A group of researchers in Hamilton has uncovered insights into the issue of soot accumulation in neighborhoods near the city’s industrial hub. Residents have long voiced concerns about a dark, sooty residue coating their properties, with a recent surge in complaints in early July described as the most severe in recent memory.
Sarah Styler, an environmental chemistry associate professor at McMaster University, along with Grace Yao, a PhD candidate in Styler’s lab, are part of a research initiative called “What’s the Grime?” aimed at addressing this issue. Through collaborative efforts with volunteers gathering samples across the city in 2024 and 2025, the team discovered that the soot contains harmful chemicals associated with coal burning. Moreover, higher levels of dust and polycyclic aromatic hydrocarbons (PAHs) were detected near the industrial zone in northeast Hamilton.
Styler collaborated with Environment Hamilton on this study, supported by a $15,000 grant awarded by the university in 2024. Both Styler and Yao, residing in east Hamilton and Corktown respectively, have firsthand experience with the soot issue, emphasizing its longstanding presence in the community. The team’s research involved collecting soot samples from 50 volunteers’ homes across the city at regular intervals for analysis.
According to Styler, the closer proximity to the industrial sector corresponds to increased dust deposition and elevated levels of toxic compounds. The researchers noted that PAH concentrations were higher during winter compared to summer, indicating seasonal variations. While the study focused on 13 different PAHs, Styler highlighted the possibility of other toxic components in the soot beyond those compounds.
Styler emphasized the need for further monitoring and analytical capabilities to pinpoint the industrial sources responsible for the PAHs. The findings, although seemingly unsurprising to residents directly impacted by the fallout, underscore the industrial origin of the soot. Despite community frustration over the lack of official information, ongoing testing by the Ministry of the Environment, Conservation, and Parks aims to identify the source of the soot.
The research team plans to share their results at a community meeting on August 20 and intends to expand the study to include 200 volunteers for a more comprehensive analysis of the grime. Additionally, they aim to explore effective cleaning methods for the soot residue.