RESUMEN
The Pooled Uranium Miners Analysis (PUMA) study is the largest uranium miners cohort with 119,709 miners, 4.3 million person-years at risk and 7754 lung cancer deaths. Excess relative rate (ERR) estimates for lung cancer mortality per unit of cumulative exposure to radon progeny in working level months (WLM) based on the PUMA study have been reported. The ERR/WLM was modified by attained age, time since exposure or age at exposure, and exposure rate. This pattern was found for the full PUMA cohort and the 1960 + sub-cohort, i.e., miners hired in 1960 or later with chronic low radon exposures and exposure rates. The aim of the present paper is to calculate the lifetime excess absolute risk (LEAR) of lung cancer mortality per WLM using the PUMA risk models, as well as risk models derived in previously published smaller uranium miner studies, some of which are included in PUMA. The same methods were applied for all risk models, i.e., relative risk projection up to <95 years of age, an exposure scenario of 2 WLM per year from age 18-64 years, and baseline mortality rates representing a mixed Euro-American-Asian population. Depending upon the choice of model, the estimated LEAR per WLM are 5.38 × 10-4 or 5.57 × 10-4 in the full PUMA cohort and 7.50 × 10-4 or 7.66 × 10-4 in the PUMA 1960 + sub-cohort, respectively. The LEAR per WLM estimates derived from risk models reported for previously published uranium miners studies range from 2.5 × 10-4 to 9.2 × 10-4. PUMA strengthens knowledge on the radon-related lung cancer LEAR, a useful way to translate models for policy purposes.
Asunto(s)
Neoplasias Pulmonares , Neoplasias Inducidas por Radiación , Enfermedades Profesionales , Exposición Profesional , Radón , Uranio , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Estudios de Cohortes , Radón/efectos adversos , Uranio/efectos adversos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/etiología , Exposición Profesional/efectos adversos , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Inducidas por Radiación/etiología , Proteínas Reguladoras de la Apoptosis , Enfermedades Profesionales/epidemiologíaRESUMEN
The presented study reports lung cancer mortality in a cohort of 11 842 subjects exposed to high levels of radon covering the period 1961-2010. Exposure estimates were based on one year measurements of radon progeny in most houses of the study area (72%), missing values in the studied area were replaced by measurements in proxy houses (9%) and exposures outside the area (19%) were based on country radon mapping. Mean concentration of 448 Bq m(-3) in the study is higher than the country mean by a factor of 5. By 2010, a total of 293 lung cancers were observed. The risk is significantly related to cumulated exposure with ERR/100Bq m(-3) 0.11 (90%CI: 0.04 - 0.25). This value is consistent with the risk coefficients in other indoor studies and also with the risks observed among uranium miners. The present follow-up demonstrated that increased incidence of lung cancer depends mainly on exposure from previous 5-19 years. The relative risk of lung cancer in the present study derived from this model is 1.53 (90%CI: 1.39 - 1.69).
Asunto(s)
Contaminantes Radiactivos del Aire/efectos adversos , Contaminación del Aire Interior/efectos adversos , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/epidemiología , Radón/efectos adversos , Adulto , Anciano , Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , República Checa/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Factores de TiempoRESUMEN
The biologically based two-stage clonal expansion (TSCE) model is used to analyze lung cancer mortality of European miners from the Czech Republic, France, and Germany. All three cohorts indicate a highly significant action of exposure to radon and its progeny on promotion. The action on initiation is not significant in the French cohort. An action on transformation was tested but not found significant. In a pooled analysis, the results based on the French and German datasets do not differ significantly in any of the used parameters. For the Czech dataset, only lag time and two parameters that determine the clonal expansion without exposure and with low exposure rates (promotion) are consistent with the other studies. For low exposure rates, the resulting relative risks are quite similar. Exposure estimates for each calendar year are used. A model for random errors in each of these yearly exposures is presented. Depending on the used technique of exposure estimate, Berkson and classical errors are used. The consequences for the model parameters are calculated and found to be mostly of minor importance, except that the large difference in the exposure-induced initiation between the studies is decreased substantially.
Asunto(s)
Neoplasias Pulmonares/mortalidad , Minería , Modelos Biológicos , Neoplasias Inducidas por Radiación/mortalidad , Exposición Profesional/análisis , Radón/análisis , Uranio , Artefactos , Estudios de Cohortes , Bases de Datos Factuales , Europa (Continente)/epidemiología , Humanos , Modelos Estadísticos , Proyectos de InvestigaciónRESUMEN
BACKGROUND: The Pooled Uranium Miners Analysis (PUMA) study draws together information from cohorts of uranium miners from Canada, the Czech Republic, France, Germany and the USA. METHODS: Vital status and cause of death were ascertained and compared with expectations based upon national mortality rates by computing standardized mortality ratios (SMRs) overall and by categories of time since first hire, calendar period of first employment and duration of employment as a miner. RESULTS: There were 51 787 deaths observed among 118 329 male miners [SMR = 1.05; 95% confidence interval (CI): 1.04, 1.06]. The SMR was elevated for all cancers (n = 16 633, SMR = 1.23; 95% CI: 1.21, 1.25), due primarily to excess mortality from cancers of the lung (n = 7756, SMR = 1.90; 95% CI: 1.86, 1.94), liver and gallbladder (n = 549, SMR = 1.15; 95% CI: 1.06, 1.25), larynx (n = 229, SMR = 1.10; 95% CI: 0.97, 1.26), stomach (n = 1058, SMR = 1.08; 95% CI: 1.02, 1.15) and pleura (n = 39, SMR = 1.06; 95% CI: 0.75, 1.44). Lung-cancer SMRs increased with duration of employment, decreased with calendar period and persisted with time since first hire. Among non-malignant causes, the SMR was elevated for external causes (n = 3362, SMR = 1.41; 95% CI: 1.36, 1.46) and respiratory diseases (n = 4508, SMR = 1.32; 95% CI: 1.28, 1.36), most notably silicosis (n = 814, SMR = 13.56; 95% CI: 12.64, 14.52), but not chronic obstructive pulmonary disease (n = 1729, SMR = 0.98; 95% CI: 0.93, 1.02). CONCLUSIONS: Whereas there are important obstacles to the ability to detect adverse effects of occupational exposures via SMR analyses, PUMA provides evidence of excess mortality among uranium miners due to a range of categories of cause of death. The persistent elevation of SMRs with time since first hire as a uranium miner underscores the importance of long-term follow-up of these workers.
Asunto(s)
Neoplasias Pulmonares , Enfermedades Profesionales , Exposición Profesional , Radón , Uranio , Canadá/epidemiología , Estudios de Cohortes , Europa (Continente)/epidemiología , Francia , Alemania , Humanos , Masculino , América del Norte/epidemiología , Exposición Profesional/efectos adversosRESUMEN
Fundamental estimates of radon-associated health risk have been provided by epidemiological studies of miners. In total, approximately 15 studies have been conducted worldwide since the 1960s. These results have contributed directly to radiological protection against radon. The present article summarises the main results, with a focus on analyses of miners exposed more recently, estimates of radon lifetime attributable risk, and interaction between radon and smoking. The potential for the upcoming Pooled Uranium Miner Analysis project to further improve our knowledge is discussed.
Asunto(s)
Carcinógenos Ambientales/efectos adversos , Exposición a la Radiación/prevención & control , Protección Radiológica/estadística & datos numéricos , Radón/efectos adversos , Humanos , Minería , Protección Radiológica/normasRESUMEN
The development of colorectal cancer in former Czechoslovakia and its successor states is illustrated using recorded mortality and from 1968 incidence rates retrieved from National Cancer Registry of Slovakia. The relatively high mortality rates in Czechoslovakia around 1950 contrasted with rates seen in other countries of central, southern and particularly of eastern Europe and were more close to those recorded in affluent countries of western Europe and northern America. Despite continuous stabilisation and decrease of this cancer in high risk countries from late 1970s the unexpected and gradual rise of incidence rates of colorectal cancer was recorded in Slovakia. During the period studied incidence rates rose by an annual mean percent change of 4,2 and 2,8 in colon and 2,2 and 1,0 in rectal cancer in males and females respectively. Beginning with the year 1995 colorectal cancer is the most common cancer in this country in both genders together. Study of the development of colorectal cancer at the levels of subsites indicated the higher rates but decreasing proportion of rectal cancer and increasing proportion of cases occurring in proximal colon. The importance of this new priority in diagnostics, treatment and control programmes is stressed.
Asunto(s)
Neoplasias Colorrectales/epidemiología , Factores de Edad , Neoplasias del Colon/epidemiología , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Incidencia , Masculino , Neoplasias del Recto/epidemiología , Sistema de Registros , Eslovaquia/epidemiologíaRESUMEN
The objective of the study was to investigate the contribution of dietary factors and physical exercise to the variation in the risk of lung cancer and its major histological types among men and women in the Czech Republic, and reveal interactions between smoking and diet/physical exercise, if any. In a hospital based case-control study, data collected by in-person interviews from 1096 microscopically confirmed lung cancer cases (587 women, 509 men) and 2966 controls were analyzed using unconditional logistic regression stratified by appropriate factors. Among all nonsmoking women protective effects were observed for black tea (OR=0.69), among all smoking women for wine (OR=0.71), physical exercise (OR=0.64) and vitamin supplements (OR=0.71). Among all men, inverse associations were found in smokers between lung cancer risk and frequent intake of fruits (OR=0.69) or moderate intake of spirits (OR=0.64), and a direct association for fat foods (OR=1.68). Comparing the effects of diet/physical activity on lung cancer risk among nonsmokers versus smokers, interactions with smoking appeared for the intake of black tea and milk/dairy products among women, and for moderate intake of spirits in men. When the effects of diet/physical exercise on risk were analyzed by major cell types in women, the intake of wine and physical exercise were inversely associated with the risk of both adenocarcinoma and small cell cancer, the intakes of fruits and vitamin supplements were inversely associated with the risk of squamous cell cancer. In men, the intake of fat foods was directly associated with the risk of squamous cell cancer, while the frequent intake of apples was inversely associated with the risk of both squamous- and small cell cancers. In men an inverse association with the risk of squamous cell cancer was found for the intake of other fruits. These data suggest that diet/physical exercise may affect the risk of lung cancer and major cell types, and that interactions between some dietary items and smoking may occur. Lung cancer is a multifactorial disease, since smoking, its main determinant, and other environmental and lifestyle factors interact with one another and with genetic factors to cause the disease.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Células Pequeñas/epidemiología , Dieta , Ejercicio Físico , Neoplasias Pulmonares/epidemiología , Adenocarcinoma/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de Células Escamosas/epidemiología , Medición de Riesgo , Factores de Riesgo , FumarRESUMEN
The cost-effectiveness of remedial and preventive countermeasures against indoor radon in the frame of the Czech Radon Programme is preliminarily estimated, resulting in 72 700 CZK and 194 000 CZK per y of life gained by remediation and prevention, respectively, (exchange rate approximately 28 CZK/EUR).
Asunto(s)
Contaminación del Aire Interior/economía , Contaminación del Aire Interior/prevención & control , Exposición a Riesgos Ambientales/economía , Exposición a Riesgos Ambientales/prevención & control , Política Pública , Protección Radiológica/economía , Radón/análisis , Radón/economía , Contaminación del Aire Interior/análisis , Análisis Costo-Beneficio , República Checa , Exposición a Riesgos Ambientales/análisis , Programas de Gobierno/economía , Programas de Gobierno/organización & administración , Proyectos Piloto , Monitoreo de Radiación/economía , Monitoreo de Radiación/métodos , Protección Radiológica/métodos , Protección Radiológica/estadística & datos numéricos , Estados UnidosRESUMEN
In 1993, ICRP-65 recommended that dose conversion of radon exposure should be based on the comparison of detriments between radon exposure and effective dose. The lifetime detriment from the radon exposure was projected according to the epidemiological studies of uranium miners then available. The projection model (GSF) was multiplicative with temporal and age-at-exposure modification. Since 1993, new studies of uranium miners have appeared and many original studies were updated. In addition, projections of the risk have been improved by including further modifying factors as for instance in BEIR VI. New analyses were completed in the Czech and French studies of uranium miners with accurate estimates of exposures based on extensive radon measurements. The resulting estimates of excess absolute lifetime risk per unit exposure in working level months (WLM) from these models lead to dose conversion of 10 mSv WLM(-1) for the BEIR VI model and 8 mSv WLM(-1) for the joint Czech-French model in contrast to the conversion of 5 mSv WLM(-1) for the GSF model.
Asunto(s)
Neoplasias Pulmonares/mortalidad , Modelos Biológicos , Neoplasias Inducidas por Radiación/mortalidad , Exposición Profesional/análisis , Exposición Profesional/estadística & datos numéricos , Radón/análisis , Medición de Riesgo/métodos , Simulación por Computador , Humanos , Incidencia , Internacionalidad , Minería/estadística & datos numéricos , Dosis de Radiación , Factores de Riesgo , Análisis de Supervivencia , Tasa de SupervivenciaRESUMEN
The European project Alpha-Risk aims to quantify the cancer and non-cancer risks associated with multiple chronic radiation exposures by epidemiological studies, organ dose calculation and risk assessment. In the framework of this project, mathematical models have been applied to the organ dosimetry of uranium miners who are internally exposed to radon and its progeny as well as to long-lived radionuclides present in the uranium ore. This paper describes the methodology and the dosimetric models used to calculate the absorbed doses to specific organs arising from exposure to radon and its progeny in the uranium mines. The results of dose calculations are also presented.
Asunto(s)
Neoplasias Pulmonares/mortalidad , Modelos Biológicos , Neoplasias Inducidas por Radiación/mortalidad , Exposición Profesional/análisis , Exposición Profesional/estadística & datos numéricos , Radón/análisis , Medición de Riesgo/métodos , Simulación por Computador , Humanos , Incidencia , Internacionalidad , Minería/estadística & datos numéricos , Dosis de Radiación , Factores de Riesgo , Análisis de Supervivencia , Tasa de Supervivencia , Uranio/análisisRESUMEN
UNLABELLED: The objective of the study is to estimate the differences in the impact of diet and physical exercise on lung cancer risk in female nonsmokers vs. smokers, and reveal interactions, if any. In a hospital based case-control study, data collected by in-person interviews from 569 female lung cancer cases and 2120 controls were analyzed using unconditional logistic regression stratifying by appropriate factors. Protective effects were observed for intake of milk/dairy products (OR=0.57, 95%CI 0.35-0.94), vegetables (OR=0.60, 95%CI 0.40-0.91), apples (OR=0.69), wine (OR=0.77), and physical exercise (OR=0.59, 95%CI 0.42-0.83) among smokers only, while no similar effects were found among nonsmokers. In contrast, the intake of black tea was associated with a protective effect (OR=0.66, 95%CI 0.47-0.94) among nonsmokers only. Comparing the effects of dietary items and physical activity on lung cancer risk among nonsmokers versus smokers, statistically significant effect modifications were found for black tea (P 0.005), and milk/dairy products (P 0.047). Borderline effect modifications emerged for physical exercise (P 0.077). CONCLUSIONS: These results indicate protective effects of some components of healthful diet and physical exercise among smokers, and of the intake of black tea among nonsmokers. The observed interactions of the impact of black tea, milk/dairy products and physical activity upon lung cancer risk in women at different levels of the smoking habit deserve further studies.
Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Neoplasias Pulmonares/etiología , Fumar/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Productos Lácteos , Dieta , Ejercicio Físico/fisiología , Femenino , Frutas , Humanos , Modelos Logísticos , Neoplasias Pulmonares/fisiopatología , Neoplasias Pulmonares/prevención & control , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Cese del Hábito de Fumar/estadística & datos numéricos , Encuestas y Cuestionarios , Té , Factores de Tiempo , VerdurasRESUMEN
BACKGROUND: Exposure to the radioactive gas radon and its progeny (222Rn and its radioactive decay products) has recently been linked to a variety of cancers other than lung cancer in geographic correlation studies of domestic radon exposure and in individual cohorts of occupationally exposed miners. PURPOSE: This study was designed to characterize further the risks for cancers other than lung cancer (i.e., non-lung cancers) from atmospheric radon. METHODS: Mortality from non-lung cancer was examined in a collaborative analysis of data from 11 cohorts of underground miners in which radon-related excesses of lung cancer had been established. The study included 64,209 men who were employed in the mines for 6.4 years on average, received average cumulative exposures of 155 working-level months (WLM), and were followed for 16.9 years on average. RESULTS: For all non-lung cancers combined, mortality was close to that expected from mortality rates in the areas surrounding the mines (ratio of observed to expected deaths [O/E] = 1.01; 95% confidence interval [CI] = 0.95-1.07, based on 1179 deaths), and mortality did not increase with increasing cumulative exposure. Among 28 individual cancer categories, statistically significant increases in mortality for cancers of the stomach (O/E = 1.33; 95% CI = 1.16-1.52) and liver (O/E = 1.73; 95% CI = 1.29-2.28) and statistically significant decreases for cancers of the tongue and mouth (O/E = 0.52; 95% CI = 0.26-0.93), pharynx (O/E = 0.35; 95% CI = 0.16-0.66), and colon (O/E = 0.77; 95% CI = 0.63-0.95) were observed. For leukemia, mortality was increased in the period less than 10 years since starting work (O/E = 1.93; 95% CI = 1.19-2.95) but not subsequently. For none of these diseases was mortality significantly related to cumulative exposure. Among the remaining individual categories of non-lung cancer, mortality was related to cumulative exposure only for cancer of the pancreas (excess relative risk per WLM = 0.07%; 95% CI = 0.01-0.12) and, in the period less than 10 years since the start of employment, for other and unspecified cancers (excess relative risk per WLM = 0.22%; 95% CI = 0.08-0.37). CONCLUSIONS: The increases in mortality from stomach and liver cancers and leukemia are unlikely to have been caused by radon, since they are unrelated to cumulative exposure. The association between cumulative exposure and pancreatic cancer seems likely to be a chance finding, while the association between cumulative exposure and other and unspecified cancers was caused by deaths certified as due to carcinomatosis (widespread disseminated cancer throughout the body) that were likely to have been due to lung cancers. This study, therefore, provides considerable evidence that high concentrations of radon in air do not cause a material risk of mortality from cancers other than lung cancer. IMPLICATIONS: Protection standards for radon should continue to be based on consideration of the lung cancer risk alone.
Asunto(s)
Minería , Neoplasias/mortalidad , Exposición Profesional/efectos adversos , Radón/efectos adversos , Adulto , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/inducido químicamenteRESUMEN
A brief description is given of the study of West Bohemian uranium miners, and recent and ongoing efforts to improve the quality of the data are summarized. Three recent analyses of the data from the cohort have led to rather different estimates of the excess relative risk of mortality from lung cancer per working-level month. The reasons for these different estimates are described, and it is concluded that estimates of lung cancer risk are strongly influenced by the quality of the exposure estimates, especially by the omission of some exposures accumulated during employment at other uranium mines, following the closure of most of the shafts at the original two mines. The most recent analysis has shown that, in common with other cohorts of radon-exposed miners, the excess relative risk of lung cancer per working-level month is modified by age and time since exposure. An inverse effect of exposure rate was also demonstrated, but it affected only men at very high concentrations and appears to be related to the time pattern of exposure. In addition, the risk was found to differ between the two main mines, possibly due to the influence of arsenic in the dust of the mines.
Asunto(s)
Neoplasias Pulmonares/etiología , Minería , Neoplasias Inducidas por Radiación/etiología , Radón/efectos adversos , Estudios de Cohortes , Humanos , Masculino , Riesgo , UranioRESUMEN
Few data are available to explain the continuing increase in lung cancer mortality among Czech women. The study was designed to examine the role of active smoking and other known or suspected factors. Data collected by personal interviews during the 15 months of a hospital-based case control study are reported. A total of 140 microscopically confirmed cases and 280 frequency-matched controls were analysed using multiple logistic regression. Cigarette smoking was the most important factor associated with excess risk for lung cancer among women. Significantly increased risk was found both among current smokers (OR=11.20, 95% CI 5.9-21.2), and ex-smokers (OR=10.02, 95% CI 5.5-18.4). Positive dose-response gradients (P<0.001) were observed between lung cancer risk and the daily number of cigarettes, duration of smoking, number of pack-years, inhaling, and grade of nicotine dependence assessed by the Fagerström test (Heatherton TF, Kozlowski LT, Frecker RC, Fagerström KO. Br J Addict 1991;86:1119-1470; Pomerleau OF. In: Bolliger CT, Fagerström KO, editors. The Tobacco Epidemic. Basle: Karger, 1997: 122-131). Exposure to environmental smoke was associated with elevated lung cancer risk (OR=3.58, for lifetime non-smokers exposed both in childhood and in adult age). Physical exercise and body mass index were inversely associated with lung cancer risk. For the category of physical exercise of more than 5 h per week, the odds ratio was 0.38, compared to subjects admitting no physical exercise. For body mass index, the odds ratio for the highest (compared to the lowest) quartile was 0.50. Chronic cough and phlegm (at least 3 months per year) were associated with excess risk (OR=6.07) only if their duration was less than 2 years before diagnosis of lung cancer, and, therefore, they were suspected of being more likely early symptoms of preclinical lung cancer rather than its cause. Our results support the statement that cigarette smoking is by far the most important cause of the on-going epidemic of lung cancer among Czech women, and are consistent with the concept of a balance between risk and protective factors whose eventual maintenance or alteration determine the development of disease (as suggested by Rylander R, Axelsson G, Andersson L, Liljequist T, Bergman B. Lung Cancer 1996;14(Suppl 1): S75-S83). Concerted control of smoking appears to be an urgent priority in lung cancer prevention among women, including specific approaches targeted on the female population.
Asunto(s)
Neoplasias Pulmonares/etiología , Fumar/efectos adversos , Salud de la Mujer , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Estudios de Casos y Controles , Checoslovaquia/epidemiología , Ejercicio Físico , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/prevención & control , Persona de Mediana Edad , Factores de RiesgoRESUMEN
Epidemiological evidence of lung cancer risk from radon is based mainly on studies of male miners. Recent results of one such study of Czech uranium miners who were restricted to lower exposure rates are reported. Two main factors that generally influence radiogenic risk of cancer, time since exposure and age at exposure, are analyzed. New analyses in the form of a relative risk model confirmed the strong decreasing effect with time since exposure that was observed earlier. In addition, a significant dependence on age at exposure was observed. This pattern of decreasing relative risk with increasing age at irradiation is consistent with observations in A-bomb survivors and irradiated patients. Similar analyses were performed for the two most frequent histological types of bronchogenic carcinoma, epidermoid and small cell. The general pattern of the risk for these two types was found to be similar to that for lung cancer overall. Nevertheless, differences were observed between these two types in the magnitude of the risk coefficients and in the latent period. The effect of radon exposure was found to be stronger but briefer for the small cell type. The effect of smoking was not examined in this study, as such data were not available.
Asunto(s)
Neoplasias Pulmonares/etiología , Minería , Neoplasias Inducidas por Radiación/etiología , Radón/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , República Checa , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Fumar/efectos adversosRESUMEN
Lung cancer mortality in a cohort of 4320 miners first employed during 1948-1959 at the Jáchymov and Horní Slavkov uranium mines in West Bohemia and followed until 1 January 1991 has been studied to gain a greater understanding of the consequences of exposure to radon and its progeny. Among men whose exposure rates never exceeded 10 working levels, excess relative risks per unit exposure were greater in younger men, and exposures received in the periods 15-24, 25-34 and 35+ years previously were found to have 47, 24 and 0% of the effect of exposures 5-14 years previously. Within this low-exposure-rate group excess relative risk increased linearly with time-weighted cumulative exposure and did not depend on exposure rate or duration of exposure. For men who spent less than 20% of their employment at the Jáchymov mine the excess relative risk per working level month was 1.36% (95% confidence interval 0.52-3.54) in the baseline category (age group 55+ and exposure received 5-14 years previously). For men who spent more than 20% of their employment at Jáchymov, the corresponding excess relative risk per working level month was higher by a factor of 1.80 (95% confidence interval 1.27-2.97). The difference may be due to the fact that men who spent more than 20% of their employment at Jáchymov were exposed to the much higher levels of arsenic in the dust at the Jáchymov mine than at other mines. When men with exposure rates above 10 working levels were included in the analysis, patterns of risk were complex and depended on both exposure rate and duration of exposure in addition to the factors mentioned above. If these findings are confirmed elsewhere, calculation of risk estimates for extrapolation to modern occupational or environmental exposures should be based on miners with exposure rates below about 10 working levels. Further investigation is desirable of the influence of dusts containing arsenic on lung cancer risk in miners exposed to radon.
Asunto(s)
Neoplasias Pulmonares/mortalidad , Minería , Neoplasias Inducidas por Radiación/mortalidad , Enfermedades Profesionales/mortalidad , Radón/efectos adversos , Adulto , Anciano , Checoslovaquia , Relación Dosis-Respuesta en la Radiación , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , UranioRESUMEN
Some recent estimates of lung cancer risk from exposure to radon progeny in homes have been based on models developed from a pooled analysis of 11 cohorts of underground miners exposed to radon. While some miners were exposed to over 10,000 working level months (WLM), mean exposure among exposed miners was 162 WLM, about 10 times the exposure from lifetime residence in an average house and about three times the exposure from lifetime residence at the "action level" suggested by the U.S. Environmental Protection Agency. The extrapolation of lung cancer risk from the higher exposures in the miners to the generally lower exposures in the home is a substantial source of uncertainty in the assessment of the risk of indoor radon. Using the pooled data for the miners, analyses of lung cancer risk were carried out on data restricted to lower exposures, either <50 WLM or <100 WLM. In the pooled data, there were 115 lung cancer cases among workers with no occupational WLM exposure and 2,674 among exposed miners, with 353 and 562 lung cancer cases in miners with <50 WLM and <100 WLM, respectively. Relative risks (RRs) for categories of WLM based on deciles exhibited a statistically significant increasing trend with exposure in each of the restricted data sets. In the restricted data, there was little evidence of departures from a linear excess relative risk model in cumulative exposure, although power to assess alternative exposure-response trends was limited. The general patterns of declining excess RR per WLM with attained age, time since exposure and exposure rate seen in the unrestricted data were similar to the patterns found in the restricted data. Risk models based on the unrestricted data for miners provided an excellent fit to the restricted data, suggesting substantial internal validity in the projection of risk from miners with high exposures to those with low exposures. Estimates of attributable risk for lung cancer (10-14%) in the U.S. from residential radon based on models from the unrestricted data were similar to estimates based on the data for miners receiving low exposures.
Asunto(s)
Contaminantes Radiactivos del Aire/efectos adversos , Exposición a Riesgos Ambientales , Vivienda , Neoplasias Pulmonares/etiología , Minería , Neoplasias Inducidas por Radiación/etiología , Exposición Profesional , Radón/efectos adversos , Uranio , Contaminantes Radiactivos del Aire/administración & dosificación , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Humanos , Neoplasias Pulmonares/mortalidad , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/mortalidad , Radón/administración & dosificación , Riesgo , Medición de RiesgoRESUMEN
A case-control study was conducted to investigate the relationship between diet and the risk of lung cancer among women non-smokers and to compare with women smokers in the same population. Data collected by personal interviews from 435 microscopically confirmed cases and 1710 controls were analysed using unconditional logistic regression. In addition to results for all study subjects, associations between diet and lung cancer risk were compared between two highly contrasting groups: smokers (odds ratio (OR) 7.03) and non-smokers (OR 1.00). A protective effect of frequent (daily or several times per week) black tea drinking appeared among non-smoking women (OR 0.65, 95% confidence interval (CI) 0.43-0.99). Among smoking women, protective effects were observed for frequent intake of milk/dairy products (OR 0.56, 95% CI 0.32-0.96), coffee (OR 0.47, 95% CI 0.25-0.88), and wine consumption (daily or weekly OR 0.60, 95% CI 0.37-0.98; monthly OR 0.60, 95% CI 0.39-0.94). Inverse associations with the risk appeared for physical exercise for smokers only, and for the body mass index both among non-smoking and smoking women. Some items of diet may contribute to variation in risk among women in the Czech Republic; their importance seems to vary in relation to their status in smoking, the dominant factor in the aetiology of lung cancer.
Asunto(s)
Dieta , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/etiología , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Estudios de Casos y Controles , República Checa/epidemiología , Ejercicio Físico , Femenino , Encuestas Epidemiológicas , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Análisis de Regresión , Medición de RiesgoRESUMEN
First epidemiological evidence of lung cancer risk from exposure to radon was based on studies of uranium miners. The risk in other mines was reported later. The cohort study among 2466 Czech tin miners was conducted in order to estimate the size of the risk and to compare it to that in uranium mines. Based on 205 lung cancers, the estimate of excess relative risk per unit exposure in the simple linear model 0.011 is compatible with findings from two cohort studies of Czech uranium miners. This similarity holds in more complex models that include modifying effects of age and time since exposure. In addition, an alternative description of the risk in terms of lifetime risk was used. This approach provides summarized characteristics, in which modifying effects of time and age are incorporated. The attributive risk derived from the lifetime relative risk is proportional to cumulated exposure observed in both tin and uranium miners. On the other hand, the expected life shortening of 19 years among radiation induced deaths is similar in these studies.
Asunto(s)
Neoplasias Pulmonares/epidemiología , Minería , Neoplasias Inducidas por Radiación/epidemiología , Enfermedades Profesionales , Exposición Profesional , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Contaminantes Radiactivos del Aire , Contaminación Radiactiva del Aire , Carcinógenos Ambientales , Estudios de Cohortes , República Checa , Humanos , Neoplasias Pulmonares/etiología , Persona de Mediana Edad , Radón , Hijas del Radón , Riesgo , Factores de Tiempo , Estaño , UranioRESUMEN
To investigate the relationship between diet, physical activity, and the risk of lung cancer among female nonsmokers, and to compare it with female smokers in the same population, we conducted a case-control study. Data collected by personal interviews from 419 cases and 1593 controls were analyzed using unconditional logistic regression. As expected, among 130 nonsmoking cases, adenocarcinoma was the predominant cell type (49.2%), followed by squamous cell (20.2%) and small cell cancers (10.5%). The corresponding figures for 289 smoking cases were 29.3%, 27.5%, and 28.2%, respectively. Excess lung cancer risk was associated with consumption of red meat among nonsmokers (OR=2.20, 95%CI 1.07--4.51). Protective effects were observed for vegetables (OR=0.61, 95%CI 0.39--0.96), apples (OR=0.67, 95%CI 0.48--0.95), milk/dairy products (OR=0.54, 95%CI 0.32--0.93), coffee (OR=0.56, 95%CI 0.34--0.91), and wine (OR=0.69, 95%CI 0.49--0.98) among smokers only, and for black tea (OR=0.67, 95%CI 0.46--0.99) among nonsmokers only. An inverse association with risk emerged for physical exercise (or sport, walking), among smokers only. Some items of diet and physical activity appear to be important factors contributing to variation in lung cancer risk among women in the Czech Republic, however, their effects in nonsmokers may differ from those in smokers.