Prostate cancer and industrial pollution Risk around putative focus in a multi-source scenario

Risk of prostate cancer in the proximity of industrial installations: A multicase-control study in Spain (MCC-Spain)

BACKGROUND

Prostate cancer (PC) is the second most frequent tumor in men worldwide; however, its etiology remains largely unknown, with the exception of age and family history. The wide variability in incidence/mortality across countries suggests a certain role for environmental exposures that has not yet been clarified.

OBJECTIVE

To evaluate the association between risk of PC (by clinical profile) and residential proximity to pollutant industrial installations (by industrial groups, groups of carcinogens, and specific pollutants released), within the context of a Spanish population-based multicase-control study of incident cancer (MCC-Spain).

METHODS

This study included 1186 controls and 234 PC cases, frequency matched by age and province of residence. Distances from participants' residences to the 58 industries located in the study area were calculated and categorized into "near" (considering different limits between ≤1 km and ≤ 3 km) or "far" (>3 km). Odds ratios (ORs) and 95 % confidence intervals (95%CIs) were estimated using mixed and multinomial logistic regression models, adjusted for potential confounders and matching variables.

RESULTS

No excess risk was detected near the overall industries, with ORs ranging from 0.66 (≤2 km) to 1.11 (≤1 km). However, positive associations (OR; 95%CI) were found, by industrial group, near (≤3 km) industries of ceramic (2.54; 1.28-5.07), food/beverage (2.18; 1.32-3.62), and disposal/recycling of animal waste (2.67; 1.12-6.37); and, by specific pollutant, near plants releasing fluorine (4.65; 1.45-14.91 at ≤1.5 km) and chlorine (5.21; 1.56-17.35 at ≤1 km). In contrast, inverse associations were detected near industries releasing ammonia, methane, dioxins+furans, polycyclic aromatic hydrocarbons, trichloroethylene, and vanadium to air.

CONCLUSIONS

The results suggest no association between risk of PC and proximity to the overall industrial installations. However, some both positive and inverse associations were detected near certain industrial groups and industries emitting specific pollutants.

Low level exposure to BDE-47 facilitates the development of prostate cancer through TOP2A/LDHA/lactylation positive feedback circuit

2,2',4,4'-tetra brominated diphenyl ether (BDE-47) is one of the most widely distributed congeners of polybrominated diphenyl ethers. While the relationships between BDE-47 exposure and other hormone-dependent cancers (such as breast cancer) are well established, no previous study has examined whether BDE-47 exposure is related to the development of prostate cancer (PCa). Through bulk and single-cell RNA sequencing (scRNA-seq) analyses, as well as in vitro and in vivo experiments, this study aims to investigate the effect of BDE-47 exposure on PCa progression. Herein, we found that low dose BDE-47 promoted the growth of PCa cells (PC3 and LNCaP) in a dose-dependent manner in vitro and in vivo. Based on Comparative Toxicogenomics Database (CTD) and The Cancer Genome Atlas (TCGA), we obtained 34 BDE-47-related and PCa-related genes through screening and overlapping. These genes were significantly enriched in fatty acid metabolism-related gene ontology (GO) terms, which were also enriched for genes targeting BDE-47 obtained from the UniProt. Through scRNA-seq data, certain cell type-specific expression was observed for CYP2E1, PIK3R1, FGF2, and TOP2A in PCa tissues from men. Molecular docking simulation showed that BDE-47 was tightly bound to the protein residues of AOX1, PIK3R1, FGF2, CAV2, CYP2E1 and TOP2A. Further screening in terms of patient overall survival, receiver operating characteristics curve (ROC) curve and Gleason score grading system narrowed the candidate genes down to TOP2A. Mechanistically, the growth-promoting effect of BDE-47 on PCa cells could be reversed by TOP2A inhibitor. RNA-seq followed by experimental verification demonstrated that TOP2A promoted PCa progression through upregulating LDHA and glycolysis. Furthermore, lactate upregulated TOP2A transcription through lactylation of H3K18la in PCa cells, which could be rescued by LDHA knockdown. Taken together, low dose BDE-47 triggered PCa progression through TOP2A/LDHA/lactylation positive feedback circuit, thus revealing epigenetic shifting and metabolic reprogramming underpinning BDE-47-induced carcinogenesis of the prostate.

Mammographic density in the environs of multiple industrial sources

BACKGROUND

Mammographic density (MD), defined as the percentage of dense fibroglandular tissue in the breast, is a modifiable marker of the risk of developing breast cancer. Our objective was to evaluate the effect of residential proximity to an increasing number of industrial sources in MD.

METHODS

A cross-sectional study was conducted on 1225 premenopausal women participating in the DDM-Madrid study. We calculated distances between women's houses and industries. The association between MD and proximity to an increasing number of industrial facilities and industrial clusters was explored using multiple linear regression models.

RESULTS

We found a positive linear trend between MD and proximity to an increasing number of industrial sources for all industries, at distances of 1.5 km (p-trend = 0.055) and 2 km (p-trend = 0.083). Moreover, 62 specific industrial clusters were analyzed, highlighting the significant associations found between MD and proximity to the following 6 industrial clusters: cluster 10 and women living at ≤1.5 km (β = 10.78, 95 % confidence interval (95%CI) = 1.59; 19.97) and at ≤2 km (β = 7.96, 95%CI = 0.21; 15.70); cluster 18 and women residing at ≤3 km (β = 8.48, 95%CI = 0.01; 16.96); cluster 19 and women living at ≤3 km (β = 15.72, 95%CI = 1.96; 29.49); cluster 20 and women living at ≤3 km (β = 16.95, 95%CI = 2.90; 31.00); cluster 48 and women residing at ≤3 km (β = 15.86, 95%CI = 3.95; 27.77); and cluster 52 and women living at ≤2.5 km (β = 11.09, 95%CI = 0.12; 22.05). These clusters include the following industrial activities: surface treatment of metals/plastic, surface treatment using organic solvents, production/processing of metals, recycling of animal waste, hazardous waste, urban waste-water treatment plants, inorganic chemical industry, cement and lime, galvanization, and food/beverage sector.

CONCLUSIONS

Our results suggest that women living in the proximity to an increasing number of industrial sources and those near certain types of industrial clusters have higher MD.

Analysis of the distribution characteristics of prostate cancer and its environmental factors in China

The high incidence and mortality and the increasing trend of prostate cancer has been one of the public health issues in many countries and regions. Meanwhile, the spatio-temporal heterogeneity of prostate cancer implies that lifestyle and ecological changes may be associated with prostate cancer, however, sufficient evidence is still lacking. This paper tried to reveal the spatial and temporal distribution characteristics of prostate cancer in China and explore the potential associations with related socioeconomic and natural condition factors. Data on prostate cancer incidence and mortality in 182 counties (districts) in mainland China from 2014-2016 were collected, and the distribution characteristics of prostate cancer were analyzed using spatiotemporal scan statistic. Spatial regression models and geodetector method were used to analyze the potential associations between meteorological conditions, socioeconomic development, and prostate cancer incidence and mortality. SaTScan, GeoDa, and GeoDetector were used for the above statistical analyses. The high-risk clusters for prostate cancer incidence and mortality were located in southeastern China, and the low-risk clusters were located in north-central China. Spatial regression models showed that the number of industrial enterprises/km² (incidence: β = 0.322, P < 0.001; mortality: β = 0.179, P < 0.001), GDP (incidence:β = 0.553, P < 0.001; mortality: β = 0.324, P < 0.001), number of beds in medical and health institutions/1000 persons (incidence: β = 0.111, P = 0.005; mortality: β = 0.068, P = 0.021), and urbanization rate (incidence: β = 0.156, P < 0.001; mortality: β = 0.100, P < 0.001) were positively associated with the incidence and mortality of prostate cancer. The urbanization rate (incidence: q = 0.185, P < 0.001; mortality: q = 0.182, P < 0.001) has the greatest explanatory power, and the interaction of all factors was bivariate enhanced or nonlinearly enhanced. The distribution of prostate cancer in China has obvious spatial heterogeneity. The incidence and mortality rate of prostate cancer are on the rise, and special plans should be formulated in each region according to local conditions.

Validity of Geolocation and Distance to Exposure Sources from Geographical Information Systems for Environmental Monitoring of Toxic Metal Exposures Based on Correlation with Biological Samples: a Systematic Review

PURPOSE OF REVIEW

In epidemiologic studies, biomarkers are the best possible choice to assess individual exposure to toxic metals since they integrate all exposure sources. However, measuring biomarkers is not always feasible, given potential budgetary and time constraints or limited availability of samples. Alternatively, approximations to individual metal exposure obtained from geographic information systems (GIS) have become popular to evaluate diverse metal-related health outcomes. Our objective was to conduct a systematic review of epidemiological studies that evaluated the validity of GIS-based geolocation and distance to pollutant sources as an approximation of individual metal exposure based on correlation with biological samples.

RECENT FINDINGS

We considered 11 toxic metals: lead (Pb), cadmium (Cd), antimony (Sb), aluminum (Al), arsenic (As), chromium (Cr), nickel (Ni), mercury (Hg), tungsten (W), uranium (U), and vanadium (V). The final review included 12 manuscripts which included seven metals (Pb, Cd, Al, As, Cr, Hg, and Ni). Many studies used geolocation of the individuals to compare exposed (industrial, urban, agricultural, or landfill sources) and unexposed areas and not so many studies used distance to a source. For all metals, except lead, there was more animal than human biosampling to conduct biological validation. We observed a trend towards higher levels of Cd, Cr, Hg, and Pb in biosamples collected closer to exposure sources, supporting that GIS-based proxies for these metals might approximate individual exposure. However, given the low number and heterogeneity of the retrieved studies, the accumulated evidence is, overall, not sufficient. Given the practical benefits and potential of modern GIS technologies, which allow environmental monitoring at a reasonable cost, additional validation studies that include human biosampling are needed to support the use of GIS-based individual exposure measures in epidemiologic studies.

Air pollution and molecular changes in age-related diseases

Assessment of the impact that air contaminants have on health is difficult as this is a complex mixture of substances that varies depending on the time and place. There are many studies on the association between air pollution and increased morbidity and mortality. Before the effect of polluted air is manifested at the level of the organs, an impact can be observed at the molecular level. These include some new biomarkers, like a shortening of the mean telomere length in DNA, dysregulation of gene expression caused by microRNA levels or a variation in the copy number of mitochondrial DNA. These changes may predispose individuals to premature development of age-related diseases and consequently to shortening of life. The common attribute, shared by changes at the molecular level and the development of diseases, is the presence of oxidative stress.

LncRNA OIP5-AS1 inhibits ferroptosis in prostate cancer with long-term cadmium exposure through miR-128-3p/SLC7A11 signaling

Previous studies suggest that cadmium (Cd) is one of the causative factors of prostate cancer (PCa), but the effect of chronic Cd exposure on PCa progression remains unclear. Besides, whether long noncoding RNAs (lncRNAs) are involved in the regulation of prolonged exposure to Cd in PCa needs to be elucidated. In the present study, we found that the serum concentration of Cd in PCa patients was positively correlated with the Gleason score and tumor-node-metastasis (TNM) classification. To simulate chronic Cd exposure in PCa, we subjected PC3 and DU145 cells to long-term, low-dose Cd exposure and further examined tumor behavior. Functional studies identified that chronic Cd exposure promoted cell growth and ferroptosis resistance in vitro and in vivo. Furthermore, we found that lncRNA OIP5-AS1 expression was greatly elevated in PC3 and DU145 cells upon chronic Cd exposure. Dysregulation of OIP5-AS1 expression mediated cell growth and Cd-induced ferroptosis. Mechanistically, we demonstrated that OIP5-AS1 served as an endogenous sponge of miR-128-3p to regulate the expression of SLC7A11, a surrogate marker of ferroptosis. Moreover, miR-128-3p decreased cell viability by enhancing ferroptosis. Taken together, our data indicate that lncRNA OIP5-AS1 promotes PCa progression and ferroptosis resistance through miR-128-3p/SLC7A11 signaling.

An integrated assessment methodology for management of potentially contaminated sites based on public data

Ranking assessment of potentially contaminated sites (PCS) provides a great quantity of information (namely the risk screening list) that is usually examined by environmental managers, and therefore reduces the cost of risk management in terms of site investigation. Here we propose an integrated assessment methodology to establish a risk screening list of PCS in China using the Choquet integral correlation coefficient (ICC), which takes the uncertainty and interaction of PCS attributes into explicit account. The proposed method globally considers the importance and ordered positions of PCS attributes while reflecting their overall ranking. The model evaluation and actual validation results demonstrate the success in PCS ranking by the proposed method, which is superior to other methods such as the intuitionistic fuzzy multiple attribute decision-making, the technique for order preference by similarity to an ideal solution, and the weighted average. The resulting spatial distribution of Choquet ICC indicates that high-attention PCS in China are mainly located in Guangdong, Jiangsu, Zhejiang, and Shandong Provinces. This study is the first attempt to conduct a ranking assessment of PCS across China. The proposed assessment method based on Choquet ICC offers a step towards establishing a risk screening list of PCS globally.

Health risks for the population living near petrochemical industrial complexes. 1. Cancer risks: A review of the scientific literature

Petrochemical complexes and oil refineries are well known sources of a wide range of environmental pollutants. Consequently, the potential harmful health effects of living near these facilities is a topic of concern among the population living in the neighborhood. Anyhow, the number of studies carried out on this issue is rather limited and, in some cases, results are even slightly contradictory. The present Review was aimed at assessing whether living in the vicinity of petrochemical industries and oil refineries is associated with a higher incidence of cancer and cancer mortality. In this sense, up to 23 investigations were found in PubMed and Scopus databases. According to the type of cancer, leukemia and other hematological malignancies were reported as the main types of cancer for populations living in the neighborhood of petrochemical industries. This was concluded based on studies performed in Taiwan, Spain, United Kingdom, Italy and Nigeria. In contrast, no association was found in 4 different investigations conducted in Sweden, Finland and USA with the same purpose. Other scientific studies reported a high incidence of lung and bladder cancer in Taiwan, Italy and USA, as well as an excess mortality of bone, brain, liver, pleural, larynx and pancreas cancers in individuals living near petrochemical complexes from Taiwan, Spain, Italy, United Kingdom and USA. Thus, human exposure to certain carcinogenic pollutants emitted from petrochemical industries might increase the incidence of some cancers and cancer mortality. Anyway, since the limited number of investigations conducted until now, further studies are required in order to corroborate -in a more generalized way-this conclusion.

Cancer Incidence Trends in the Oil Shale Industrial Region in Estonia

Large oil shale resources are found in Eastern Estonia, where the mineral resource is mined, excavated, and used for electricity generation and shale oil extraction. During industrial activities in the last 100 years, pollutants have been emitted in large amounts, some of which are toxic and carcinogenic. The current study aims to analyse time trends in cancer incidence in the oil shale industry-affected areas and compare them with overall cancer incidence rates and trends in Estonia. We analysed Estonian Cancer Registry data on selected cancer sites that have been previously indicated to have relationships with industrial activities like oil shale extraction. We included lung cancer, kidney cancer, urinary bladder cancer, leukaemia, breast cancer, and non-Hodgkin's lymphoma. A statistically significantly higher lung cancer age-standardized incidence rate (ASIR) was found during the study period (1992-2015) only in males in the oil shale areas as compared to males in Estonia overall: 133.6 and 95.5 per 100,000, respectively. However, there appeared to be a statistically significant (p < 0.05) decrease in the lung cancer ASIR in males in the oil shale areas (overall decrease 28.9%), whereas at the same time, there was a significant increase (p < 0.05) in non-oil shale areas (13.3%) and in Estonia overall (1.5%). Other cancer sites did not show higher ASIRs in the oil shale industrial areas compared to other areas in Estonia. Possible explanations could be improved environmental quality, socio-economic factors, and other morbidities.

Cancer Mortality and Deprivation in the Proximity of Polluting Industrial Facilities in an Industrial Region of Spain

Residential proximity to industrial facilities that release pollutants is a source of exposure to a high number of toxics, many of them known or suspected carcinogens. The objective of the study was to analyze the association between lung, larynx, bladder, and kidney cancer mortality and deprivation in areas proximate to polluting industrial facilities in Cadiz, a highly industrialized province in Spain. An ecological study at census tract level was carried out to estimate the mortality rates associated with deprivation and proximity to polluting industrial facilities (1–5 km) using the Besag–York–Mollié model. The results show a negative social gradient for lung and larynx cancers in males and greater risk of lung cancer was observed in the least deprived areas in females. These associations were found regardless the distance to industrial facilities. Increasing excess risk (relative risk; 95% credibility interval) of lung cancer for males (1.09; 1.02–1.16 at 5 km vs 1.24; 1.08–1.41 at 1 km) and bladder cancer for males (1.11; 1.01–1.22 at 5 km vs 1.32; 1.08–1.60 at 1 km) and females (1.32; 1.04–1.69 at 4 km vs 1.91; 1.28–2.86 at 1 km) was found as proximity to polluting industrial facilities increased. For kidney cancer, high risks were observed near such facilities for both sexes. Knowing the possible influence of industrial pollution and social inequalities over cancer risk allows the definition of policies aimed at reducing the risk.

Estimating the occurrence of traffic accidents near school locations: A case study from Valencia (Spain) including several approaches

Traffic safety around school locations is a topic of particular interest given the large number of vulnerable users, such as pedestrians or cyclists, that commute to them at certain times of the day. A dataset of traffic accidents recorded in Valencia (Spain) during 2014 and 2015 is analyzed in order to estimate the effects that school locations produce on traffic risk within their surroundings. The four typologies of school in this city according to the academic levels they offer (All-level, Preschool, Primary, Secondary) are distinguished and taken into consideration for the analysis. Two time windows comprising the starting time in the morning and the evening time once day school has ended are analyzed independently. Several statistical methods are used, including observed vs expected ratios, macroscopic conditional autoregressive modelling, logistic regression in the context of a case-control study design and risk modelling in relation to several school locations. The distances to each type of school and a set of environmental, traffic-related, demographic and socioeconomic covariates are employed for the analysis. The macroscopic modelling of accident counts and the modelling of risk as a function of the distance to each type of school serves to confirm that proximity to a school has an effect on the incidence of traffic accidents in particular time windows. Specifically, school types coexisting in Valencia show differential behaviour in this regard. In addition, several covariates have displayed a positive (bus stop density, complex intersections, main road length) and negative (land use entropy) association with accident counts in the time windows investigated. Finally, the definition of a case-control study design enabled us to observe some differences undetected by the macroscopic approaches that would require further research.

Different spatial pattern of municipal prostate cancer mortality in younger men in Spain

Background

Prostate cancer (PC) primarily affects elderly men. However, the specific features of cases diagnosed at younger ages (<65 years) suggest that they may represent a different clinical subtype. Our aim was to assess this suggestion by contrasting the geographical PC mortality and hospital admissions patterns in Spain for all ages to those in younger men.

Methods

The Spanish National Institute of Statistics supplied data on PC mortality, hospital admission, and population data. We estimated the expected town-specific number of deaths and calculated the standardized mortality ratios. Spatial autoregressive models of Besag-York-Mollié provided smoother municipal estimators of PC mortality risk (all ages; <65 years). We computed the provincial age-standardized rate ratios of PC hospital admissions (all men; <60 years) using Spanish rates as the reference.

Results

A total of 29,566 PC deaths (6% among those <65 years) were registered between 2010–2014, with three high-mortality risk zones: Northwest Spain; Southwest Andalusia & Granada; and a broad band extending from the Pyrenees Mountains to the north of Valencia. In younger men, the spatial patterns shared the high risk of mortality in the Northwest but not the central band. The PC hospital discharge rates confirmed a North-South gradient but also low mortality/high admission rates in Madrid and Barcelona and the opposite in Southwest Andalusia.

Conclusion

The consistent high PC mortality/morbidity risk in the Northwest of Spain indicates an area with a real excess of risk. The different spatial pattern in younger men suggests that some factors associated with geographical risk might have differential effects by age. Finally, the regional divergences in mortality and morbidity hint at clinical variability as a source of inequity within Spain.

Non-linear spatial modeling of rat sightings in relation to urban multi-source foci

The brown rat has been living with humans in a wide variety of environmental contexts; it adversely affects public health by transmission of pathogens that can cause human diseases and allergies. Understanding behavioral aspects and environmental factors of pest species can contribute to their effective management and control. This aim of this study was to investigate the spatial distribution of rats in Latina district of Madrid (Spain), and its relationship with several potential multi-source foci. A focus is any particular social and environmental urban scenario that favors the clustering and proliferation of rats. We have developed a statistical framework to provide valid information on the spatial distribution and behavior of the rats around identified potential foci that favor the concentration of rats in urban environments. We extended the standard Poisson regression model by the inclusion of a multiplicative non-linear function of the distance, an unstructured random effect, and a spatial random effect to account for the spatial structure of socio-demographic and environmental covariates were also considered in the model to control for potential confusion. We found evidence of an association between the spatial distribution of rats aggregated by census tracts and distance to foci, and this association was controlled by the covariates considered in this study.

Particulate Matter (Fine Particle) and Urologic Diseases

Particulate matter (PM) has been found to damage vital body organs, including the lungs and heart, through vascular damage and oxidative stress. Recently, renal function and chronic urologic diseases have also been found to be related to PM. To investigate this, we reviewed the characteristics of PM related to renal toxicity, including recent studies on the associations of urologic diseases with PM. PM can include constituents that cause renal toxicity, such as lead, cadmium, arsenic, and crystalline silica, which result in renal tubular or interstitial damage. Since 2008, 7 studies have evaluated the renal effects of PM. Two prospective cohort studies and a quantitative study of consecutive patients showed that PM may be related to decreased renal function, as shown by the estimated glomerular filtration rate of diseased or aged participants. Two cross-sectional studies found an association between PM and chronic kidney disease. One of those studies identified the specific renal diseases of immunoglobulin A nephropathy and membranous nephropathy. Two studies that analyzed renal cancer and PM showed no evidence that renal cancer is related to PM. Nine studies were evaluated regarding the relationship of bladder and prostate cancer with PM. The evidence for an association of PM with bladder and prostate cancer is still inconclusive. Although some recently published studies have shown a significant relationship, the causal relationship is not clear. Further well-designed studies on specific renal diseases are required.

Childhood cancer in small geographical areas and proximity to air-polluting industries

AIM

Pediatric cancer has been associated with exposure to certain environmental carcinogens. The purpose of this work is to analyse the relationship between environmental pollution and pediatric cancer risk.

METHOD

We analysed all incidences of pediatric cancer (<15) diagnosed in a Spanish region during the period 1998-2015. The place of residence of each patient and the exact geographical coordinates of main industrial facilities was codified in order to analyse the spatial distribution of cases of cancer in relation to industrial areas. Focal tests and focused Scan methodology were used for the identification of high-incidence-rate spatial clusters around the main industrial pollution foci.

RESULTS

The crude rate for the period was 148.0 cases per 1,000,0000 children. The incidence of pediatric cancer increased significantly along the period of study. With respect to spatial distribution, results showed significant high incidence around some industrial pollution foci group and the Scan methodology identify spatial clustering. We observe a global major incidence of non Hodgkin lymphomas (NHL) considering all foci, and high incidence of Sympathetic Nervous System Tumour (SNST) around Energy and Electric and organic and inorganic chemical industries foci group. In the analysis foci to foci, the focused Scan test identifies several significant spatial clusters. Particularly, three significant clusters were identified: the first of SNST was around energy-generating chemical industries (2 cases versus the expected 0.26), another of NHL was around residue-valorisation plants (5 cases versus the expected 0.91) and finally one cluster of Hodgkin lymphoma around building materials (3 cases versus the expected 2.2) CONCLUSION: Results suggest a possible association between proximity to certain industries and pediatric cancer risk. More evidences are necessary before establishing the relationship between industrial pollution and pediatric cancer incidence.

Residential greenness and risk of prostate cancer: A case-control study in Montreal, Canada

BACKGROUND

Recent studies suggest that exposure to greenness favors several health outcomes. We assessed whether living in the proximity of greener areas was related to prostate cancer incidence in a population-based case-control study in Montreal, Canada.

MATERIALS AND METHODS

Interviews eliciting lifetime addresses were conducted with 1933 prostate cancer cases diagnosed in 2005-2009 and 1994 population controls. Odds ratios (OR) and 95% confidence intervals (CI) estimated the association between residential greenness, both at recruitment (2005-2009) and about ten years prior (1996), defined by the normalized difference vegetation index (NDVI) around the home, and prostate cancer risk. Three models were developed adjusting for age, individual characteristics, and individual and ecological characteristics, estimating relative risk in relation to an interquartile range (IQR) increase of the NDVI.

RESULTS

We observed inverse associations between greenness measured within home buffers of 150m, 300m, 500m and 1000m, at both time points, and risk of prostate cancer, independently of individual and ecological characteristics. For instance, using a buffer of 300m, the OR for an IQR increase of 0.11 in NDVI at the time of recruitment was 0.82 (95%CI 0.74-0.92). The corresponding OR for an IQR increase of 0.15 in NDVI in 1996 was 0.86 (95%CI 0.74-1.00). There were little differences in risks according to buffer size, the time point of exposure, when considering prostate cancer aggressiveness, or when restricting controls to men recently screened for prostate cancer to reduce the likelihood of undiagnosed cancer among them.

CONCLUSION

Men living in greener areas, either recently or about a decade earlier, had lower risks of prostate cancer, independently of socio-demographic and lifestyle factors. These observations are novel and require confirmation.

Residential radon and COPD. An ecological study in Galicia, Spain

PURPOSE

Radon is a human lung carcinogen but it might be linked with other respiratory diseases. We aimed to assess the relationship between residential radon exposure and COPD (chronic obstructive pulmonary disease) prevalence and hospital admissions at a municipal level.

MATERIALS AND METHODS

We designed an ecological study where we included those municipalities with at least three radon measurements. Using mixed Poisson regression models, we calculated the relative risk (RR) for COPD for each 100 Bq/m³ of increase in radon concentration and also the relative risk for COPD using a cut-off point of 50 Bq/m³. We did not have individual data on cigarette smoking and therefore we used a proxy (bladder cancer standardized mortality rate) that has proved to account for tobacco consumption. We performed separate analyses for sex and also sensitivity analysis considering age and rurality.

RESULTS

A total of 3040 radon measurements and 49,393 COPD cases were included. The relative risk for COPD prevalence was 0.95 (95% CI: 0.92-0.97) while for hospital admissions the RR was 1.04 (95% CI: 1.00-1.10) for each 100 Bq/m³. Relative risks were higher for women compared to men. Using a categorical analysis with a cut-off point of 50 Bq/m³, the RR for COPD prevalence was 1.06 (95% CI: 1.02-1.10) and for hospital admissions it was 1.08 (95% CI: 1.00-1.17) for women living in municipalities with more than 50 Bq/m³. All risks were also higher for women. No relevant differences were observed for age, rurality or other categories for radon exposure.

CONCLUSION

While the influence of radon on COPD prevalence is unclear depending on the approach used, it seems that residential radon might increase the risk of hospital admissions in COPD patients. Women have a higher risk than men in all situations. Since this is an ecological study, results should be interpreted cautiously.

Association between air pollution and benign prostatic hyperplasia: An ecological study

Benign prostate hyperplasia (BPH) is a prevalent medical condition; however, little is known about the effect of environmental factors. Therefore, we conducted surveys to examine the association between air pollution and the risk of BPH in South Korea between May 2010 and April 2013, yielding data for 1,734 men. Air pollution information was obtained from the National Air Pollutants Emission 2010 report. Logistic regression analyses were conducted after adjusting for potential confounders. The International Prostate Symptom Score significantly increased with increasing per capita air pollutant emissions. The risk of BPH increased as the overall concentration of air pollutants increased (odds ratio [OR], 2.23; 95% confidence interval [CI], 1.55-3.21). In particular, nitrogen oxides (OR, 1.73; 95% CI, 1.25-2.39) and sulfur oxides (OR, 2.02; 95% CI, 1.42-2.88) showed a dose-dependent association. Our findings support a positive association between the risk of BPH and air pollution.

Impact of large industrial emission sources on mortality and morbidity in Chile: A small-areas study

Chile suffers significant pollution from large industrial emitters associated with the mining, metal processing, paper production, and energy industries. The aim of this research was to determine whether the presence of large industrial facilities (i.e. coal- and oil-fired power plants, pulp and paper mills, mining facilities, and smelters) affects mortality and morbidity rates in Chile. For this, we conducted an ecological study that used Chilean communes as small-area observation units to assess mortality and morbidity. Public databases provided information on large pollution sources relevant to Chile. The large sources studied were oil- and coal-fired power plants, copper smelters, pulp and paper mills, and large mining facilities. Large sources were filtered by first year of production, type of process, and size. Mortality and morbidity data were acquired from public national databases, with morbidity being estimated from hospitalization records. Cause-specific rates were calculated for the main outcomes: cardiovascular, respiratory, cancer; and other more specific health outcomes. The impact of the large pollution sources was estimated using Bayesian models that included spatial correlation, overdispersion, and other covariates. Large and significant increases in health risks (around 20%-100%) were found for communes with power plants and smelters for total, cardiovascular, respiratory, all-cancer, and lung cancer mortality. Higher hospitalization rates for cardiovascular disease, respiratory disease, cancer, and pneumonia (20-100%) were also found for communes with power plants and smelters. The impacts were larger for men than women in terms of both mortality and hospitalizations. The impacts were also larger when the sources were analyzed as continuous (production volume) rather than dichotomous (presence/absence) variables. In conclusion, significantly higher rates of total cardiovascular, respiratory, all-cancer and lung cancer mortality and cardiovascular, respiratory, cancer and pneumonia hospitalizations were observed in communes with power plants and smelters.

Breast and prostate cancer mortality and industrial pollution

We investigated whether there might be an excess of breast and prostate cancer mortality among the population residing near Spanish industries, according to different categories of industrial groups. An ecologic study was designed to examine breast and prostate cancer mortality at a municipal level (period 1997-2006). Population exposure to pollution was estimated by means of distance from town of residence to industrial facilities. Using Besag-York-Mollié regression models with Integrated Nested Laplace approximations for Bayesian inference, we assessed the relative risk of dying from these tumors in 2-, 3-, 4-, and 5-km zones around installations, and analyzed the effect of category of industrial group. For all sectors combined, no excess risk was detected. However, excess risk of breast cancer mortality (relative risk, 95% credible interval) was detected near mines (1.10, 1.00-1.21 at 4 km), ceramic industries (1.05, 1.00-1.09 at 5 km), and ship building (1.12, 1.00-1.26 at 5 km), and excess risk of prostate cancer was detected near aquaculture for all distances analyzed (from 2.42, 1.53-3.63 at 2 km to 1.63, 1.07-2.36 at 5 km). Our findings do not support that residing in the vicinity of pollutant industries as a whole (all industrial sectors combined) is a risk factor for breast and prostate cancer mortality. However, isolated statistical associations found in our study with respect to specific industrial groups warrant further investigation.

Causal versus spurious spatial exposure-response associations in health risk analysis

Many recent health risk assessments have noted that adverse health outcomes are significantly statistically associated with proximity to suspected sources of health hazard, such as manufacturing plants or point sources of air pollution. Using geographic proximity to sources as surrogates for exposure to (possibly unknown) releases, spatial ecological studies have identified potential adverse health effects based on significant regression coefficients between risk rates and distances from sources in multivariate statistical risk models. Although this procedure has been fruitful in identifying exposure-response associations, it is not always clear whether the resulting regression coefficients have valid causal interpretations. Spurious spatial regression and other threats to valid causal inference may undermine practical efforts to causally link health effects to geographic sources, even when there are clear statistical associations between them. This paper demonstrates the methodological problems by examining statistical associations and regression coefficients between spatially distributed exposure and response variables in a realistic data set for California. We find that distance from "nonsense" sources (such as arbitrary points or lines) are highly statistically significant predictors of cause-specific risks, such as traffic fatalities and incidence of Kaposi's sarcoma. However, the signs of such associations typically depend on the distance scale chosen. This is consistent with theoretical analyses showing that random spatial trends (which tend to fluctuate in sign), rather than true causal relations, can create statistically significant regression coefficients: spatial location itself becomes a confounder for spatially distributed exposure and response variables. Hence, extreme caution and careful application of spatial statistical methods are warranted before interpreting proximity-based exposure-response relations as evidence of a possible or probable causal relation.

Proximity to mining industry and cancer mortality

Mining installations are releasing toxic substances into the environment which could pose a health problem to populations in their vicinity. We sought to investigate whether there might be excess cancer-related mortality in populations residing in towns lying in the vicinity of Spanish mining industries governed by the Integrated Pollution Prevention and Control Directive, and the European Pollutant Release and Transfer Register Regulation, according to the type of extraction method used. An ecologic study was designed to examine municipal mortality due to 32 types of cancer, across the period 1997 through 2006. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Poisson regression models, using the Bayesian conditional autoregressive model proposed by Besag, York and Molliè and Integrated Nested Laplace Approximations for Bayesian inference, were used: to analyze risk of dying from cancer in a 5-kilometer zone around mining installations; effect of type of industrial activity; and to conduct individual analyses within a 50-kilometer radius of each installation. Excess mortality (relative risk, 95% credible interval) of colorectal cancer (1.097, 1.041-1.157), lung cancer (1.066, 1.009-1.126) specifically related with proximity to opencast coal mining, bladder cancer (1.106, 1.016-1.203) and leukemia (1.093, 1.003-1.191) related with other opencast mining installations, was detected among the overall population in the vicinity of mining installations. Other tumors also associated in the stratified analysis by type of mine, were: thyroid, gallbladder and liver cancers (underground coal installations); brain cancer (opencast coal mining); stomach cancer (coal and other opencast mining installations); and myeloma (underground mining installations). The results suggested an association between risk of dying due to digestive, respiratory, hematologic and thyroid cancers and proximity to Spanish mining industries. These associations were dependent on the type of mine.

Risk of cancer mortality in spanish towns lying in the vicinity of pollutant industries

Spatial aggregation of different industrial facilities leads to simultaneous release of pollutant emissions. Our objective is to study cancer mortality risk associated with residence in the vicinity of pollutant factories. We used data on industries for year 2007 (3458 facilities). For the 8,098 Spanish towns, we defined a factor with 4 levels based on the number of factories in a radius of 2.5 km from the centroid of each town (industrial factor). We also used data of land cover use to approximate the percentage of municipal land used for industrial activities in each Spanish town (land-used variable). For both variables we fitted Poisson models with random terms to account for spatial variation. We estimated risk trends related with increasing number of factories or percentage of land used for industrial activities. We studied 33 cancer causes. For the industrial factor, 11 causes showed trend associated with increasing factor level. For the land use variable, 8 causes showed statistically significant risks. Almost all tumours related to the digestive system and the respiratory system showed increased risks. Thus mortality by these tumours could be associated to residence in towns nearby industrial areas with positive trend linked to increasing levels of industrial activity.

Proximity to wood industries and respiratory symptoms in children: a sensitivity analysis

Increased prevalence of respiratory and irritation symptoms was found in children who live near a large wood industrial park. Proximity to the wood industries was used as indicator of exposure. This study describes a sensitivity analysis for the results of the survey. All the children (3-14 years) living in the area were surveyed through a parental questionnaire (n=3854) and their addresses were geocoded. The distances from each child's home and school to the closest industry were combined, weighted and used as an indicator of exposure. A sensitivity analysis was performed to check 1) the robustness of the results to the choice of weights used for defining the exposure indicator, 2) the effect of outliers on risk estimates and 3) the sensitivity on the functional form used for modeling the dose-response function. The choice of the weights did not influence the association between proximity to the industries and respiratory symptoms. Excluding the subjects who lived far away from the industries showed that in a radius of 5km from the industries the study did not had enough power to estimate a gradient in the dose-response function. Besides, results were sensitive to the choice of the functional form used for modeling the minimum distance. The sensitivity analyses confirmed the overall increasing trend of respiratory symptoms with proximity to the industries and pointed out that all the assumptions made for defining a proxy of exposure need to be carefully checked.