Effective dose coefficients for inhaled radon and its progeny: ICRP’s approach

The International Commission on Radiological Protection (ICRP) has recently published three reports on radon exposure: (i) Publication 115 on lung cancer risks from radon and radon progeny [1], (ii) Publication 126 on radiological protection against radon exposure [2] and (iii) Publication 137 on Occupational Intakes of Radionuclides (OIR), Part 3 [3]. The latter document gives doses coefficients for the inhalation of radon, thoron and their airborne progeny as well as recommendations for their use for the protection of workers. As with all other radionuclides, the effective dose coefficients are calculated with ICRP reference biokinetic and dosimetric models. Sufficient information and dosimetric data are given so that site-specific dose coefficients can be calculated based on measured aerosol parameter values

Risk of lung cancer mortality in nuclear workers from internal exposure to alpha particle-emitting radionuclides

BACKGROUND: Carcinogenic risks of internal exposures to alpha-emitters (except radon) are poorly understood. Since exposure to alpha particles-particularly through inhalation-occurs in a range of settings, understanding consequent risks is a public health priority. We aimed to quantify dose-response relationships between lung dose from alpha-emitters and lung cancer in nuclear workers. METHODS: We conducted a case-control study, nested within Belgian, French, and UK cohorts of uranium and plutonium workers. Cases were workers who died from lung cancer; one to three controls were matched to each. Lung doses from alpha-emitters were assessed using bioassay data. We estimated excess odds ratio (OR) of lung cancer per gray (Gy) of lung dose. RESULTS: The study comprised 553 cases and 1,333 controls. Median positive total alpha lung dose was 2.42 mGy (mean: 8.13 mGy; maximum: 316 mGy); for plutonium the median was 1.27 mGy and for uranium 2.17 mGy. Excess OR/Gy (90% confidence interval)-adjusted for external radiation, socioeconomic status, and smoking-was 11 (2.6, 24) for total alpha dose, 50 (17, 106) for plutonium, and 5.3 (-1.9, 18) for uranium. CONCLUSIONS: We found strong evidence for associations between low doses from alpha-emitters and lung cancer risk. The excess OR/Gy was greater for plutonium than uranium, though confidence intervals overlap. Risk estimates were similar to those estimated previously in plutonium workers, and in uranium miners exposed to radon and its progeny. Expressed as risk/equivalent dose in sieverts (Sv), our estimates are somewhat larger than but consistent with those for atomic bomb survivors.See video abstract at, http://links.lww.com/EDE/B232

Projecting the time trend of thyroid cancers: its impact on assessment of radiation-induced cancer risks.

International audienceThe incidence of thyroid cancer, which may be induced by ionizing radiation, has been rising in most Western countries for more than 20 years. In France, public worry about this increase and its possible connection with the fallout from Chernobyl led the government to ask for an evaluation of the health impact of this accident and an assessment of the feasibility of an epidemiological study. These requests raise two methodological questions: Which risk model should be used to relate exposure to risk? What is known about the spontaneous incidence rate of thyroid cancers? This article analyzes the impact of the time trend in the spontaneous incidence of thyroid cancers over the past 20 years in France when evaluating the risk of radiation-induced cancer. Age-period-cohort models were used to model the trend of spontaneous incidence from 1978 through 1997 and then to apply two scenarios for projections up to 2007: one with a constant incidence, the other using the trend observed over the past 20 years. Then the risk was assessed for a hypothetical population of 30,000 children aged 0 to 15 y, exposed to a hypothetical 0.1 Gy thyroid dose. The analysis shows that consideration of the trend instead of a constant spontaneous incidence can yield substantial differences in the risk estimates for thyroid cancer

Effective dose coefficients for inhaled radon and its progeny: ICRP’s approach

The International Commission on Radiological Protection (ICRP) has recently published three reports on radon exposure: (i) Publication 115 on lung cancer risks from radon and radon progeny [

Misspecification of within-area exposure distribution in ecological Poisson models

International audienc

Projecting the time trend of thyroid cancers: its impact on assessment of radiation-induced cancer risks.

International audienceThe incidence of thyroid cancer, which may be induced by ionizing radiation, has been rising in most Western countries for more than 20 years. In France, public worry about this increase and its possible connection with the fallout from Chernobyl led the government to ask for an evaluation of the health impact of this accident and an assessment of the feasibility of an epidemiological study. These requests raise two methodological questions: Which risk model should be used to relate exposure to risk? What is known about the spontaneous incidence rate of thyroid cancers? This article analyzes the impact of the time trend in the spontaneous incidence of thyroid cancers over the past 20 years in France when evaluating the risk of radiation-induced cancer. Age-period-cohort models were used to model the trend of spontaneous incidence from 1978 through 1997 and then to apply two scenarios for projections up to 2007: one with a constant incidence, the other using the trend observed over the past 20 years. Then the risk was assessed for a hypothetical population of 30,000 children aged 0 to 15 y, exposed to a hypothetical 0.1 Gy thyroid dose. The analysis shows that consideration of the trend instead of a constant spontaneous incidence can yield substantial differences in the risk estimates for thyroid cancer