Residential radon and lung cancer: a cohort study in Galicia, Spain

Lung cancer risk and exposure to air pollution: a multicenter North China case-control study involving 14604 subjects

BACKGROUND

For North Chinese lung cancer patients, there is limited study on the distribution of air pollution and smoking related features based on analyses of large-scale, high-quality population datasets. The aim of the study was to fully analyze risk factors for 14604 Subjects.

METHODS

Participants and controls were recruited in 11 cities of North China. Participants' basic information (sex, age, marital status, occupation, height, and weight), blood type, smoking history, alcohol consumption, history of lung-related diseases and family history of cancer were collected. PM2.5 concentration data for each year in each city of the study area from 2005 to 2018 were extracted based on geocoding of each person's residential address at the time of diagnosis. Demographic variables and risk factors were compared between cases and matched controls using a univariate conditional logistic regression model. Multivariate conditional logistic regression models were applied to estimate the odds ratio (OR) and 95% confidence interval (CI) for risk factors in univariate analysis. The nomogram model and the calibration curve were developed to predict lung cancer probability for the probability of lung cancer.

RESULTS

There was a total of 14604 subjects, comprising 7124 lung cancer cases and 7480 healthy controls included in the study. Marital status of unmarried persons, people with a history of lung-related disease, corporate personnel and production /service personnel were protective factors for lung cancer. People younger than 50 years old, people who were smoking and quit smoking, people who had been drinking consistently, people with family history of cancer and PM2.5 exposure were proven to be a risk factor for lung cancer. The risk of lung cancer varied with sex, smoking status and air pollution. Consistent alcohol consumption, persistent smoking and smoking quit were risk factors for lung cancer in men. By smoking status, male was risk factor for lung cancer in never smokers. Consistent alcohol consumption added risk for lung cancer in never smokers. The combined effects of PM2.5 pollution exposure and ever smoking aggravated the incidence of lung cancer. According to air pollution, lung cancer risk factors are completely different in lightly and heavily polluted areas. In lightly polluted areas, a history of lung-related disease was a risk factor for lung cancer. In heavily polluted areas, male, consistent alcohol consumption, a family history of cancer, ever smokers and smoking quit were all risk factors for lung cancer. A nomogram was plotted and the results showed that PM2.5 was the main factor affecting the occurrence of lung cancer.

CONCLUSIONS

The large-scale accurate analysis of multiple risk factors in different air quality environments and various populations, provide clear directions and guidance for lung cancer prevention and precise treatment.

Ecological level analysis of primary lung tumors in dogs and cats and environmental radon activity

Background

Epidemiologic studies suggest residential radon exposure might increase the risk of primary lung cancer in people, but these studies are limited by subject mobility. This limitation might be overcome by evaluating the association in pets.

Hypothesis

Primary pulmonary neoplasia (PPN) rate is higher in dogs and cats residing in counties with a high radon exposure risk (Environmental Protection Agency [EPA] zone 1) compared to zones 2 (moderate radon exposure risk) and 3 (low radon exposure risk).

Animals

Six hundred ninety client‐owned dogs and 205 client‐owned cats with PPN.

Methods

Retrospective review of medical records at 10 veterinary colleges identified dogs and cats diagnosed with PPN between 2010 and 2015. Each patient's radon exposure was determined by matching the patient's zip code with published county radon exposure risk. County level PPN rates were calculated using the average annual county cat and dog populations. The PPN counts per 100 000 dog/cat years at risk (PPN rates) were compared across radon zones for each species.

Results

The PPN rate ratio in counties in high radon zone (1) was approximately 2‐fold higher than in counties in lower radon zones for dogs (rate ratio zone 1 to 2, 2.49; 95% confidence interval [CI], 1.56‐4.00; rate ratio zone 1 to 3, 2.29; 95% CI, 1.46‐3.59) and cats (rate ratio zone 1 to 2, 2.13; 95% CI, 0.95‐4.79; zone 1 to 3, 1.81; 95% CI, 0.9‐3.61).

Conclusions and Clinical Importance

Exposure to household radon might play a role in development of PPN in dogs and cats.

Residential Radon in Central and South America: A Systematic Review

Radon gas is a pulmonary carcinogen and the second leading cause of lung cancer after smoking. There are many countries that have not implemented measures to reduce the risk it poses to the general population. The aim of this study was to locate available evidence on exposure to residential radon and the regulations to monitor and control this across Central and South America, by conducting a review of the scientific literature and government documents in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This review included 31 studies which had taken measurements of radon in these countries. While Brazil, Argentina, and Peru have undertaken most research, no country in Central and South America has a national map of exposure to residential radon. The prevalence of exposure to radon was uneven, both among the different countries and within individual countries. No country has regulations to prevent the entry of radon into homes, and nine countries have not set maximum permissible concentrations for residential radon. There is a limited number of studies in South and Central America, with a limited spatial coverage, and there is a need to improve knowledge on exposure to residential radon and its effects, and for governments to take the necessary actions to introduce preventive measures in their statutory regulations.

Estimates of the Lung Cancer Cases Attributable to Radon in Municipalities of Two Apulia Provinces (Italy) and Assessment of Main Exposure Determinants

Indoor radon exposure is responsible for increased incidence of lung cancer in communities. Building construction characteristics, materials, and environmental determinants are associated with increased radon concentration at specific sites. In this study, routine data related to radon measurements available from the Apulia (Italy) Regional Environmental Protection Agency (ARPA) were combined with building and ground characteristics data. An algorithm was created based on the experience of miners and it was able to produce estimates of lung cancer cases attributable to radon in different municipalities with the combined data. In the province of Lecce, the sites with a higher risk of lung cancer are Campi Salentina and Minervino, with 1.18 WLM (working level months) and 1.38 WLM, respectively, corresponding to lung cancer incidence rates of 3.34 and 3.89 per 10 × 10³ inhabitants. The sites in the province of Bari with higher risks of lung cancer are Gravina di Puglia and Locorotondo, measuring 1.89 WLM and 1.22 WLM, respectively, which correspond to an incidence rate of lung cancer of 5.36 and 3.44 per 10 × 10³ inhabitants. The main determinants of radon exposure are whether the buildings were built between 1999 and 2001, were one-room buildings with porous masonry, and were built on soil consisting of pelvis, clayey sand, gravel and conglomerates, calcarenites, and permeable lithotypes.