Methodology developed to make the Quebec indoor radon potential map.

Area of Science:

• Environmental Science
• Geochemistry
• Public Health

Background:

• Indoor radon exposure poses a significant health risk.
• Identifying radon-prone areas is crucial for public health management.
• The Quebec Ministry of Health requires a map to assess indoor radon risks.

Purpose of the Study:

• To develop a predictive map of indoor radon potential in Quebec.
• To combine radiogeochemical data with indoor radon measurements for accurate risk assessment.
• To identify areas with high indoor radon potential for targeted interventions.

Main Methods:

• Combined airborne gamma-ray surveys (equivalent uranium), sediment uranium concentrations, and geology data.
• Utilized 3082 basement radon concentration measurements.
• Applied Kruskal-Wallis one-way ANOVA to determine thresholds and combine datasets into a predicted radon potential map.

Main Results:

• Four statistically significant radon potential levels were identified: low, medium, high, and very high.
• Proportions of dwellings exceeding the Canadian radon guideline (200 Bq/m³) increased with radon potential levels (10% low, 45% very high).
• The predictive map accurately identified radon-prone areas, validated by confirmed radon exposure data.

Conclusions:

• The radiogeochemical-based predictive map is reliable for identifying radon-prone areas in Quebec.
• This approach is effective even in regions lacking indoor radon measurements.
• The map supports public health efforts in managing indoor radon exposure risks.