Excess Lung Cancer Research Articles

Estimation of radon annual effective dose and excess lung cancer risk for the residents of KufrKhal, Jordan

This study aims to measure radon gas concentration, calculate the annual effective dose, and calculate excess lung cancer risk in KufrKhal-Jerash north of Jordan. Radon is a radioactive gas located everywhere and contributes more than 40% of people’s total dose from natural radiation. The Risk concerns have resulted from the increase in mortality due to lung cancer in KufrKhal. About 117 well-calibrated dosimeters were among the study area’s districts (Hill 1, Hill 2, Hill 3, and village center). Each dosimeter consists of a plastic cup with known dimensions and a piece of solid state nuclear track detector (SSNTD) type CR-39 fixed in the inner bottom of the cup. After 90 days, the retrieved detectors were chemically etched, and the track density (tracks.cm−2) was determined. The results showed that the average radon concentrations drastically varied between the districts of KufrKhal (17.1–128.8 Bqm−3). However, the mean radon values in different districts are closely related (64.4–75.5 Bq.m−3). The lowest concentration (17.1 Bqm−3) was found in the Hill 1 district, and the highest value (128.8 Bqm−3) was found in the village center. However, the overall radon concentration in KufrKhal was approximately 69.2 Bqm−3. This value is within the range of the national average level (43.2 – 77.4 Bq.m−3) and way below the national action level (200 Bq.m−3). Furthermore, the corresponding values of the annual effective dose (AED) and the excess lung cancer risk (ELCR) for dwellers in this village were calculated to be 1.8 mSv.y−1 and 0.2%, respectively. These values, according to Jordan’s national regulations are acceptable.

Calculation the Excess Lifetime Lung Cancer Risk and Human Health Risk Assessment by Inhalation of Radon Gas in the Health Centers of Al–Hay City in Wasit, Iraq Using LR-115 Detector

In this paper, the technology used to measure radon concentrations in 8 health centers of Al- Hay city in Wasit, Iraq (December 2019) is one of the types of solid state nuclear track detectors, LR-115. After that, the annual effective dose rate and the excess lifetime cancer risk were calculated for the selected positions in the study area. The detectors were exposed to radon for 45 days, the etched detectors, using an optical microscope, to calculate the track densities, essentially depend on the alpha ray emitted from radon which later on easy converted to radon concentration values. Radon concentration ranges are from (183.47±22.93 to 17.15±2.14) Bq/m3 with a mean of (100.483Bq/m3), which lower than the appropriate radon levels recommended by ICRP "International Commission on Radiological Protection". The readings of "Excess Lifetime Cancer Risk" (ELCR), which ranges from 3.9 ×10-3 to 8.05 ×10-3 with an average value of 0.53% showing that human health is not under risk even it does not develop any lung cancer while human inhale the radon.

Radon levels and dose assessment at the basement workplaces of hospitals in different regions of Taiwan

The basements of large hospitals in Taiwan are usually working areas for image radiometry, radiation therapy, and nuclear medicine, where the radon concentration can be accumulated. This study investigated radon concentrations in the basement working environments of 30 hospitals in different regions with various geology of Taiwan, aiming to explore the relationship between geological conditions and radon concentrations and estimate the radiation dose received by the working staff. Portable MR107+ semiconductor radon detectors calibrated with a radon chamber were used for radon measurement at the hospital basement working areas according to the protocol of MAH-2019 instrument placement recommendations from the US EPA. The excess lung cancer risk (ELCR) as well as the lung cancer cases per million persons (LCC) were further derived from the radiation dose.The basement working areas investigated are located on the first to sixth underground floors of hospitals in Taiwan mainland and islands, Penghu and Kinmen. The 222Rn concentration higher than 100 Bq/m3 was observed at CH-1 (122.1 Bq/m3) in Changhua City and CY-1 (114.7 Bq/m3) in Chiayi City. This is attributed to that the central air conditioning systems of these hospitals were turned off during off-duty hours. The radon concentrations of all hospitals were lower than the action level, 150 Bq/m3, regulated by the US EPA. No significant relationship was found between radon concentration and the geological characteristics of the measured sites. That is, the ventilation of the basement working areas in hospitals is more important than local geological characteristics on indoor radon concentration, and therefore proper ventilation is crucial for reducing radon gas concentration in the hospital basements. Estimated annual effective dose from 222Rn for the hospital staff was higher than 1 mSv/y at YL (1.24 mSv/y), CH-1 (1.64 mSv/y), CY-1 (1.54 mSv/y), CY-2 (1.34 mSv/y), and PH-2 (1.14 mSv/y), and that for the rest sites was <1 mSv/y. The maximum mean ELCR was found to be 0.63% at CH-1, and the related LCC was estimated to be 29.5 per million persons.

Investigations of indoor radon levels and its mapping in the Greater Accra region, Ghana

In this work, the indoor radon concentration and radiation dose risks were studied in dwellings within the Greater Accra region, using CR-39 detectors. The indoor radon concentrations ranged from 36.1 ± 2.7 to 92.0 ± 5.2 Bq m−3 with an annual average of 50.8 ± 3.4 Bq m−3. The annual mean effective dose was estimated as 1.3 mSv year−1. Excess lifetime cancer risk and lung cancer cases were assessed with 5% annual lung cancer deaths due to radon was realized. Indoor radon maps created with ArcGIS software over a 5 × 5 km2 grid showed radon prone areas in the region.

Public Exposure to Natural Radiation and the Associated Increased Risk of Lung Cancer in the Betare-Oya Gold Mining Areas, Eastern Cameroon

Background: This study aims to reevaluate natural radiation exposure, following up on our previous study conducted in 2019, and to assess the associated risk of lung cancer to the public residing in the gold mining areas of Betare-Oya, east Cameroon, and its vicinity.Materials and Methods: Gamma-ray spectra collected using a 7.62 cm×7.62 cm in NaI(Tl) scintillation spectrometer during a car-borne survey, &lt;i&gt;in situ&lt;/i&gt; measurements and laboratory measurements performed in previous studies were used to determine the outdoor absorbed dose rate in air to evaluate the annual external dose inhaled by the public. For determining internal exposure, radon gas concentrations were measured and used to estimate the inhalation dose while considering the inhalation of radon and its decay products.Results and Discussion: The mean value of the laboratory-measured outdoor gamma dose rate was 47 nGy/hr, which agrees with our previous results (44 nGy/hr) recorded through direct measurements (in situ and car-borne survey). The resulting annual external dose (0.29±0.09 mSv/yr) obtained is similar to that of the previous study (0.33±0.03 mSv/yr). The total inhalation dose resulting from radon isotopes and their decay products ranged between 1.96 and 9.63 mSv/yr with an arithmetic mean of 3.95±1.65 mSv/yr. The resulting excess lung cancer risk was estimated; it ranged from 62 to 216 excess deaths per million persons per year (MPY), 81 to 243 excess deaths per MPY, or 135 excess deaths per MPY, based on whether risk factors reported by the U.S. Environmental Protection Agency, United Nations Scientific Committee on the effects of Atomic Radiation, or International Commission on Radiological Protection were used, respectively. These values are more than double the world average values reported by the same agencies.Conclusion: There is an elevated level of risk of lung cancer from indoor radon in locations close to the Betare-Oya gold mining region in east Cameroon. Therefore, educating the public on the harmful effects of radon exposure and considering some remedial actions for protection against radon and its progenies is necessary.

Quantitative assessment of mesothelioma and lung cancer risk based on Phase Contrast Microscopy (PCM) estimates of fibre exposure: an update of 2000 asbestos cohort data

An earlier meta-analysis of mortality studies of asbestos-exposed worker populations, quantified excess mesothelioma and lung cancer risks in relation to cumulative exposure to the three main commercial asbestos types. The aim of this paper was to update these analyses incorporating new data based on increased follow-up of studies previously included, as well as studies of worker populations exposed predominantly to single fibre types published since the original analysis.Mesothelioma as a percentage of expected mortality due to all causes of death, percentage excess lung cancer and mean cumulative exposure were abstracted from available mortality studies of workers exposed predominantly to single asbestos types. Average excess mesothelioma and lung cancer per unit of cumulative exposure were summarised for groupings of studies by fibre type; models for pleural and peritoneal mesothelioma risk and lung cancer risk in terms of cumulative exposure for the different fibre types were fitted using Poisson regression.The average mesothelioma risks (per cent of total expected mortality) per unit cumulative exposure (f/cc.yr), RM, were 0.51 for crocidolite, 0.12 for amosite, and 0.03 for the Libby mixed amphiboles cohort. Significant heterogeneity was present for cohorts classed as chrysotile, with RM values of 0.01 for chrysotile textiles cohorts and 0.0011 for other chrysotile-exposed cohorts. Average percentage excess lung cancer risks per unit cumulative exposure, RL, were 4.3 for crocidolite and amosite combined, 0.82 for Libby. Very significant heterogeneity was present for chrysotile-exposed cohorts with RL values spanning two orders of magnitude from 0.053 for the Balangero mine to 4.8 for the South Carolina textiles cohort. Best fitting models suggest a non-linear exposure-response in which the peritoneal mesothelioma risk is proportional to approximately the square of cumulative exposure. Pleural mesothelioma and lung cancer risk were proportion to powers of cumulative exposure slightly less than one and slightly higher than one respectively.

Comparative study of radon sources and associated health risk in four underground uranium mines.

This paper presents a comparative study of the quantitative estimation of 222Rn and its health risk from various sources in four underground uranium mines. 222Rn exhalation rates from uranium-bearing rocks and backfill materials were estimated by calculating the 222Rn concentration accumulated in an enclosed chamber into which radon was exhaled. This comparative study indicates a more significant effect of porosity on the exhalation rates. Dissolved 222Rn in mine water was estimated using scintillation cell and bubbler kit. The discrepancy in 222Rn concentration in the mines might be attributed to the variation in geological features, ore grade, and porosity. This study revealed that the maximum radon exposure was produced from the backfill mill tailings, followed by uranium ore and mine water in the mines. The radon dose values in the individual mines remained under the safe dose limit of 20mSvyear-1. The excess lifetime cancer risk (ELCR) and 222Rn-induced lung cancer cases (RnLCC) per million persons per year were also estimated.

Workers in Australian prebake aluminium smelters: update on risk of mortality and cancer incidence in the Healthwise cohort

ObjectivesTo investigate mortality and the rates of incident cancer among a cohort of aluminium industry workers.MethodsAmong 4507 male employees who worked in either of two Australian prebake smelters for at...

Facteurs de risques professionnels des cancers broncho-pulmonaires, données épidémiologiques, repérage des expositions et enjeux médico-sociaux : l’amiante comme paradigme

Lung cancer is the most common occupational-related cancer location, although tobacco smoking is its primary risk factor. Many occupational carcinogens or exposure situations are identified as definite carcinogens with an excess of lung cancers in humans by the International Agency for Research on Cancer. A recent study reported a 14.6% attributable risk fraction to work for this cancer site in France, which would amount to more than 5,900 annual cases. Asbestos is the most common occupational risk factor involved in lung cancer, with an estimated 9.3% attributable fraction in humans, or 2,715 cases in France. However, at the same time, less than 1100 cases of lung cancer per year are compensated annually as an occupational disease under the general social insurance system. It is therefore essential to identify the nuisances and occupational exposure situations involved in the lung cancer, in order to put in place effective prevention strategies and close monitoring of potentially exposed employees. Finally, for a patient presenting with lung cancer, the identification of a relationship with his professional activity must be systematically sought, in order to allow him to take possible medicallegal steps for compensation of his disease, or additional request to the Compensation Fund for Asbestos Victims (FIVA) and to request a possible early termination of activity for asbestos exposure situations.1877-1203/© 2022 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Why are Silica Dust Exposures and Silica-Related Health Effects Still a Global Concern?

Background and aim Epidemiology studies of workers exposed to silica dust demonstrate that crystalline SiO2 is a multipotential hazard. Research among construction workers, miners, ceramic and brick workers, countertops workers, and sandblasters where respirable silica dust levels has been measured has demonstrated excess risk for silicosis, cor pulmopale, silica-tuberculosis (SiTB), several chronic respiratory conditions, coal workers pneumoconiosis (CWP), several auto-immune diseases, and cancers of the lung and gastro-intestinal tract. Methods Despite knowledge of these links over the past decades, occupational and environmental health professionals have not been able to address three new silica-related health issues. They are silicosis and CWP among US coal miners, severe silicosis and auto-immune ailments among countertop workers; and ongoing risk for SiTB among Africa miners. The author examined the literature for other novel silica-related health risks. Results Current workers and their managers seem to not have sufficient awareness of the occupational hazards of silica dust. There are new silica dust concerns including fracking sand, railroad ballast, and dust control in countertop machining. There are new cancer links with silica, including women and nonsmokers with excess lung cancer; excess lung cancer among patients with CWP; children’s dust exposure in small-scale gold mining; and excess lung diseases and pulmonary cancer among railroad workers. There is need for research on improved silica sampling techniques and protective gear. Pathologists should explore whether silicosis leads to differences in cell characteristics that produce silica-linked lung cancers compared to ‘garden variety’ malignancies. Conclusion Despite promises that global silica problems were controlled, that seems to be countered by excesses of CWP and SiTB that still bedevil the occupational medicine and public health communities. We need more worker education, prevention or regulatory policy, and basic silica biology and pathology to effectively intervene. Keywords Silica health effects, future prevention efforts; improved sampling methods

Health and economic gain attributable to the introduction of the World Health Organization's drinking water standard on arsenic level in Hungary: A nationwide retrospective study on cancer occurrence and ischemic heart disease mortality

The World Health Organization (WHO) estimates that 140 million individuals are at risk from consumption of drinking water containing arsenic at concentrations above the WHO guideline value of 10 μg/l. Arsenic mitigation is considered to be the most effective way to prevent arsenic related diseases. After joining the European Union, Hungary implemented a Drinking Water Quality Improvement Programme (DWQIP) to reduce levels of arsenic in drinking water below the WHO guideline value. But what impact did this have on health? We estimated the change in lifetime excess skin, lung, and bladder cancer risks and mortality from ischaemic heart disease (IHD) associated with chronic arsenic intake among those exposed before (2004–2007) and after (2014–2017) the implementation of DWQIP. A population-based risk assessment approach was used to assess lifetime excess cancer risk applying two scenarios for lung and bladder cancers. The economic benefits of the DWQIP were estimated by the combination of cost of illness and value per statistical life methods. Compared to the period before the DWQIP, its implementation was associated with a significant reduction in arsenic in drinking water [median: 3.0 μg/l interquartile range (IQR): 1.5–12.0 μg/l to median: 2.15 μg/l IQR: 1.0–5.79 μg/l]. The two scenarios were estimated to be associated with 225.2 and 35.9 fewer cancer cases each year. The number of annually prevented IHD deaths was estimated to be 88.9. It was estimated that the benefits of the DWQIP will outweigh its costs. We conclude that reducing arsenic levels in drinking water to 10.0 μg/l resulted in significant health and economic benefits. Our study goes beyond the existing research, offering both new insights into the impact of arsenic mitigation and providing a methodological template for similar studies in the many parts of the world that have yet to reduce arsenic exposure.

Sex disparity of lung cancer risk in non-smokers: a multicenter population-based prospective study based on China National Lung Cancer Screening Program.

Background:Non-smokers account for a large proportion of lung cancer patients, especially in Asia, but the attention paid to them is limited compared with smokers. In non-smokers, males display a risk for lung cancer incidence distinct from the females—even after excluding the influence of smoking; but the knowledge regarding the factors causing the difference is sparse. Based on a large multicenter prospective cancer screening cohort in China, we aimed to elucidate the interpretable sex differences caused by known factors and provide clues for primary and secondary prevention.Methods:Risk factors including demographic characteristics, lifestyle factors, family history of cancer, and baseline comorbidity were obtained from 796,283 Chinese non-smoking participants by the baseline risk assessment completed in 2013 to 2018. Cox regression analysis was performed to assess the sex difference in the risk of lung cancer, and the hazard ratios (HRs) that were adjusted for different known factors were calculated and compared to determine the proportion of excess risk and to explain the existing risk factors.Results:With a median follow-up of 4.80 years, 3351 subjects who were diagnosed with lung cancer were selected in the analysis. The lung cancer risk of males was significantly higher than that of females; the HRs in all male non-smokers were 1.29 (95% confidence interval [CI]: 1.20–1.38) after adjusting for the age and 1.38 (95% CI: 1.28–1.50) after adjusting for all factors, which suggested that known factors could not explain the sex difference in the risk of lung cancer in non-smokers. Known factors were 7% (|1.29–1.38|/1.29) more harmful in women than in men. For adenocarcinoma, women showed excess risk higher than men, contrary to squamous cell carcinoma; after adjusting for all factors, 47% ([1.30–1.16]/[1.30–1]) and 4% ([7.02–6.75]/[7.02–1])) of the excess risk was explainable in adenocarcinoma and squamous cell carcinoma. The main causes of gender differences in lung cancer risk were lifestyle factors, baseline comorbidity, and family history.Conclusions:Significant gender differences in the risk of lung cancer were discovered in China non-smokers. Existing risk factors did not explain the excess lung cancer risk of all non-smoking men, and the internal causes for the excess risk still need to be explored; most known risk factors were more harmful to non-smoking women; further exploring the causes of the sex difference would help to improve the prevention and screening programs and protect the non-smoking males from lung cancers.

Estimating Radon Excess Lung Cancer at the Babylon Cement Plant in Iraq

Abstract In this work, radon excess lung cancer (ELC) was estimated for 14 soil samples from the Babylon cement plant in Iraq. A CR-39 nuclear track detector was used to measure uranium and radon (222Rn) concentrations in the soil samples. The uranium concentration varied from 0.008 to 0.05 ppm, with a mean value of 0.025 ± 0.013 ppm. The radon concentration was found to be between 31 and 92 Bq/m3, with a mean value of 56.72 and a standard division of 17.29. The radon ELC per million persons per year has a mean value of 863 (463.81–12,082.8) and a standard division of 261.65. The annual effective dose, E (mSv/y), ranged from 0.77 to 2.32, with a mean value of 1.44 and a standard division of 0.44.

Cancer Risk and Diesel Exhaust Exposure Among Railroad Workers

Inhalation exposure to diesel exhaust in the railroad work environment causes significant and quantifiable cancer risks to many railroad workers. Diesel exhaust has been identified as a known human carcinogen by the International Agency for Research on Cancer (“IARC”) and as a potential carcinogen by the United States Environmental Protection Agency (“USEPA”), the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (“OEHHA”), and the National Institute for Occupational Safety & Health (“NIOSH”). Peer-reviewed literature defines the ambient air concentrations of diesel exhaust for several railroad occupations as being above environmental background levels. This study uses diesel exhaust concentrations in the railroad work environment in conjunction with the USEPA’s Integrated Risk Information System (“IRIS”) risk assessment methodology to quantify the cancer risk posed to railroad workers due to occupational inhalation exposure to diesel exhaust. NIOSH Bulletin 68 (2017) states that there is “no known safe level” of exposure to carcinogens and recommends an evaluation of the USEPA’s IRIS guidance to evaluate quantitative risk assessment of human exposure to occupational carcinogens. This is the first study to utilize USEPA methodology to calculate the excess lung cancer risk caused by railroad workers’ cumulative exposure to diesel exhaust.

Long-term spatiotemporal variation and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons (PAHs) in the Yangtze River Delta, China.

The Yangtze River Delta (YRD), which is the most developed region in China, suffers from atmospheric polycyclic aromatic hydrocarbons (PAH) pollution. However, the long-term spatiotemporal variation of atmospheric PAHs and the lung cancer risk caused by PAH exposure in the YRD remain unclear. Herein, we simulated the daily atmospheric concentration of benzo[a]pyrene (BaP, the most carcinogenic PAH) from 2001 to 2016 using an atmospheric transport model. During this period, the atmospheric BaP concentration showed a general trend of first increasing and then decreasing (average BaP concentration = 0.50 ± 0.12ng/m3) and was highest in 2005 (0.72ng/m3). Moreover, the BaP concentration in Jiangsu and Shanghai was 5.17- and 4.98-fold higher than that in Zhejiang. BaP pollution was severe in Jiangsu during the winter. The average area proportion of BaP exceeding the national standard in winter in Jiangsu was 69.09%. The population-weighted incremental lifetime cancer risk from 2001 to 2016 ranged 6.67 × 10-6-1.50 × 10-5, and the excess lung cancer cases ranged 1054-2130. Compared with 2005, excess lung cancer cases in the YRD decreased by 49.49% in 2016. Reducing BaP pollution in winter in Jiangsu is crucial for reducing lung cancer risk in the YRD.

The incidence of the adult population living in the "uranium legacy" area in conditions of radon exposure

Introduction. The purpose of the study is to assess the health status of the adult population of the Lermontov city, Stavropol Territory, living in the “uranium legacy” area in conditions of increased exposure to radon in residential premises has been investigated. Materials and methods. The material of the study was the medical statistics data for the period 2009-2018 reported by Clinical Hospital No. 101 under FMBA of Russia, presented in forms No. 7 (information on malignant diseases) and No. 12 (information on the number of diseases in adults). The frequency, structure and dynamics of primary morbidity and incidence of malignant neoplasms were evaluated. Results. During the period under review, a high primary incidence in the adult population was revealed (average: 748.2 ± 111.4 per 1000 persons) to increase and significantly exceeded the same indicator in the Stavropol Territory (390.3 ± 20.3 per 1000 persons) The incidence of four classes of diseases: diseases of the musculoskeletal system and connective tissue, diseases of the genitourinary system, diseases of the skin and subcutaneous tissue, diseases of the eye and adnexa was significantly higher than the regional average value. The incidence of respiratory diseases (lungs - a critical organ to the action of radon) did not significantly differ from the average regional indicators. On the contrary, the incidence of malignant neoplasms decreased (330.6 ± 1.1 per 100.0 persons) and on average approached that in the region (320.5 ± 11.4 per 100.0 persons). At the same time, the incidence of lung cancers was significantly lower than the regional average (22.6 ± 3.0 and 33.5 ± 0.3 per 100.0 persons, respectively). Limitations. The study is limited to studying the state of incidence (primary, cancer) of Lermontov adult population. The estimation of the relative number of excess lung cancers is based on the expert assessment of the ICRP of the corresponding coefficient. Conclusion. According to medical statistics for 2009-2018, the population of Lermontov had a relatively low incidence of malignant neoplasms, including lung cancers, of which, according to theoretical estimates, no more than 15-20% of cases can be conditionally associated with radon exposure. The revealed relatively high primary incidence of the adult population seems to be associated with the adverse impact on health of numerous factors of the human environment. Presumably, this situation also reflects the availability of quality medical care for the population.

Indoor radon measurement in buildings of a university campus in central Iran and estimation of its effective dose and health risk assessment.

Indoor radon is a serious health concern and contributes about 10% of deaths from lung cancer in the USA and Europe. In this study, radon and thoron levels of 20 multi-floor buildings on the campus of Isfahan University of Medical Sciences were measured in cold and hot seasons of a year. SARAD- RTM1688 radon and thoron monitor was used for measurement. The annual effective dose of radon exposure was also estimated for residences on the campus. The results showed that radon concentration was below the WHO guideline (100 Bq m- 3) in most of the buildings. The ranges of radon were from 3 ± 10% to 322 ± 15% Bq m- 3 in winter and from below the detectable level to 145 ± 8% Bq m- 3 in summer. Mostly, the radon concentration in the basement or ground floors was higher than upper floors, however, exceptions were observed in some locations. For thoron, no special trends were observed, and in the majority of buildings, its concentration was below the detectable level. However, in a few locations besides radon, thoron was also measured at a high level during both seasons. The average annual effective dose via radon exposure was estimated to be 0.261 ± 0.339 mSv y- 1. The mean excess lung cancer risk (ELCR) was estimated to be 0.10%. It was concluded that indoor air ventilation, buildings' flooring and construction materials, along with the geological structure of the ground could be the factors influencing the radon concentration inside the buildings. Thus, some applicable radon prevention and mitigation techniques were suggested.

Assessment of excess lifetime cancer risk and risk of lung cancer due to exposure to radon in a middle eastern city in Iran

ObjectiveTo assess the excess lifetime cancer risk and lung cancer risk due to exposure to 222Rn at homes, stone cutting and processing plants, and stone mines. Methods222Rn concentration was measured in 74 sample sites. Sampling was conducted using Alpha Track, comprising CR-39 polymer film. The detectors were placed at the height of 1.00–1.50 m from the floor and away from windows and sunlight per the US. EPA guidelines. The detectors were retrieved after being exposed to 222Rn for the period of three months and then etched in a 6.25 mol/L NaOH solution at 90 °C for 4 h. The results were used to assess the excess lifetime cancer risk (ELCR) and lung cancer risk (LCR). ResultsThe findings showed that the ELCR at homes, stone cutting and processing plants, and stone mines for the mean levels of 222Rn were 0.49%, 0.15%, and 0.15%, respectively. The ELCR values for all sampling sites were lower than the U.S. EPA action level. The number of lung cancer cases in the Neyriz due to the effective dose received by residents for the mean, maximum, and 95th percentile was estimated to be 1.6, 3.6, and 3.1 per year, respectively. The number of lung cancer cases per 106 population due to exposure to mean concentration for stone cutting and processing plants was 10.53, 15.79, and 14.49, respectively. These values for stone mines were 10.39, 26.76, and 18.87, respectively. The results have shown that LCR values were below the range recommended by ICRP. ConclusionsOverall, the ELCR, because of long-term exposure to 222Rn and its progeny levels, does not pose a significant threat to residents and workers. The LCR associated with radon exposure was low in three sampling sites that could be considered safe for both residents and workers.

Estimation of radon excess lung cancer near some dumpsites in, Lagos, Nigeria

Generally, in Nigeria dumpsites are open and elevate the pollution by increasing the total environment contamination level. This affects not only the site of dumpsites but also the surrounding buildings and area. In the present work, indoor radon activity concentration is tested inside some buildings in the vicinity of dumpsites in Lagos, Nigeria. A passive technique with CR-39 detectors is used. Different buildings around different eight dumpsites were chosen. Radon concentration had ranged from 16.00 ± 3 to 931.00 ± 186 Bqm−3 in the dumpsites. With Mean concentrations range from 120 ± 24 at OKE-ODO to 334 ± 67, at Solus-4 respectively. The present results explain that 63% of the radon activity concentration in indoor air around the selected dumpsites at Lagos city in Nigeria is below the allowed limit from ICRP 200 Bq m-3 while 37% is more than this limit. Based on the measured radon concentration, the annual effective dose and cancer risk are evaluated. The range of ELC is from 242 to 14086 with mean value 3114 ± 1111.

Living alone as a risk factor for cancer incidence, case-fatality and all-cause mortality: A nationwide registry study

Lack of social contacts has been associated with an increased risk of cancer mortality, but it is not known whether living alone increases the risk of cancer incidence or case fatality. We examined the association between living alone with cancer incidence, case-fatality and all-cause mortality in eight most common cancers. All patients with their first cancer diagnosis in 2000–2017 were identified from the nationwide Finnish Cancer Registry. Information on living arrangements was derived from Statistics Finland. The incidence analyses were conducted using Poisson regression. The total Finnish population served as the population at risk. Fine-Gray model was used to estimate case-fatality and Cox proportional regression model all-cause mortality. In men, we found an association between history of living alone and excess lung cancer incidence but living alone seemed to be associated with lower incidence of prostate cancer and skin melanoma. In women, living alone was more consistently associated with higher incidence of all studied cancers. Cancer patients living alone had an 11%–80% statistically significantly increased case-fatality and all-cause mortality in all studied cancers in men and in breast, colorectal and lung cancer in women. Living alone is consistently associated with increased cancer incidence risk in women but only in some cancers in men. Both men and women living alone had an increased risk of all-cause mortality after cancer diagnosis.