A smell of rotten eggs has plagued visitors to an Edmonton-area park for years, but there might be more to worry about than just an annoying odour.
University of Alberta neuroscience professor David Bennett decided to test the air at Gold Bar Park for hydrogen sulphide after noticing an off-putting smell while cross-country skiing with his family.
The park is close to a waste treatment plant.
What he found was pretty concerning — the air was showing levels of 25 parts per billion (ppb) of the gas, significantly higher than the government's objective of 10 ppb.
Gas could be dangerous with long exposure
Gold Bar Park is a popular destination for cross-country skiing in winter, and picnics in the summer.
"There are kids or people down there for many years skiing,” Bennett told Global News. “If they’re [breathing in] 25 ppb, and you multiply that by their 40 times higher breathing rate, you’re getting to 1,000 ppb… which is where you have to start worrying about acute health effects.”
Hydrogen sulphide can be deadly, especially in enclosed and confined spaces, but there can still be serious effects for those exposed to the gas in open air.
"There are kids or people down there for many years skiing... which is where you have to start worrying about acute health effects."
According to the Canadian Union of Public Employees, low-level exposure to the gas can cause "painful eye, nose and throat irritation, headaches, fatigue, irritability, insomnia, gastrointestinal disturbance, loss of appetite [and] dizziness. Prolonged exposure may cause bronchitis and pneumonia."
The 10 ppb standard itself may be due for a review — Alberta Ambient Air Quality Objectives and Guidelines show that the safe levels of hydrogen sulphide were both established and last reviewed in 1975. The government also bases its guidelines on the strength of the substance's odour, not the effect the gas has on health, unlike the World Health Organization's recommendations.
Bennett submitted his findings to Alberta Health, who confirmed to CBC News that the agency would be conducting a review.
“We badly need an ambient air guideline based on health, rather than odour,” Bennett wrote in the letter, according to the Edmonton Examiner.
Alberta Health to contact waste treatment plant
Alberta Health Minister Sarah Hoffman's office also confirmed that it would be asking the nearby plant to work on lowering its emissions.
In the meantime, park visitors should keep their nose to the air — a rotten smell might be a good sign to steer clear.
“It’s fine to walk by it, but to be in that area for a prolonged time, I would just say is not a good idea,” Bennett said in an interview with Metro News.
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