郑州市1991-1995年放射工作人员个人剂量监测结果与分析

本文报导了１９９１－１９９５年用热释光方法对郑州市６１１名放射工作人员个人剂量监测的结果。结果表明，医用诊断Ｘ线、核医学、放射治疗、工业探伤、教学科研人员的五年年均剂量当量依次为：３．２０５ｍＳｖ，６．０３１ｍＳｖ，５．０１６ｍＳｖ，２．７３ｍＳｖ，４．０４６ｍＳｖ．６１１名放射工作人员中，９１．５％的人员受照剂量低于年限值的十分之一，受照剂量大于１５ｍＳｖ的人员小于职业人员总数的０．４４％，几年系统监测未发现超过国家标准限值５０ｍＳｖ。     

牡丹江市1991—1995年放射工作人员外照射剂量监测水平与评价

本文介绍了牡丹江市采用热释光测量方法对放射工作人员外照射个人剂量监测结果进行分析。结果表明，在１９９１￣１９９５年期间牡丹江市放射工作人员的平均年剂量当量为０．９６￣１．２８ｍＳｖ，低于国家标准所规定的剂量当量限值５０ｍＳｖ的十分之一，按职业分类：工业探伤人员的年平均剂量当量高于医疗放射人员的年平均剂量当量，并对剂量较高的放射工作单位提出相应的改进意见和个人防护措施。     

江门市放射工作人员职业外照射个人剂量水平的调查

目的 了解江门市放射工作人员职业外照射的个人剂量水平。方法 按《放射工作人员个人剂量监测方法》（ＧＢ５２９４－８５）要求,监测周期为３个月,一共４期。结果 江门市放射工作人员人均年剂量当量为１．１７ｍＳｖ／ａ,其中医用诊断Ｘ射线从业人员为１．４０ｍＳｖ／ａ,工业探伤为０．４１ｍＳｖ／ａ,密封源其它应用为０．３２ｍＳｖ／ａ,镇医院为２．４９ｍＳｖ／ａ。结论 江门市放射工作人员人均年剂量当量远低于个人     

山西省放射工作人员外照射个人剂量水平研究

本文报道了山西省１９８７年～１９９２年用热释光方法监测的职业外照射个人剂量水平。尤其对１９９０年３１２４名职业人员的受照剂量作了分析，结果年剂量最高为１１１．５ｍＳｖ，均值为１．７９ｍＳｖ。按职业分类：医用诊断Ｘ射线、核医学、放射治疗、工业探伤、地质物探、教学科研及其它人员的平均年剂量依次为１．９５ｍＳｖ，１．１７ｍＳｖ，０．９２ｍＳｖ，２．１３ｍＳｖ，１．７３ｍＳｖ，０．６４ｍＳｖ和１．１５ｍＳｖ。在３１２４名职业人员中，有０．３％人员的年剂量超过了国家基本限值（５０ｍＳｖ）；但９５％人员的年剂量没超过该限值的３／１０；８９．８％人员的年剂量没超过该限值的１／１０；文中还对较大剂量的原因进行了分析，并与不同地区的监测结果作了比较     

山西省1995—1997年放射工作人员外照射个人剂量监测结果分析

本文主要介绍了山西省在１９９５￣１９９７年期间，对２８２８名放射工作人员进行了外照射个人剂量监测。监测结果表明：放射工作人员年均剂量当量水平呈逐年下降趋势，依次为２．７１ｍｓｖ、２．１０ｍｓｖ、２．０７ｍｓｖ。９９．６１％的人员所受照剂量在所剂量限值（５０ｍｓｖ）以下。９１．３４％的人员年均剂量当量低于限值的１／１０。９７．９１％的人低于限值的３／１０。不同工种的个人剂量水平以工业探伤工作人员的年     

放射治疗作业人员剂量负荷与分布

本文主要报道广东省１９９３、１９９４两个年度放射治疗作业人员个人剂量监测结果。两个年度的监测比分别为７５．４％、８０．４％。该两年度的平均年剂量当量分别为０．３５ｍＳｖ和０．４１ｍＳｖ，集体剂量当量分别为１６１ｍａｎｍＳｖ和２１１．６ｍａｎｍＳｖ。医护人员和技术人员的平均年剂量当量１９９３年度分别为０．３１ｍＳｖ、０．３７ｍＳｖ，１９９４年度分别为０．３５ｍＳｖ、０．４６ｍＳｖ。     

阳江天然放射性高本底地区放射流行病学调查概况

笔者综合报道了１９７２～１９９０年广东阳江天然放射性高本底地区（ＨＢＲＡ）放射流行病学调查主要结果，用多种测试仪器测定了环境γ辐射，说明ＨＢＲＡ居民所受外照射年平均照射量率为３３０ｍＲ，全身内外照射年有效剂量当量为６．４ｍＳｖ，对照地区（ＣＡ）相应为１１４ｍＲ和２．４ｍＳｖ，对本底辐射以外环境和宿主的可能致癌与致突变因素的研究表明，两地区基本符合“齐同对比”原则，两人群是可比的，根据对ＨＢＲＡ１７     

海盐县放射工作人员健康状况调查

为了保障放射工作人员身体健康 ,根据《放射工作人员健康管理规定》 ,我们对本县境内放射工作单位的 5 3名工作人员进行了健康状况调查 ,现将结果报告如下。对象与方法1.调查对象 :医用放射诊断工作人员 30名 ,工业探伤工作人员 2 3名 ;其中男性 49人 ,女性 4人 ;年龄最小2 1岁 ,最大 6 0岁 ,平均年龄 35 4岁 ;放射工龄 :最短 6个月 ,最长 37年 ,平均工龄 12 3年。2 .接触射线情况 :根据 1998年放射工作人员剂量监测结果 ,年平均剂量 1 5 2 0ｍＳｖ/ａ,与浙江省 1991～ 1995年平均剂量 1 6 46ｍＳｖ/ａ相近 ,绝大多数在 0 4ｍＳｖ～ 3 6…     

锶-90/钇-90敷贴器γ、X射线的来源及所致医护人员的剂量

探讨了在各大医院治疗皮肤病用的锶－９０／钇－９０敷贴器γ、Ｘ射线的来源。通过理论计算及实测值，估算了医护人员所接受的外照射年有效剂量为２ｍＳｖ，仅为放射性工作人员年剂量限值的４％。     

天津市放射工作人员7年个人剂量监测结果评价

本文介绍了天津市１９８８年－１９９４年期间，放射工作人员外照射个人剂量监测结果。其结果表明：天津市放射工作人员外照射个人剂量水平以１９８８年的年均剂量当量１．５０５９ｍＳｖ为最高，以后呈逐年下降趋势。其主要原因是加强了各种防护措施，如各种射线装置的防护改造、Ｘ线机的更新，辐射防护知识的普及等。     

Radon daughter exposure to uranium miners

Radon exposures to U.S. uranium miners under present conditions average about 1.3 WLM per year approximately or equal to 60 WLM per full working lifetime. This is intermediate between (a) the lowest exposures for which there have been excess lung cancers reported among U.S. miners (120-240 WLM) and (b) average environmental radon exposures (16 WLM), so models based on these two situations are used to estimate expected effects on present uranium miners. In Model A, the loss of life expectancy is 45 days, the SMR (standardized mortality ratio) for lung cancer is 1.10, and the SMR for all causes between ages 18 and 65 is 1.013. In Model B these are 10 days, 1.03 and 1.002 respectively. It is shown that the radon exposures to miners are similar to those to millions of Americans from environmental exposure, and that miner health risks are comparable to those of other radiation workers. Their lung cancer risk from radon is 7-50 times less than their job-related accident mortality risk, and represents 0.7-4% of their total risk in mining. Miners suffer from many diseases with SMR very much larger than that for radon-induced lung cancer, and there are many other occupations and industries with far higher SMR for lung cancer than that from radon exposure to miners.     

Radon: characteristics in air and dose conversion factors

The dose conversion factor (DCF) which gives the relationship between effective dose and potential alpha energy concentration of inhaled short-lived radon decay products is calculated with a dosimetric approach. The calculations are based on a lung dose model with a structure that is related to the new recommended ICRP respiratory tract model. The characteristics of the radon decay products concerning the unattached fraction and the activity size distribution of the radon decay products are important input quantities for the calculation of DCF. Experimental data about these parameters obtained from measurements in homes, at working places, and in the free atmosphere at ground level in the last past years are summarized. Taking into account the measured aerosol characteristics the DCF fractions of the unattached (DCFu) and aerosol-attached (DCFae) radon decay products for different places were calculated. Variation of DCF for different places were caused dominantly by the variation of DCFu of the unattached radon clusters (0.3-32 mSv WLM(-1)). Nose inhalation drastically reduced (about a factor 4) the dose contribution by the unattached cluster. The dose fraction by the radon decay product aerosol (DCFae) varies between 4-10 mSv WLM(-1). Taking into account a relative sensitivity distribution between bronchial, bronchiolar and alveolar regions of the thoracic lung with 0.80:0.15:0.05 and nose breathing the DCF of most of the working places (inhalation rate: 1.2 m3 h(-1)) vary between 5.7-6.7 mSv WLM(-1) depending on the number concentration of the aerosol particles. The DCF-value of 4.2 mSv WLM(-1) for the general public in dwellings with higher aerosol concentration (>4 x 10(4) particles cm(-3)) has about the same value as recommended by ICRP 65 (1994b). Significantly higher are the DCF-values for "normal" aerosol conditions indoors (5 x 10(3)-4 x 10(4) particles cm(-3)) and in the open air (7.3 mSv WLM(-1) and 9.7 mSv WLM(-1)).     

Lung cancer risk among former uranium miners of the WISMUT Company in Germany

After 1946, the WISMUT Company developed the third-largest uranium-mining province in the world in the German Democratic Republic. METHODS: A case-control study among former WISMUT miners was conducted to investigate the lung cancer risk in relation to attained age, time since exposure, exposure duration, and exposure rate. It consisted of 505 patients with lung cancer and 1,073 controls matched to cases according to the year of birth. The cumulative exposure to radon and radon decay products was calculated as the sum of yearly exposures and expressed in Working Level Months (WLM). Cases had a mean cumulative exposure of 552 WLM compared to 420 WLM in controls. RESULTS: There was a statistically significant increase in lung cancer risk for cumulative exposures above 800 WLM. Under the assumption of a linear risk model, there was a significant increase in the relative risk of 0.10 per 100 WLM after adjusting for smoking and asbestos exposure. For current smokers the increase in relative risk was lower (0.05 per 100 WLM), whereas it was higher (0.20 per 100 WLM) among nonsmokers and longtime ex-smokers. After correcting in a sensitivity analysis for the fact that the controls of this study had a higher average exposure than the population of WISMUT workers they were recruited from, the adjusted ERR increased to 0.24 per 100 WLM. Lung cancer risk declined with time since exposure, except for exposures received 45 or more years ago. No inverse dose rate effect was observed.     

Lung cancer risk associated to exposure to radon and smoking in a case-control study of French uranium miners

A case-control study nested in the cohort of French uranium miners took smoking information into account in investigating the effect of radon exposure on lung cancer risk. This study included 100 miners who died of lung cancer and 500 controls matched for birth period and attained age. Data about radon exposure came from the cohort study, and smoking information was retrospectively determined from a questionnaire and occupational medical records. Smoking status (never vs. ever) was reconstructed for 62 cases and 320 controls. Statistical analyses used conditional logistic regression. The effect of radon exposure on lung cancer risk was assessed with a linear excess relative risk model, and smoking was considered as a multiplicative factor. Mean cumulative radon exposures were 114.75 and 70.84 Working Level Months (WLM) among exposed cases and controls, respectively. The crude excess risk of lung cancer per 100 WLM was 0.98 (95% CI: 0.18-3.08%). When adjusted for smoking, the excess risk was 0.85 per 100 WLM (95% CI: 0.12-2.79%), which is still statistically significant. The relative risk related to smoking was equal to 3.04 (95% CI: 1.20-7.70). This analysis shows a relative risk of lung cancer related to smoking similar to that estimated from previous miners' cohorts. After adjustment for smoking, the effect of radon exposure on lung cancer risk persists, and its estimated risk coefficient is close to that found in the French cohort without smoking information.     

Feasibility study for a long-term follow-up in a historical cohort of Brazilian coal miners.

The first Brazilian historical mortality cohort study on miners was conducted. The cohort consisted of 3224 workers in the underground coal mining industry in southern Brazil. This industry has been operating since 1942 without compliance with any regulatory standards, since there were no relevant national regulations. Over almost 60 years, about 5000 workers were exposed to high levels of radiation. However, later radiation exposure was significantly reduced, particularly that due to radon exposure. Recent radon concentration measurements indicated an average annual exposure to radon progeny of 2.1 WLM, ranging from 0.2 to 7.2 WLM. As radon exposure in the past was unknown, it can be suggested that mine workers have not been working safely as regards the health hazard related to radon and radon progeny exposure. The cohort inclusion criteria are as follows: (a) all male employees who had worked for at least one year at the coal mine; (b) workers with complete workplace information (underground and surface); (c) employment hiring between 1945 and 1997 and (d) the worker must have been alive on 1 January 1979. Through multiple strategies of search it was possible to follow up the members of the cohort with a success rate of 92%. This paper presents the characteristics of the study population and provides information about the feasibility of conducting a retrospective mortality study in Brazil, taking into account the methodological and logistical difficulties of conducting such a study in a developing country.     

Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. Ever use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.     

寿光日光温室春秋季氡浓度变化趋势及辐射剂量估算

目的初步了解日光温室中氡浓度的本底值和变化趋势,估算温室作业人员氡及其子体造成的年均辐射剂量,探讨温、湿度对氡浓度的影响。方法 2009年5月和10月分别对选定的2座温室进行调查,使用Model1027连续测氡仪和干湿球温度计对温室环境中的氡浓度、温度和相对湿度进行8h连续监测。结果在测定范围内,5月温室氡浓度、温湿度最大值分别为355.0Bq/m3、30.5℃和93%,10月各指标的最大值分别为235.4Bq/m3、37.5℃和72%;根据实际情况粗略估算的温室作业人员年均辐射剂量为0.8686mSv。结论温度和相对湿度可能是影响温室中氡浓度的重要因素;温室作业人员由于职业因素所造成的氡及其子体的辐射剂量略高于当地平均室内暴露所造成的辐射剂量,氡子体对作业人员健康的影响应引起重视。     

Lifetime risk of lung cancer due to radon exposure projected to Japanese and Swedish populations

Lifetime risk projections depend greatly on both background lung cancer rates and the selection of the risk model. Since background lung cancer rates differ from subject populations and the time, etiological risk of lifetime lung cancer mortality per unit radon exposure in WLM should be estimated for each subject population and the time of interest. To answer quantitatively how much are the differences among the projected risks for different populations, the Swedish case-control-study-based risk projection model was applied to the Japanese and Swedish populations from 1962 to 1997 as subject populations because of their distinct trends of lung cancer rates. To compare the results with the reference population and authorized risk projection models, U.S. population 1997 and the two risk projection models in BEIR VI report were applied, respectively. Lifetime risk of lung cancer mortality projected for Japanese, Swedish, and U.S. populations in 1997 per radon progeny exposure were estimated to range from 1.50 (0.40-3.19) x 10(-4) WLM(-1) to 9.86 (2.62-20.9) x 10(-4) WLM(-1), which could be compared to the detriment associated with a unit effective dose. Conclusive dose conversion coefficients in this study ranged from 2.05 (0.55-4.37) to 13.5 (3.59-28.6) mSv WLM(-1), and within this range the discrepancy between dosimetric and epidemiological approaches was included.     

Mortality of a cohort of tin miners 1941-86.

The mortality patterns of United Kingdom tin miners were examined in relation to calendar period and duration of underground work with particular attention to lung cancer and exposure to radon. Subjects were all men who had worked for at least one year between 1941 and 1984 at one of two United Kingdom tin mines and for whom a complete work history could be constructed from mine records. Standardised mortality ratios (SMRs) were calculated using national (England and Wales) rates. The pattern of SMRs in relation to potential explanatory variables was analysed using Poisson regression methods. Mortalities from lung cancer and silicosis (including silicotuberculosis) were significantly raised and showed a significant relation with duration of underground work (mortality from stomach cancer was raised in both underground and surface workers, but not significantly). Excess mortality from silica related disease declined steeply from 35% among workers first exposed before 1920 to 1% among those first exposed after 1950. Thirteen surface workers with known exposure to arsenic had high rates of lung and stomach cancer. The SMR for lung cancer showed a consistent pattern in relation to duration of underground exposure, rising from 83 (observed/expected = 8/9.6) for surface workers (without exposure to arsenic) to 447 (15/3.4) for workers with more than 30 years underground exposure. Examination of the SMR for lung cancer by total underground exposure, age, and time since last exposure gave rise to a model for the expression of risk which depends only on total exposure and time since exposure. The fitted model implies that the effect of exposure to radon in a given year has no effect on risk for 10 years, then rapidly rises to a maximum from which the excess risk then declines, halving every 4.3 years. There were no direct measurements of historic radon levels. A conservative estimate based on measurements taken since 1969 by the National Radiological Protection Board and the Mines and Quarries Inspectorate is that the annual dose to an underground worker was about 10 working level months (WLM). Given this assumption, the risk/exposure slope implied by the present data, and the model fitted to it, was somewhat lower than that given in the fourth Committee on the Biological Effects of Ionisation Radiation (BEIR IV) report (about 40% lower for lifetime exposures). The present data also imply different risks depending on the age at exposure, with relatively higher lifetime risks for exposure at older ages, and relatively lower risks for exposures at younger ages. In conclusion, there was a clear relation between exposure to radon and death from lung cancer. The relative risk of lung cancer due to exposure to radon was not constant in cessation of exposure. The lifetime excess risk of lung cancer implied by these data for 40 years exposure at the current statutory limit of four WLM a year starting at age 20, was about 8% (79 excess deaths per 1000 exposed), assuming average smoking habits among the exposed workers. Control of dust concentrations in the mines has substantially reduced--and may have eliminated--direct mortality from silica related disease.     

Mortality of a cohort of tin miners 1941-86

The mortality patterns of United Kingdom tin miners were examined in relation to calendar period and duration of underground work with particular attention to lung cancer and exposure to radon. Subjects were all men who had worked for at least one year between 1941 and 1984 at one of two United Kingdom tin mines and for whom a complete work history could be constructed from mine records. Standardised mortality ratios (SMRs) were calculated using national (England and Wales) rates. The pattern of SMRs in relation to potential explanatory variables was analysed using Poisson regression methods. Mortalities from lung cancer and silicosis (including silicotuberculosis) were significantly raised and showed a significant relation with duration of underground work (mortality from stomach cancer was raised in both underground and surface workers, but not significantly). Excess mortality from silica related disease declined steeply from 35% among workers first exposed before 1920 to 1% among those first exposed after 1950. Thirteen surface workers with known exposure to arsenic had high rates of lung and stomach cancer. The SMR for lung cancer showed a consistent pattern in relation to duration of underground exposure, rising from 83 (observed/expected = 8/9.6) for surface workers (without exposure to arsenic) to 447 (15/3.4) for workers with more than 30 years underground exposure. Examination of the SMR for lung cancer by total underground exposure, age, and time since last exposure gave rise to a model for the expression of risk which depends only on total exposure and time since exposure. The fitted model implies that the effect of exposure to radon in a given year has no effect on risk for 10 years, then rapidly rises to a maximum from which the excess risk then declines, halving every 4.3 years. There were no direct measurements of historic radon levels. A conservative estimate based on measurements taken since 1969 by the National Radiological Protection Board and the Mines and Quarries Inspectorate is that the annual dose to an underground worker was about 10 working level months (WLM). Given this assumption, the risk/exposure slope implied by the present data, and the model fitted to it, was somewhat lower than that given in the fourth Committee on the Biological Effects of Ionisation Radiation (BEIR IV) report (about 40% lower for lifetime exposures). The present data also imply different risks depending on the age at exposure, with relatively higher lifetime risks for exposure at older ages, and relatively lower risks for exposures at younger ages. In conclusion, there was a clear relation between exposure to radon and death from lung cancer. The relative risk of lung cancer due to exposure to radon was not constant in cessation of exposure. The lifetime excess risk of lung cancer implied by these data for 40 years exposure at the current statutory limit of four WLM a year starting at age 20, was about 8% (79 excess deaths per 1000 exposed), assuming average smoking habits among the exposed workers. Control of dust concentrations in the mines has substantially reduced--and may have eliminated--direct mortality from silica related disease.