Is environmental radon gas associated with the incidence of neurodegenerative conditions? A retrospective study of multiple sclerosis in radon affected areas in England and Wales

To test whether an association exists between radon gas concentration in the home and increased multiple sclerosis (MS) incidence, a retrospective study was undertaken of MS incidence in known areas of raised domestic radon concentration in England and Wales, using The Health Improvement Network (THIN) clinical research database.The study population comprised 20,140,498 person-years of clinical monitoring (males: 10,056,628: 49.93%; females: 10,083,870: 50.07%), representing a mean annual population of 2.5 million individuals. To allow for the possible latency of MS initiation following exposure, data extraction was limited to patients with at least five years registration history with the same GP practice before first diagnosis. Patient records were allocated to one of nine radon concentration bands depending on the average radon level in their postcode sector.MS incidence was analysed by searching for patients with first MS diagnosis over the eight calendar years 2005-2012 inclusive. 1512 new MS cases were diagnosed, 1070 females, 442 males, equivalent to raw incidence rates of 7.51, 10.61 and 4.40 per 105person-years respectively, comparable to previously reported results. Of these new cases, 115 could be allocated to one of the radon bands representing high radon areas.Standardising to the UK 2010 population, excess relative risk (ERR) figures for MS were calculated for each radon band. Linear regression of ERR against mean band radon concentration shows a positive gradient of 0.22 per 100 Bq·m-3(R2= 0.25, p = 0.0961) when forced through the origin to represent a linear-no-threshold response. The null hypothesis falls inside the 95% confidence interval for the linear fit and therefore this fit is not statistically significant. We conclude that, despite THIN sampling around 5% of the population, insufficient data was available to confirm or refute the hypothesised association between MS incidence and radon concentration

Sorrentina peninsula: Geographical distribution of the indoor radon concentrations in dwellings—gini index application

The radon isotope (222Rn, half-life 3.8 days) is a radioactive byproduct of the238U decay chain. Because radon is the second biggest cause of lung cancer after smoking, dense maps of indoor radon concentration are required to implement effective locally based risk reduction strategies. In this regard, we present an innovative method for the construction of interpolated maps (kriging) based on the Gini index computation to characterize the distribution of Rn concentration. The Gini coefficient variogram has been shown to be an effective predictor of radon concentration inhomogeneity. It allows for a better constraint of the critical distance below which the radon geological source can be considered uniform, at least for the investigated length scales of variability; it also better distinguishes fluctuations due to environmental predisposing factors from those due to random spatially uncorrelated noise. This method has been shown to be effective in finding larger-scale geographical connections that can subsequently be connected to geological characteristics. It was tested using real dataset derived from indoor radon measurements conducted in the Sorrentina Peninsula in Campania, Italy. The measurement was carried out in different residences using passive detectors (CR-39) for two consecutive semesters, beginning in September– November 2019 and ending in September–November 2020, to estimate the yearly mean radon concentration. The measurements and analysis were conducted in accordance with the quality control plan. Radon concentrations ranged from 25 to 722 Bq/m3 before being normalized to ground level, and from 23 to 933 Bq/m3 after being normalized, with a geometric mean of 120 Bq/m3 and a geometric standard deviation of 1.35 before data normalization, and 139 Bq/m3 and a geometric standard deviation of 1.36 after data normalization. Approximately 13% of the tests conducted exceeded the 300 Bq/m3 reference level set by Italian Legislative Decree 101/2020. The data show that the municipalities under investigation had no influence on indoor radon levels. The geology of the monitored location is interesting, and because soil is the primary source of Rn, risk assessment and mitigation for radon exposure cannot be undertaken without first analyzing the local geology. This research examines the spatial link among radon readings using the mapping based on the Gini method (kriging)

Evaluation of Radon Exposure Risk and Lung Cancer Incidence/Mortality in South-Eastern Italy

Introduction: Radon and its decay products may cause substantial health damage after long-term exposure. The aim of the study was to perform a spatial analysis of radon concentration in the Salento peninsula, province of Lecce (South-eastern Italy) in order to better characterize possible risk for human health, with specific focus on lung cancer.Methods: Based on previous radon monitoring campaigns carried out in 2006 on behalf of the Local Health Authority (ASL Lecce) involving 419 schools and through the application of kriging estimation method, a radon risk map was obtained for the province of Lecce, in order to determine if areas with higher radon concentrations were overlapping with those characterized by the highest pulmonary cancer incidence and mortality rates.Results: According to our data, areas at higher radon concentrations seem to overlap with those characterized by the highest pulmonary cancer mortality and incidence rates, thus indicating that human exposure to radon could possibly enhance other individual or environmental pro-carcinogenic risk factors (i.e. cigarette smoking, air pollution and other exposures).Conclusions: The radon risk should be further assessed in the evaluation of the causes resulting in higher mortality and incidence rates for pulmonary cancer in Salento area vs Italian average national data. For these reasons, ASL Lecce in cooperation with ARPA Puglia and CNR-IFC has included the monitoring of individual indoor radon concentrations in the protocol of PROTOS case-control Study, aimed at investigating the role of different personal and environmental risk factors for lung cancer in Salento

MODELLING OF GEOGENIC RADON IN SARDINIA AND HEALTH RISK ASSESSMENT

Enhanced level of radon in indoor environments such as homes, schools, public buildings and workplaces is considered an important health issue. Provided that radon is responsible for about 3–14 percent of all lung cancers, governments and inter-governmental institutions have issued several rules in the field of radioprotection of people from exposure to radon and its progenies. As one of the main preventive measures in Europe, the 2013/59/EURATOM BSS Directive requires the member states countries to prepare an action plan to address the radon potential source and identify Radon Prone Areas (RPAs), where the radon concentration is expected to exceed the national threshold level (as annual average of 300 Bq m-3 for both residential and workplaces). Following this directive, the work to be discussed here focuses on the preparation of a radon potential map of Sardinia according to the “Vast Area” approach and based on the use of literature derived geogenic data (e.g. lithological and geological types, U and Ra content, soil-gas radon, permeability and tectonics). As one of the main results of this thesis work, a predictive Geogenic Radon Potential (GRP) map expressing the radon potentials in ordinal categories was developed. The produced GRP map has merit because 1) it doesn't depend on the anthropogenic factors (e.g. building material, ventilation rate and living habits); 2) it can be used for the estimation of the radon hazard of both existing buildings and future construction sites, thus for the land-use planning. Complementary field and laboratory-based experiments were conducted to examine the predictive power of the proposed GRP map. Through the validation tests, we tried to answer three main questions; 1) considering the effect of radon anthropogenic factors, is it possible to use the GRP levels to estimate the indoor radon concentration for an area? 2) Do the results of real-time pilot tests in an area identified as RPA correlate with the category of radon potential predicted by the GRP map? And 3) is it possible to use the GRP map to justify the occurrence of enhanced levels of radon in closed spaces? In general, the correlations between examination test results and the predicted radon potential by the GRP map showed that the proposed map can address the major source of indoor radon in Sardinia. Besides, the radon emanation potential and natural radioactivity of the building material, the second major contributor to the indoor radon activity, was also investigated in detail parallel to the GRP mapping. The application of radon is not limited to addressing the health hazard. Radon monitoring coupled with natural radioactivity detection can be used as a tool for radiogenic assessments. This application was investigated in an area that consists of heavy mineral placer deposits in South-Eastern Sardinia. Through this experiment, the natural radioactive characteristics and radon-related behaviors of studied formations were well-distinguished The last year of the Ph.D. programme was carried out at Trinity College of Dublin, where the primary purpose of the study was to evaluate in detail the radon and thoron potential in an area with complex geology. Data obtained from radiometric surveys, geochemical measurements and indoor radon concentrations were used to distinguish radon and thoron release from different geo formations and soil types. To aim this, a set of samples were collected from selected geo types and radon/thoron exhalation rates were estimated through laboratory experiments. As a result, radon and thoron potential maps were developed. In the next step, a detailed investigation of soil gas radon concentrations was considered in a radon priority area identified through the potential maps. As a result of the second investigation, a geostatistical model was built to estimate the GRPs with higher accuracy

Spatial epidemiology of lung-cancer mortality : geographical heterogeneity and risk-factors assessment

PhD ThesisCancer is the leading cause of mortality in Andalucía (southern Spain) for both men and women, and lung cancer is the main cause of cancer mortality for men. Radon-gas exposure is the second most important cause of lung-cancer after tobacco-smoking, which also causes larynx cancer, and Chronic Obstructive Pulmonary Disease (COPD). Radon-gas is a radioactive decay element which originates from radium. Consequently, presence in the soil varies according to lithology (rock composition) which is a surrogate measure for potential radon-gas exposure. Lithology can explain some lung-cancer deaths, but not deaths due to either larynx cancer or COPD. A small-area analysis was implemented for the period 1986-1995. Fully-Bayesian regression analysis was used to assess the association between lithology and the spatial distribution of lung-cancer deaths (25,006 cases). Area-level deprivation, a surrogate measure for tobacco-smoking, was accounted for. The number of deaths due to larynx cancer (3,653 cases) and COPD (5,143 cases) were also modelled for comparison purposes. Computation was accomplished via Markov Chain Monte Carlo methods, using WinBUGS software. The spatial distribution of lung-cancer deaths (but neither larynx cancer, nor COPD) was positively associated with lithology, which is consistent with current epidemiological knowledge. These results remained after adjusting for area-level deprivation. The model used allows for separate estimation of risk due to both lithology (RR = 1.02; 95% Credible Interval (CI) = 1.015 – 1.031) and deprivation (RR = 1.04; 95% CI = 1.033 – 1.048). This lithology score overcomes the difficulties in obtaining actual radon-gas measurements, and can be further improved. The results go some way to explaining the regional variability in lung cancer mortality in Southern Spain.Fellowship granted by the Spanish body Instituto de Salud Carlos III (ref BAE06/90003

2nd International Workshop on the European Atlas of Natural Radiation: Book of Abstracts

On 6-9 November 2017, the JRC hosted the 2nd International Workshop on the European Atlas of Natural Radiation in the town of Verbania, Italy. The main aim of this meeting was to present the status and discuss progress of the European Atlas of Natural Radiation. It also provided a scientific reference frame for EU Member States' authorities to implement their radon action plan under the European Basic Safety Standards Directive. This is the book of abstracts selected for oral presentations at that venue.JRC.G.10-Knowledge for Nuclear Security and Safet

Radon prone areas in Friuli Venezia Giulia: ecological analysis and modelling

2013/2014La tesi descrive il lavoro effettuato e i progressi raggiunti durante i miei tre anni di dottorato, volti allo studio della distribuzione delle concentrazioni di radon in ambienti indoor, nello specifico in abitazioni private del Friuli Venezia Giulia. Il principale obiettivo è stato la definizione geografica delle cosiddette radon prone areas (RPA), ovvero le aree con le più alte probabilità di trovare concentrazioni di radon più elevate. Nonostante ciò, molte analisi supplementari sono state effettuate per migliorare la suddetta definizione e per ampliare il bagaglio di conoscenze riguardante il radon indoor a tutto tondo. Abstract La prima parte della tesi è un'introduzione al corpo principale del testo e introduce il problema ambientale radon al lettore. Abstract Nel capitolo uno sono elencate i principali dettagli sul ^{222}Rn , il più frequente isotopo del suo tipo in natura, e un veloce excursus volto alla descrizione delle sue proprietà fisiche, in particolare i meccanismi di trasposto da e all'interno del suolo (che ne è la principale sorgente). Successivamente, i principali meccanismi di entrata in ambienti chiusi sono evidenziati con esempi dei modelli matematici che li descrivono. Abstract Il secondo capitolo è invece la presentazione del problema sanitario posto dal radon. Il suo processo di decadimento e i suoi “figli” sono presentati come principali contributori alla dose assorbita media di radiazione nella popolazione mondiale e il più comunemente accettato modello matematico di impatto viene descritto. Alcuni passaggi sono poi dedicati agli aspetti legislativi, con la legislazione corrente e i passaggi che hanno portato alla attuale situazione. Abstract Il terzo capitolo è la descrizione delle campagne di misura che hanno prodotto i dati sui quali ho lavorato. Le campagne sono due, la prima (RPA2006) si è conclusa otto anni fa, ma i dati non erano ancora stati completamente analizzati. Il mio lavoro principale nei primi due anni di phd è stato dedicato all'analisi dei suddetti, con le tecniche statistiche più raffinate tra quelle applicate in questo campo. La seconda campagna (RPA2014) è terminata nel Novembre del 2014 ed è stata curata completamente da me (con l'ovvio aiuto del personale ARPA), sia per quanto riguarda la logistica, sia per l'aspetto analitico. Abstract La seconda parte della tesi contiene analisi originali sui dati e può essere considerata una collezione di analisi esplorative, precedenti all'uso di tecniche e modelli di interpolazione. Abstract Il capitolo quattro può esser visto come una introduzione alle tecniche esplorative, perché introduce le principali ipotesi usate nella statistica spaziale non parametrica. A parte un piccolo accenno alla fine del capitolo, nessuna definizione richiede la conoscenza delle proprietà fisiche o statistiche del radon. Contiene già le prime mappe non parametriche, come esempi di applicazione delle ipotesi scritte nel testo. In alcune analoghe campagne effettuate in altre zone del pianeta, tali mappe sono spesso considerate sufficienti per la definizione delle RPA. Abstract Il quinto capitolo introduce, invece, le caratteristiche statistiche del radon, descrivendo le prime peculiarità che ho riconosciuto nei dati e che ho cercato di trattare. Nello specifico, gli argomenti qui affrontati sono la quasi-lognormalità, e conseguentemente la deviazione da essa, e l'eventuale multigaussianità. Il clustering (naturale e preferenziale) ha occupato una grossa parte del tempo speso in questi tre anni, di conseguenza alcuni algoritmi di analisi adottati per verificarne le proprietà sono descritti e esemplificati. Abstract Il capitolo sei spiega le analisi, usualmente univariate, che ho condotto con tutte le variabili covariate possibilmente legate al radon. Il corpo di tale capitolo è diviso in due paragrafi (e relativi sottoparagrafi) rispettivamente riguardanti le covariate geologiche e di housing (dettagli edilizi). Essendo il radon una variabile ambientale, molte delle covariate possibilmente legate ad esso sono categoriche, poiché frutto di opinione o valutazione di esperti. Di conseguenza il loro studio è basato principalmente su boxplot e test di correlazione statistica, usualmente non parametrici. Abstract La parte III della tesi è la parte di cui all'inizio del sommario, contenente gli studi e i modelli statistici principali usati per raffinare le analisi sviluppate nella parte precedente. Abstract Il settimo capitolo è un minuzioso studio geostatistico fatto sul database RPA2006. Il capitolo otto esamina invece gli studi di correlazione effettuati sul database RPA2014, dedicato alla verifica del se e come il radon varia all'interno di un edificio tra differenti piani e stanze. Abstract Le appendici non sono originali e comprendono: 1) la collezione degli strumenti statistici usati in questo elaborato, con le loro definizioni matematiche (ove possibile); 2) un'introduzione alla teoria geostatistica, nella quale è possibile trovare, almeno, tutti i chiarimenti necessari alla comprensione, almeno generale, dell'analisi fatta.XXVII Ciclo198

A GIS-based modelling approach to identify natural drivers of coral reef abundance in the Northern Myeik Archipelago, Myanmar

To predict the coral abundance of the Northern of Myeik, I compared various progressions of model techniques, including stepwise regression (using OLS), GWR, and Random forest analysis methods, to investigate relationships between coral abundance survey data and environmental variables such as depth, slope, aspect, rugosity, chlorophyll, sea surface temperature, and turbidity. Depth and SST have the most significant effect on predicted coral species abundance. Increased reef abundance was associated with a reduction in sea surface temperature stability and shallower optimum depths. Even then, GWR outperformed the other studied approaches in places with a substantial degree of input-output disagreement. The GWR model production was used to produce a final predicted coral abundance modelling map. The accuracy of the GWR model was determined by using Random forest predict modelling to map and comparing the higher R2 and predicted and observation graphs to the slope and interest value of each model. This sampling tool for a reef prediction model can be used in preference of potential species abundance modelling (e.g., seagrass, mangrove) in future Myanmar coastal management projects, resulting in more accurate predictions and more educated species management decisions. It can assist the Department of Fisheries in making fisheries management decisions and help to keep fish stocks stable in the long run by fostering a greater understanding of key environmental variables