Health outcomes of low-dose ionizing radiation exposure among medical workers: a cohort study of the Canadian national dose registry of radiation workers.

Background: Medical workers can be exposed to low-dose ionizing radiation from various sources. The potential cancer risks associated with ionizing radiation exposure have been derived from cohort studies of Japanese atomic bomb survivors who had experienced acute, high-level exposure. Since such extrapolations are subject to uncertainty, direct information is needed on the risk associated with chronic low-dose occupational exposure to ionizing radiation.

Cigarette smoking and cancer risk: modeling total exposure and intensity.

A recent analysis showed that the excess odds ratio (EOR) for lung cancer due to smoking can be modeled by a function which is linear in total pack-years and exponential in the logarithm of smoking intensity and its square. Below 15-20 cigarettes per day, the EOR/pack-year increased with intensity (direct exposure rate or enhanced potency effect), suggesting greater risk for a total exposure delivered at higher intensity (for a shorter duration) than for an equivalent exposure delivered at lower intensity. Above 20 cigarettes per day, the EOR/pack-year decreased with increasing intensity (inverse exposure rate or reduced potency effect), suggesting greater risk for a total exposure delivered at lower intensity (for a longer duration) than for an equivalent exposure delivered at higher intensity.

An overview of the North American residential radon and lung cancer case-control studies.

Lung cancer has held the distinction as the most common cancer type worldwide since 1985 (Parkin et al., 1993). Recent estimates suggest that lung cancer accounted for 1.

A combined analysis of North American case-control studies of residential radon and lung cancer.

Cohort studies have consistently shown underground miners exposed to high levels of radon to be at excess risk of lung cancer, and extrapolations based on those results indicate that residential radon may be responsible for nearly 10-15% of all lung cancer deaths per year in the United States. However, case-control studies of residential radon and lung cancer have provided ambiguous evidence of radon lung cancer risks. Regardless, alpha-particle emissions from the short-lived radioactive radon decay products can damage cellular DNA.

Residential radon and risk of lung cancer: a combined analysis of 7 North American case-control studies.

Background: Underground miners exposed to high levels of radon have an excess risk of lung cancer. Residential exposure to radon is at much lower levels, and the risk of lung cancer with residential exposure is less clear. We conducted a systematic analysis of pooled data from all North American residential radon studies.

Decreases in occupational exposure to ionizing radiation among Canadian dental workers.

Objective: To describe doses of ionizing radiation and their possible associations with mortality rates and cancer incidence among Canadian dental workers.

Methods: The National Dose Registry (NDR) of Canada was used to assess occupational dose of ionizing radiation received by dental workers. The NDR cohort includes 42,175 people classified as dental workers.

Modeling seasonal variation in indoor radon concentrations.

Radon, a well-established risk factor for human lung cancer, is present at low concentrations in most homes. Consequently, many countries have established national guidelines for residential radon concentrations. In this article, we evaluate two models for describing seasonal variation in residential radon concentrations based on the data from a large case-control study conducted in Winnipeg, Canada.