Study tracks ‘rotten egg’ smell in lower city
Research team seeking volunteers to host air monitors that record levels of hydrogen sulphide
In an infamously fragrant industrial city, that “rotten egg” smell might still be Hamilton’s most common fetid foe.
It is often associated with hydrogen sulphide, a gaseous pollutant that can waft out of sewers, leak out of landfills or spew as industrial pollution from processes like steelmaking.
Now, a University of Toronto research team wants to track the most stinky hot spots for the culprit behind the “classic eggy, sulphurous smell” — and if possible, measure how much of the gas migrates into nearby homes, said professor Matthew Adams, an urban airquality expert who routinely conducts research in Hamilton.
So if you’re interested in validating your own eye-watering observations with scientific sniff-test data, Adams and his team are looking for lower-city volunteers to host small, indoor air samplers.
Adams said he decided to embark on the indoor-outdoor smell test following a two-year air-quality monitoring study in neighbourhoods across the city that yielded plenty of feedback about odour.
“Anecdotally, we do hear a lot of complaints about odours … but it can be a really hard thing to quantify,” Adams said in an interview.
Luckily, hydrogen sulphide and its recognizable stench are easily trackable with passive air monitors.
The nose-wrinkling chemical emissions are also publicly reported by major industries via the National Pollutant Release Inventory. (In Hamilton, that’s primarily steelmakers and users or manufacturers of carbon black.)
“This is a specific compound in the air that we can actually measure,” Adams said. “We’re also hoping it will help us determine the likelihood of other (air) pollutants making their way indoors.”
So far, Adams said he has eight households signed up to host a small, “passive” air monitor that simply sits indoors and absorbs any passing pollutants for a week or two at a time. An outdoor monitor is also attached nearby and above head height on poles or buildings.
More volunteers in the study are welcome, he said, because the team aims to measure hydrogen sulphide concentrations in spring, summer and fall. (The study area is roughly within 1.5 kilometres of the industrial core.)
The low-tech learning opportunity will likely be appreciated by residents living near the industrial bayfront, predicted Kerry Le Clair, a neighbourhood pollution advocate and current climate action co-ordinator for Ward 3 Coun. Nrinder Nann.
Le Clair, who helped organize a “worst smell” survey in the ward in 2022, said residents are worried about “mystery odours” in their neighbourhoods, both because of the nuisance factor but also the unknown health impacts.
She said having reliable data helps back up anecdotal complaints and gives advocates more ammunition to push for action from environmental authorities. “The more specific information we have, the better,” said Le Clair.
Adams said hydrogen sulphide gas can be an eye-watering irritant and cause low-level respiratory distress, but it is primarily a “nuisance” odour in the concentrations he expects to find in neighbourhood air quality.
Still, the stress of dealing with constant strong odour can also be a health problem, he noted.
Stoney Creek residents learned that the hard way last year when leachate from a private landfill spurred months of complaints from visitors and homeowners who reported the intense odour caused migraines, coughing and nausea.
If you’re interested in participating in the study, email md.adams@utoronto.ca.