Assessment and remediation of radon and thoron radiation health hazard in mud-built homes in developing countries
Submitted to IGCP
Radioactive radon gas is being generated from uranium and thorium trace metals in soil. Dry, porous mud walls and floors of mud-built homes in developing countries emit radon into room air. Radiation damage in lung tissue results from two radon isotopes and their radioactive decay products. The longer-lived radon-222 with a half-life of ca. 3.8 days can be effectively diluted by venting with outside air. In contrast, radon-220 (called thoron) with a half-life of only ca. 55 seconds can only be mitigated by sealing of porous surfaces.
Typical tight sleeping quarters are often close to walls and floors where thoron originates. A high radiation dose may cause lung cancer. The thoron health hazard is unique to mud houses because porous mud surfaces are typically not sealed by gas-impermeable wall coverings or tiles.
Our project mainly focuses on: (1) developing recommendations for affordable and reasonable detection methods for radon and thoron in mud-built homes; (2) assessing the concentrations and distributions of thoron and radon in mud house air in Vietnam (as an example of developing countries); (3) affordable, non-toxic and socially acceptable sealing of porous mud surfaces in homes to prevent escape of thoron and radon, and to improve public health.