Abstract
Managing worker exposures associated with rare earth element (REE) mining will require increased attention as Canada enters the global market. Components manufactured from REEs are essential to a variety of electronics and green energy technologies. The growing demand for these products has resulted in an increasing number of production projects outside China, currently the world’s largest producer. Canada has some of the largest known REE reserves in the world; over 50 exploration projects are in development, the first of them entering production last year. However, it is important to understand the unique occupational health risks of REE mining. These include the REEs themselves, and naturally-occurring radioactive elements uranium and thorium that often occur in REE deposits, which will be the focus of this presentation. Limited research has been conducted on the toxicity of the 17 elements known collectively as the “rare earth elements”, and subsequently there is a lack of published occupational exposure limits (OELs). A summary of the health effects associated with exposure to REEs will be presented, along with strategies to assess and control exposures. Radiation exposure resulting from the decay of uranium and thorium is assessed through estimating worker doses from the following pathways: inhalation of radon gas and its radioactive decay products, inhalation of long-lived radioactive dust, external gamma radiation, and ingestion of radioactive material from surface contamination. The methods for conducting an initial radiation assessment will be presented, along with management approaches based on guidelines by Health Canada. The early assessment of risks and adoption of best practices to limit harmful exposures will help create a healthy workforce and ensure Canada emerges as a responsible leader in this rapidly expanding industry.