Environmental exposure to emissions from petrochemical sites and lung cancer: the lower Mississippi interagency cancer study

Geographic Patterns in U.S. Lung Cancer Mortality and Cigarette Smoking

BACKGROUND

Despite the success of smoking cessation campaigns, lung cancer remains the leading cause of cancer death in the U.S. Variations in smoking behavior and lung cancer mortality are evident by sex and region.

METHODS

Applying geospatial methods to lung cancer mortality data from the National Vital Statistics System and county-level estimates of smoking prevalences from the NCI's Small Area Estimates of Cancer-Related Measures, we evaluated patterns in lung cancer mortality rates (2005-2018) in relation to patterns in ever cigarette smoking prevalences (1997-2003).

RESULTS

Overall, ever smoking spatial patterns were generally associated with lung cancer mortality rates, which were elevated in the Appalachian region and lower in the West for both sexes. However, we also observed geographic variation in mortality rates that is not explained by smoking. Using Lee's L statistic for assessing bivariate spatial association, we identified counties where the ever smoking prevalence was low and lung cancer rates were high. We observed a significant cluster of counties (n = 25; P values ranging from 0.001 to 0.04) with low ever smoking prevalence and high mortality rates among females around the Mississippi River region south of St. Louis, Missouri and a similar and smaller cluster among males in Western Mississippi (n = 12; P values ranging from 0.002 to 0.03) that has not been previously described.

CONCLUSIONS

Our analyses identified U.S. counties where factors other than smoking may be driving lung cancer mortality.

IMPACT

These novel findings highlight areas where investigation of environmental and other risk factors for lung cancer is needed.

Proximity to Oil Refineries and Risk of Cancer: A Population-Based Analysis

Background

The association between proximity to oil refineries and cancer rate is largely unknown. We sought to compare the rate of cancer (bladder, breast, colon, lung, lymphoma, and prostate) according to proximity to an oil refinery in Texas.

Methods

A total of 6 302 265 persons aged 20 years or older resided within 30 miles of an oil refinery from 2010 to 2014. We used multilevel zero-inflated Poisson regression models to examine the association between proximity to an oil refinery and cancer rate.

Results

We observed that proximity to an oil refinery was associated with a statistically significantly increased risk of incident cancer diagnosis across all cancer types. For example, persons residing within 0-10 (risk ratio [RR] = 1.13, 95% confidence interval [CI] = 1.07 to 1.19) and 11-20 (RR = 1.05, 95% CI = 1.00 to 1.11) miles were statistically significantly more likely to be diagnosed with lymphoma than individuals who lived within 21-30 miles of an oil refinery. We also observed differences in stage of cancer at diagnosis according to proximity to an oil refinery. Moreover, persons residing within 0-10 miles were more likely to be diagnosed with distant metastasis and/or systemic disease than people residing 21-30 miles from an oil refinery. The greatest risk of distant disease was observed in patients diagnosed with bladder cancer living within 0-10 vs 21-30 miles (RR = 1.30, 95% CI = 1.02 to 1.65), respectively.

Conclusions

Proximity to an oil refinery was associated with an increased risk of multiple cancer types. We also observed statistically significantly increased risk of regional and distant/metastatic disease according to proximity to an oil refinery.

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.

Regional inequalities in benzene exposures across the European petrochemical industry: A Bayesian multilevel modelling approach

BACKGROUND

Pollutants released from the petrochemical industry are thought to increase the risk of mortality in fence-line communities, yet the results from previous studies are often inconsistent and lack a global perspective, hampered by the absence of cohesive cross-country research.

OBJECTIVES

To provide the first Pan-European analysis of benzene exposures from the petrochemical industry, connecting polluting practices to pollution episodes and disparities in regional mortality rates, identifying the measures of best environmental practice to mitigate adverse outcomes.

METHODS

The activity, classification and location of onshore petrochemical facilities within EU-28 Member States were extracted from the 'European Pollutant Release and Transfer Register' (E-PRTR), which holds records on 31,753 industrial operations for the reporting period of 2007-15. Parent company records were collected from the Moody's Analytics Amadeus database of 487,338 active companies across Europe. The EUROSTAT census provided records of income, life expectancy, and the underlying demographics used to calculate standardised health outcomes based on 9,936 sub-populations within the NUTS2 regions. The European Environment Agency provided ambient concentrations of benzene from 579 air quality stations. Bayesian multilevel models were constructed to account for variability caused by spatial hierarchical structures, uncertainty in the estimates, and to incorporate both individual and group-level influences.

RESULTS

Higher levels of benzene emissions from petrochemical operations, both overall and in terms of specific pollution events, were associated with increased mortality rates for nearby residential populations, particularly in areas with socioeconomic deprivation. We identify uneven patterns of polluting practices within the industry, and locations that require epidemiological studies.

CONCLUSIONS

While petrochemical facilities in all European Union regions are regulated to be compliant with the annual average benzene limit of 5 μg/m3, uneven exposures still present regional health inequalities. We recommend extending benzene regulations to an hourly or daily limit, alongside the strengthening of regulation for other toxic petrochemical releases.

Risks and burden of lung cancer incidence for residential petrochemical industrial complexes: A meta-analysis and application

BACKGROUND

Lung cancer is one of the most common cancers in the world. Higher incidence of lung cancer may be associated with residential proximity to a petrochemical industrial complex (PIC) due to exposure to various carcinogens, although results from previous epidemiologic studies remain inconclusive. Because disease burden due to residential inequality is a public health and societal concern, this study analyzed published data to estimate lung cancer incidence in association with residential proximity to PICs.

METHODS

We performed a meta-analysis on selected epidemiologic studies that met the following criteria: lung cancer incidence was coded by the International Classification of Diseases; exposure groups were clearly defined as residents living near PICs; and confidence intervals were available or calculable from original articles. We further applied a population attributable factor (PAF) method to estimate disease burden attributable to living near PICs in 22 European Union (EU) countries.

RESULTS

Meta-analysis included six studies with a total of 466,066 residents living near PICs in six countries. Residents living near PICs had a 19% higher risk of lung cancer compared to those who lived farther away (95% CI = 1.06-1.32). By sex, risks were higher and more significant for females (RR = 1.29; 95% CI = 1.09-1.54; P = 0.004) than males (RR = 1.12; 95% CI = 0.95-1.33; P = 0.173). By location, only groups in Europe had a significantly greater risk of lung cancer with exposure to PICs (95% CI = 1.03-1.33; P = 0.019), although groups in other locations showed similar trends. By bona fide observation, observation of residents for at least seven years provided sufficient latency to estimate risk (RR = 1.25; 95% CI = 1.17-1.34; P < 0.001). Regarding burden of lung cancer in 22 EU countries, 494 males and 478 females were attributed to living in the vicinity of a PIC annually.

CONCLUSIONS

Lung cancer incidence is significantly higher in individuals living near PICs. This result provides strong epidemiologic evidence for further policy to regulate potential pollutants near PICs.

HIGHLIGHTS

Higher incident rates of lung cancer for residents living close to petrochemical industry complex.

Residents' Self-Reported Health Effects and Annoyance in Relation to Air Pollution Exposure in an Industrial Area in Eastern-Estonia

Eastern Estonia has large oil shale mines and industrial facilities mainly focused on electricity generation from oil shale and shale oil extraction, which produce high air pollution emissions. The "Study of the health impact of the oil shale sector-SOHOS" was aimed at identifying the impacts on residents' health and annoyance due to the industrial processing. First, a population-wide survey about health effects and annoyance was carried out. Second, the total and oil shale sectors' emitted concentrations of benzene, phenol, and PM2.5 were modelled. Third, the differences between groups were tested and relationships between health effects and environmental pollution studied using multiple regression analysis. Compared to the control groups from non-industrial areas in Tartu or Lääne-Viru, residents of Ida-Viru more frequently (p < 0.05) reported wheezing, chest tightness, shortness of breath, asthma attacks, a long-term cough, hypertension, heart diseases, myocardial infarction, stroke, and diabetes. All health effects except asthma were reported more frequently among non-Estonians. People living in regions with higher levels of PM2.5, had significantly higher odds (p < 0.05) of experiencing chest tightness (OR = 1.13, 95% CI 1.02-1.26), shortness of breath (1.16, 1.03-1.31) or an asthma attack (1.22, 1.04-1.42) during the previous year. People living in regions with higher levels of benzene had higher odds of experiencing myocardial infarction (1.98, 1.11-3.53) and with higher levels of phenol chest tightness (1.44, 1.03-2.00), long-term cough (1.48, 1.06-2.07) and myocardial infarction (2.17, 1.23-3.83). The prevalence of adverse health effects was also higher among those who had been working in the oil shale sector. Next to direct health effects, up to a quarter of the residents of Ida-Viru County were highly annoyed about air pollution. Perceived health risk from air pollution increased the odds of being annoyed. Annoyed people in Ida-Viru had significantly higher odds of experiencing respiratory symptoms during the last 12 months, e.g., wheezing (2.30, 1.31-4.04), chest tightness (2.88, 1.91-4.33 or attack of coughing (1.99, 1.34-2.95).

Lung cancer mortality of residents living near petrochemical industrial complexes: a meta-analysis

BACKGROUND

Lung cancer, as the leading cause of cancer mortality worldwide, has been linked to environmental factors, such as air pollution. Residential exposure to petrochemicals is considered a possible cause of lung cancer for the nearby population, but results are inconsistent across previous studies. Therefore, we performed a meta-analysis to estimate the pooled risk and to identify possible factors leading to the heterogeneity among studies.

METHODS

The standard process of selecting studies followed the Cochrane meta-analysis guideline of identification, screening, eligibility, and inclusion. We assessed the quality of selected studies using the Newcastle-Ottawa scale. Reported point estimates and 95% confidence intervals were extracted or calculated to estimate the pooled risk. Air quality standards were summarized and treated as a surrogate of exposure to air pollution in the studied countries. Funnel plots, Begg's test and Egger's test were conducted to diagnose publication bias. Meta-regressions were performed to identify explanatory variables of heterogeneity across studies.

RESULTS

A total of 2,017,365 people living nearby petrochemical industrial complexes (PICs) from 13 independent studied population were included in the analysis. The pooled risk of lung cancer mortality for residents living nearby PICs was 1.03-fold higher than people living in non-PIC areas (95% CI = 0.98-1.09), with a low heterogeneity among studies (I 2  = 25.3%). Such effect was stronger by a factor of 12.6% for the year of follow-up started 1 year earlier (p-value = 0.034).

CONCLUSIONS

Our meta-analysis gathering current evidence suggests only a slightly higher risk of lung cancer mortality among residents living nearby PICs, albeit such association didn't receive statistically significance. Reasons for higher risks of early residential exposure to PICs might be attributable to the lack of or less stringent air pollution regulations.

Mortality and morbidity in a population exposed to multiple sources of air pollution: A retrospective cohort study using air dispersion models

BACKGROUND AND AIMS

A landfill, an incinerator, and a refinery plant have been operating since the early 1960s in a contaminated site located in the suburb of Rome (Italy). To evaluate their potential health effects, a population-based retrospective cohort study was conducted using dispersion modeling for exposure assessment.

METHODS

A fixed cohort was enrolled in the Rome Longitudinal Study in 2001, mortality and hospitalizations were followed-up until 2010. Exposure assessments to the landfill (H2S), the incinerator (PM10), and the refinery plant (SOX) were performed for each subject using a Lagrangian dispersion model. Individual and small-area variables were available (including exposures levels to NO2 from traffic and diesel trucks). Cox regression analysis was performed (hazard ratios, HRs, 95% CI) using linear terms for the exposures (5th-95th percentiles difference). Single and bi-pollutant models were run.

RESULTS

The cohort included 85,559 individuals. The estimated annual average exposures levels were correlated. H2S from the landfill was associated with cardiovascular hospital admissions in both genders (HR 1.04 95% CI 1.00-1.09 in women); PM10 from the incinerator was associated with pancreatic cancer mortality in both genders (HR 1.40 95% CI 1.03-1.90 in men, HR 1.47 95% CI 1.12-1.93 in women) and with breast morbidity in women (HR 1.13 95% CI 1.00-1.27). SOx from the refinery was associated with laryngeal cancer mortality in women (HR 4.99 95% CI 1.64-15.9) and respiratory hospital admissions (HR 1.13 95% CI 1.01-1.27).

CONCLUSIONS

We found an association of the pollution sources with some cancer forms and cardio-respiratory diseases. Although there was a high correlation between the estimated exposures, an indication of specific effects from the different sources emerged.

A comparison between self-reported and GIS-based proxies of residential exposure to environmental pollution in a case-control study on lung cancer

In epidemiological studies both questionnaire results and GIS modeling have been used to assess exposure to environmental risk factors. Nevertheless, few studies have used both these techniques to evaluate the degree of agreement between different exposure assessment methodologies. As part of a case-control study on lung cancer, we present a comparison between self-reported and GIS-derived proxies of residential exposure to environmental pollution. 649 subjects were asked to fill out a questionnaire and give information about residential history and perceived exposure. Using GIS, for each residence we evaluated land use patterns, proximity to major roads and exposure to industrial pollution. We then compared the GIS exposure-index values among groups created on the basis of questionnaire responses. Our results showed a relatively high agreement between the two methods. Although none of these methods is the "exposure gold standard", understanding similarities, weaknesses and strengths of each method is essential to strengthen epidemiological evidence.

The impact of petrochemical industrialisation on life expectancy and per capita income in Taiwan: an 11-year longitudinal study

BACKGROUND

Petrochemical industries have been identified as important sources of emissions of chemical substances, and adverse health outcomes have been reported for residents who live nearby. The purpose of the current study was to examine the adverse effects of petrochemical industrialization in Taiwan on the life expectancy and personal income of people living in nearby communities.

METHODS

This study compared life expectancies and personal income between one industrial county (Yunlin County) and one reference county (Yilan County), which had no significant industrial activity that might emit pollutants, in Taiwan through analysis of 11 year long and publicly available data. Data from before and after the petrochemical company in the industrial county started (year 1999) operating were compared.

RESULTS

Residents of the industrialized county had lesser increases in life expectancy over time than did residents of a similar but less-industrialized county, with difference means ranging from 0.89 years (p<0.05) to 1.62 years (p<0.001) at different stages. Male residents were more vulnerable to the effects of industrialization. There were no significant differences in individual income between the two counties.

CONCLUSIONS

Countries, including Taiwan and the U.S., embracing petrochemical industries now face the challenge of environmental injustice. Our findings suggested that life expectancy lengthening was slowed and income growth was stalled for residents living in the industrial communities.

A review of the epidemiological methods used to investigate the health impacts of air pollution around major industrial areas

We performed a literature review to investigate how epidemiological studies have been used to assess the health consequences of living in the vicinity of industries. 77 papers on the chronic effects of air pollution around major industrial areas were reviewed. Major health themes were cancers (27 studies), morbidity (25 studies), mortality (7 studies), and birth outcome (7 studies). Only 3 studies investigated mental health. While studies were available from many different countries, a majority of papers came from the United Kingdom, Italy, and Spain. Several studies were motivated by concerns from the population or by previous observations of an overincidence of cases. Geographical ecological designs were largely used for studying cancer and mortality, including statistical designs to quantify a relationship between health indicators and exposure. Morbidity was frequently investigated through cross-sectional surveys on the respiratory health of children. Few multicenter studies were performed. In a majority of papers, exposed areas were defined based on the distance to the industry and were located from <2 km to >20 km from the plants. Improving the exposure assessment would be an asset to future studies. Criteria to include industries in multicenter studies should be defined.

Uneven magnitude of disparities in cancer risks from air toxics

This study examines race- and income-based disparities in cancer risks from air toxics in Cancer Alley, LA, USA. Risk estimates were obtained from the 2005 National Air Toxics Assessment and socioeconomic and race data from the 2005 American Community Survey, both at the census tract level. Disparities were assessed using spatially weighted ordinary least squares (OLS) regression and quantile regression (QR) for five major air toxics, each with cancer risk greater than 10⁻⁶. Spatial OLS results showed that disparities in cancer risks were significant: People in low-income tracts bore a cumulative risk 12% more than those in high-income tracts (p < 0.05), and those in black-dominant areas 16% more than in white-dominant areas (p < 0.01). Formaldehyde and benzene were the two largest contributors to the disparities. Contributions from emission sources to disparities varied by compound. Spatial QR analyses showed that magnitude of disparity became larger at the high end of exposure range, indicating worsened disparity in the poorest and most highly concentrated black areas. Cancer risk of air toxics not only disproportionately affects socioeconomically disadvantaged and racial minority communities, but there is a gradient effect within these groups with poorer and higher minority concentrated segments being more affected than their counterparts. Risk reduction strategies should target emission sources, risk driver chemicals, and especially the disadvantaged neighborhoods.

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.

Analysis of matched geographical areas to study potential links between environmental exposure to oil refineries and non-Hodgkin lymphoma mortality in Spain

Background

Emissions from refineries include a wide range of substances, such as chrome, lead, nickel, zinc, arsenic, cadmium, benzene, dioxins and furans, all of which are recognized by the International Agency for Research on Cancer (IARC) as carcinogens.

Various studies have shown an association between non-Hodgkin lymphoma (NHL) and residence in the vicinity of industrial areas; however, evidence of specific association between refineries and residence in the vicinity has been suggested but not yet established.

The aim of this study is to investigate potential links between environmental exposure to emissions from refineries and non-Hodgkin lymphoma mortality in Spain.

The spatial distribution of NHL in Spain has an unusual pattern with regions some showing higher risk than others.

Methods

We designed an analysis of matched geographical areas to examine non-Hodgkin lymphoma mortality in the vicinity of the 10 refineries sited in Spain over the period 1997-2006. Population exposure to refineries was estimated on the basis of distance from town of residence to the facility in a 10 km buffer.

We defined 10 km radius areas to perform the matching, accounting for population density, level of industrialization and socio-demographic factors of the area using principal components analysis.

For the matched towns we evaluated the risk of NHL mortality associated with residence in the vicinity of the refineries and with different regions using mixed Poisson models. Then we study the residuals to assess a possible risk trend with distance.

Results

Relative risks (RRs) associated with exposure showed similar values for women and for men, 1.09 (0.97-1.24) and 1.12 (0.99-1.27). RRs for two regions were statistically significant: Canary Islands showed an excess of risk of 1.35 (1.05-1.72) for women and 1.50 (1.18-1.92) for men, whilst Galicia showed an excess of risk of 1.35 (1.04-1.75) for men, but not significant excess for women.

Conclusions

The results suggest a possible increased risk of NHL mortality among populations residing in the vicinity of refineries; however, a potential distance trend has not been shown. Regional effects in the Canary Islands and Galicia are significantly greater than the regional average.

Cancer incidence in a petrochemical industry area in Sweden

Emissions from petrochemical industries may contain suspected or established carcinogens. As increased incidence of cancer in residential areas close to petrochemical industries has been reported in the literature, we conducted a study of cancer incidence in Stenungsund, Sweden, where petrochemical industries were established in the mid 1960s. A number of cancer cases in the central parts of Stenungsund were collected from the regional cancer registry for each year between 1974 and 2005. In addition to the total number of cases, the numbers of leukemia, lymphoma, liver cancer, lung cancer, and brain cancer were also collected. Expected numbers for each year were calculated based on age- and sex-specific incidence rates in reference areas. Levels of carcinogenic volatile hydrocarbons (VOC) were estimated from measurements and emission data. A dispersion model was used to classify Stenungsund into a "low" and "high" ethylene level area. Standardized Incidence Ratio (SIR) for all cancer for the entire period was 1.02 (95% CI 0.97-1.08). The occurrence of leukemia, lymphoma, and cancer in the central nervous system was slightly lower than expected for the entire period. SIR for lung cancer was 1.37 (95% CI 1.10-1.69), and SIR for liver cancer was 1.50 (0.82-2.53). VOC levels were low. Taking estimated exposure and demographic factors into account, our assessment is that occurrence of cancer was not affected by industrial emissions in any of the studied sites.