Studies of radon-exposed miner cohorts using a biologically based model: Comparison of current Czech and French data with historic data from China and Colorado
Résumé
The biologically based two-stage clonal expansion (TSCE) model is used to analyze lung cancer in several miners studies, two new ones (Czech, French) and two historic ones (Chinese, Colorado). In all cases, the model assumptions are identical. An action of radiation on initiation, promotion, and transformation is allowed. While all four studies indicate a highly significant action of radiation on promotion, the action on initiation is not significant in the French cohort, and barely significant in the Colorado miners cohort. No action on transformation is found in the Colorado miners, while the other data sets indicate a borderline significance. The model can describe all the data sets adequately, with different model parameters. The observed patterns in exposure, time since beginning of exposure, birth year, age and calendar year are reproduced well. The doubling exposure rate for initiation is about 3.5 WLM/year in the new data sets, while it is higher in the historic data sets. For transformation the doubling rate is about 20 WLM/year for the new data sets, while again the historic data give higher estimates. The action of radiation on promotion is quite different in the four data sets. These differences also induce different risk estimates at low exposures. The larger power of the new studies at these low exposures, compared to the historic data requires less extrapolation when the risk at very low exposures is estimated. © Springer-Verlag 2004.
Mots clés
Relative Biological Effectiveness
Risk Assessment
Risk Factors
Biological organs
Cloning
Data acquisition
Health risks
Radiation
Radon
Data sets
Historic data
Lung cancer
Two-stage clonal expansion (TSCE)
Tumors
radon
age
article
birth
cancer risk
China
cohort analysis
controlled study
Czech Republic
human
lung cancer
male
malignant transformation
miner
observation
radiation exposure
reproducibility
time
United States
Age Distribution
Algorithms
Body Burden
Cohort Studies
Colorado
Computer Simulation
Dose-Response Relationship
France
Humans
Incidence
Lung Neoplasms
Mining
Models
Biological
Neoplasms
Radiation-Induced
Proportional Hazards Models
Radiation Dosage
Radiation Monitoring