A group of scientists in Hamilton has shed light on the issue of soot deposition in neighborhoods adjacent to the city’s industrial zone. Residents have long voiced concerns about a dirty, black residue coating their properties, with a recent surge in complaints during early July highlighting the severity of the problem.
Sarah Styler, an environmental chemistry associate professor at McMaster University, and Grace Yao, a PhD candidate under Styler’s mentorship, are part of the research team behind the “What’s the Grime?” study, aimed at unraveling the mystery of the soot’s composition. Through collaborative efforts with volunteers who gathered samples across Hamilton in 2024 and 2025, the researchers identified toxic substances consistent with coal combustion in the soot. Moreover, elevated levels of dust and polycyclic aromatic hydrocarbons (PAHs) were detected in the vicinity of the industrial sector in northeast Hamilton.
Partnering with Environment Hamilton, Styler conducted the study with a $15,000 grant awarded by the university in 2024. Styler, residing in east Hamilton, and Yao, based in Corktown, have personally encountered the soot issue. The study, involving the collection of soot samples from 50 volunteer households at regular intervals for analysis, revealed a higher deposition of dust closer to the industrial area, along with an increased presence of toxic compounds.
Styler emphasized that their research, which focused on 13 different PAHs, unveiled only a fraction of potentially harmful substances present in the soot. Despite resource constraints limiting the scope of the study, Yao highlighted the significant role of coal combustion in generating the identified PAHs. While the team refrained from pinpointing the specific industrial sources of the PAHs, Styler suggested that enhanced monitoring and analytical capabilities could facilitate such determinations.
According to Styler, the study’s outcomes likely confirm the suspicions of residents residing in the most affected neighborhoods, attributing the soot to industrial emissions from facilities like coke plants. However, community members have expressed frustration over the perceived lack of information from official channels. The Ministry of the Environment, Conservation and Parks has been conducting tests to identify the source of the soot, with previous assessments indicating road dust as a predominant component in the particulate matter.
Styler emphasized that their findings contradict the notion that road dust is the primary source of the soot, supporting community claims that industrial activities are the main contributors. The research team plans to share their results at a community meeting on August 20, with ongoing efforts to expand the study to include more volunteers and analyze additional compounds present in the soot. Additionally, they aim to explore effective cleaning methods for the soot-laden areas.
