community frustrations over the lack of official information, the Ministry of the Environment, Conservation and Parks has pledged to conduct further testing to identify potential sources of the soot.
Styler’s team plans to present their research outcomes at a community gathering on August 20, with intentions to expand the study to include 200 volunteers and explore additional compounds present in the soot. They are also interested in investigating effective cleaning methods for the soot residue.