Health Canada has announced the release of proposed Residential Indoor Air Quality Guidelines (RIAQG) for Benzene, pursuant to subsection 55(3) of the Canadian Environmental Protection Act, 1999. The proposed guidelines are open for public consultation from September 30, 2023, to November 29, 2023.
(*) Benzene Sources: Benzene is a volatile organic compound that quickly evaporates into the air. Indoor benzene concentrations in Canadian homes are often higher than outdoor levels, with sources including vehicular emissions, industrial emissions, gasoline stations, wildfires, and residential wood burning.
(*) Proposed Guideline: The proposed long-term guideline value for benzene is 0.6 μg/m³.
(*) Indoor Levels: Median indoor benzene levels in multiple cities and two First Nations communities ranged from 0.4 to 2.2 μg/m³, with 95th percentiles ranging from 2.4 to 18.6 μg/m³. The national average outdoor benzene concentration in 2019 was 0.5 μg/m³. Many Canadian homes may have benzene levels exceeding the proposed guideline.
(*) Health Effects: Benzene is classified as a human carcinogen and is associated with acute myeloid leukemia and acute non-lymphocytic leukemia in adults. Evidence also suggests a link between benzene exposure and leukemia in children. Additionally, benzene exposure can lead to hematotoxicity, respiratory, reproductive, and developmental toxicity.
(*) Vulnerable Populations: Certain populations, such as smokers, South Asian Canadians, Indigenous women, and children, may be more vulnerable to the health effects of benzene exposure.
(*) Risk Management Recommendations: Health Canada recommends strategies to reduce indoor benzene exposure, including improving ventilation, avoiding the storage of gasoline and chemicals in the home or attached garage, proper sealing of containers, not smoking indoors, and ensuring proper installation and maintenance of fireplaces and wood stoves.
Link to the Canada Gazette, Part I, Volume 157, Number 39: Index