Self-Reported Cancer Rates in Two Rural Areas of West Virginia with and Without Mountaintop Coal Mining

Adult asthma associated with roadway density and housing in rural Appalachia: the Mountain Air Project (MAP)

BACKGROUND

Appalachian Kentucky is a rural area with a high prevalence of asthma among adults. The relative contribution of environmental exposures in the etiology of adult asthma in these populations has been understudied.

OBJECTIVE

This manuscript describes the aims, study design, methods, and characteristics of participants for the Mountain Air Project (MAP), and focuses on associations between small area environmental exposures, including roadways and mining operations, and lifetime and current asthma in adults.

METHODS

A cohort of residents, aged 21 and older, in two Kentucky counties, was enrolled in a community-based, cross-sectional study. Stratified cluster sampling was used to select small geographic areas denoted as 14-digit USGS hydrologic units (HUCs). Households were enumerated within selected HUCs. Community health workers collected in-person interviews. The proximity of nearby active and inactive coal mining operations, density of oil and gas operations, and density of roadways were characterized for all HUCs. Poisson regression analyses were used to estimate adjusted prevalence ratios.

RESULTS

From 1,459 eligible households contacted, 1,190 individuals were recruited, and 972 persons completed the interviews. The prevalence of lifetime asthma was 22.8%; current asthma was 16.3%. Adjusting for covariates, roadway density was positively associated with current asthma in the second (aPR = 1.61; 95% CI 1.04-2.48) and third tertiles (aPR = 2.00; 95% CI 1.32-3.03). Increased risk of current asthma was associated with residence in public, multi-unit housing (aPR = 2.01; 95% CI 1.27-3.18) compared to a residence in a single-family home. There were no notable associations between proximity to coal mining and oil and gas operations and asthma prevalence.

CONCLUSIONS

This study suggests that residents in rural areas with higher roadway density and those residing in public housing units may be at increased risk for current asthma after accounting for other known risk factors. Confirming the role of traffic-related particulates in producing high asthma risk among adults in this study contributes to the understanding of the multiple environmental exposures that influence respiratory health in the Appalachia region.

Increased Dementia Mortality in West Virginia Counties with Mountaintop Removal Mining?

Atmospheric particulate matter (PM) is elevated in areas of mountaintop removal mining (MTM), a practice that has been ongoing in some counties of West Virginia (WV) USA since the 1970s. PM inhalation has been linked to central nervous system pathophysiology, including cognitive decline and dementia. Here we compared county dementia mortality statistics in MTM vs. non-MTM WV counties over a period spanning 2001–2015. We found significantly elevated age-adjusted vascular or unspecified dementia mortality/100,000 population in WV MTM counties where, after adjusting for socioeconomic variables, dementia mortality was 15.60 (±3.14 Standard Error of the Mean (S.E.M.)) times higher than that of non-MTM counties. Further analyses with satellite imaging data revealed a highly significant positive correlation between the number of distinct mining sites vs. both mean and cumulative vascular and unspecified dementia mortality over the 15 year period. This was in contrast to finding only a weak relationship between dementia mortality rates and the overall square kilometers mined. No effect of living in an MTM county was found for the rate of Alzheimer’s type dementia and possible reasons for this are considered. Based on these results, and the current literature, we hypothesize that inhalation of PM associated with MTM contributes to dementia mortality of the vascular or unspecified types. However, limitations inherent in ecological-type studies such as this, preclude definitive extrapolation to individuals in MTM-counties at this time. We hope these findings will inspire follow-up cohort and case-controlled type studies to determine if specific causative factors associated with living near MTM can be identified. Given the need for caregiving and medical support, increased dementia mortality of the magnitude seen here could, unfortunately, place great demands upon MTM county public health resources in the future.

Intrastate Variations in Rural Cancer Risk and Incidence: An Illinois Case Study

CONTEXT

Although rural-urban cancer disparities have been explored with some depth, disparities within seemingly homogeneous rural areas have received limited attention. However, exploration of intrarural cancer incidence may have important public health implications for risk assessment, cancer control, and resource allocation.

OBJECTIVE

The objective of this study was to explore intrastate rural cancer risk and incidence differences within Illinois.

DESIGN

Illinois's 83 rural counties were categorized into northern, central, and southern regions (IL-N, IL-C, and IL-S, respectively). Chi-square test for independence and analysis of variance calculations were performed to assess regional differences in demographic characteristics, socioeconomic deprivation, smoking history, obesity, cancer-screening adherence, and density of general practitioners. Age-adjusted incidence rates were calculated for 5 cancer categories: all cancers combined, lung, colorectal, breast (female), and prostate cancers. Unadjusted and adjusted incidence rate ratios (IRRs) were calculated to evaluate regional differences in rates for each cancer category.

RESULTS

Socioeconomic deprivation varied by region: 4.5%, 6.9%, and 40.6% of IL-N, IL-C, and IL-S counties, respectively (P < .001). Smoking history also significantly differed by region. Mean former/current smoking prevalence in IL-N, IL-C, and IL-S counties was 46.4%, 48.2%, and 51.4%, respectively (P = .006). In unadjusted analysis, IL-C (IRR = 1.12; 95% confidence interval [CI], 1.02-1.23) and IL-S (IRR = 1.24; 95% CI, 1.13-1.35) had increased lung cancer incidence compared with IL-N. Elevated risk remained in IL-S after adjusting for relevant factors such as smoking and socioeconomic deprivation (IRR = 1.14; 95% CI, 1.04-1.26).

CONCLUSIONS

Socioeconomic deprivation, health behaviors, and lung cancer incidence varied across rural regions. Our findings underscore the importance of identifying cancer risk heterogeneity, even within a state, to effectively target risk factor reduction and cancer control interventions.

Mountaintop Removal Coal Mining and Emergent Cases of Psychological Disorder in Kentucky

Although mountaintop removal (MTR) coal extraction techniques have been employed in Appalachia for decades, relatively little research has examined its potential psychological impact on people living in close proximity to MTR activity. The current study taps the State Emergency Department Database (Healthcare Cost and Utilization Project, Kentucky State Emergency Department Database, 2008) to examine the relative risk for diagnoses of depressive, substance use, and anxiety disorders originating in areas with and without MTR activity. Logistical regression analyses, controlling for ethnicity, rurality, mean income, and gender, indicated that MTR independently predicts greater risk for depressive (OR 1.37) and substance use disorders (OR 1.41), but not anxiety disorders. Overall, these findings have public health policy implications, build on other evidence of increased risk of negative mental health outcomes related to MTR, and lend some support to the validity of solastalgia related to environmental change.

Systematic review of community health impacts of mountaintop removal mining

BACKGROUND

The objective of this evaluation is to understand the human health impacts of mountaintop removal (MTR) mining, the major method of coal mining in and around Central Appalachia. MTR mining impacts the air, water, and soil and raises concerns about potential adverse health effects in neighboring communities; exposures associated with MTR mining include particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), metals, hydrogen sulfide, and other recognized harmful substances.

METHODS

A systematic review was conducted of published studies of MTR mining and community health, occupational studies of MTR mining, and any available animal and in vitro experimental studies investigating the effects of exposures to MTR-mining-related chemical mixtures. Six databases (Embase, PsycINFO, PubMed, Scopus, Toxline, and Web of Science) were searched with customized terms, and no restrictions on publication year or language, through October 27, 2016. The eligibility criteria included all human population studies and animal models of human health, direct and indirect measures of MTR-mining exposure, any health-related effect or change in physiological response, and any study design type. Risk of bias was assessed for observational and experimental studies using an approach developed by the National Toxicology Program (NTP) Office of Health Assessment and Translation (OHAT). To provide context for these health effects, a summary of the exposure literature is included that focuses on describing findings for outdoor air, indoor air, and drinking water.

RESULTS

From a literature search capturing 3088 studies, 33 human studies (29 community, four occupational), four experimental studies (two in rat, one in vitro and in mice, one in C. elegans), and 58 MTR mining exposure studies were identified. A number of health findings were reported in observational human studies, including cardiopulmonary effects, mortality, and birth defects. However, concerns for risk of bias were identified, especially with respect to exposure characterization, accounting for confounding variables (such as socioeconomic status), and methods used to assess health outcomes. Typically, exposure was assessed by proximity of residence or hospital to coal mining or production level at the county level. In addition, assessing the consistency of findings was challenging because separate publications likely included overlapping case and comparison groups. For example, 11 studies of mortality were conducted with most reporting higher rates associated with coal mining, but many of these relied on the same national datasets and were unable to consider individual-level contributors to mortality such as poor socioeconomic status or smoking. Two studies of adult rats reported impaired microvascular and cardiac mitochondrial function after intratracheal exposure to PM from MTR-mining sites. Exposures associated with MTR mining included reports of PM levels that sometimes exceeded Environmental Protection Agency (EPA) standards; higher levels of dust, trace metals, hydrogen sulfide gas; and a report of increased public drinking water violations.

DISCUSSION

This systematic review could not reach conclusions on community health effects of MTR mining because of the strong potential for bias in the current body of human literature. Improved characterization of exposures by future community health studies and further study of the effects of MTR mining chemical mixtures in experimental models will be critical to determining health risks of MTR mining to communities. Without such work, uncertainty will remain regarding the impact of these practices on the health of the people who breathe the air and drink the water affected by MTR mining.

Manuscript title: Geospatial analysis of Cancer risk and residential proximity to coal mines in Illinois

BACKGROUND

Studies have indicated a population-level association between coal mining and cancer incidence and mortality, but few studies specifically examined residential proximity to this exposure using spatial analysis. We utilized a Geographic Information Systems (GIS) approach to perform spatial and statistical analyses to test two coal mining exposure variables and their associations with cancer incidence and mortality in Illinois--the fourth highest coal producing state in the United States.

METHODS

Data included age-adjusted county-level cancer incidence and mortality for five cancers: all malignant, lung, colorectal, breast (female) and prostate. Coal mining exposure was defined by two variables: coal production group and distance-weighted exposure. Spatial analyses were performed to identify spatial clustering. Correlation and stepwise regression analyses were performed to explore the relationship between cancer incidence and mortality and coal mining exposures. Covariates considered in regression analyses included socioeconomic deprivation, former/current smoking prevalence, race, and rurality.

RESULTS

Global spatial autocorrelation indicated significant spatial clustering of incidence, mortality and aggregated coal production. Distance-weighted exposure was significantly correlated with coal production group, age-adjusted all cancer incidence and age-adjusted all cancer mortality. Regression analyses indicated an association between recent coal production and colorectal cancer incidence (p=0.009) and mortality (p=0.035) and prostate cancer mortality (p=0.047). Distance weighted exposure was associated with lung cancer incidence (p=0.004) and mortality (p<0.001), and all cancer mortality (p<0.001).

CONCLUSION

Coal production, incidence and mortality are spatially clustered in Illinois. Exposures to coal mining were associated with elevated risk of multiple cancers, most notably lung and colorectal. The environmental impact of the mining industry is substantial, and exposure of individuals residing near coal mines to known carcinogens is plausible. Future studies are needed to further elucidate the population exposure dynamics of coal mining, and should be explored using individual-level exposures and cancer outcomes.

Atmospheric particulate matter in proximity to mountaintop coal mines: sources and potential environmental and human health impacts

Mountaintop removal mining (MTM) is a widely used approach to surface coal mining in the US Appalachian region whereby large volumes of coal overburden are excavated using explosives, removed, and transferred to nearby drainages below MTM operations. To investigate the air quality impact of MTM, the geochemical characteristics of atmospheric particulate matter (PM) from five surface mining sites in south central West Virginia, USA, and five in-state study control sites having only underground coal mining or no coal mining whatsoever were determined and compared. Epidemiologic studies show increased rates of cancer, respiratory disease, cardiovascular disease, and overall mortality in Appalachian surface mining areas compared to Appalachian non-mining areas. In the present study, 24-h coarse (>2.5 µm) and fine (≤2.5 µm) PM samples were collected from two surface mining sites in June 2011 showed pronounced enrichment in elements having a crustal affinity (Ga, Al, Ge, Rb, La, Ce) contributed by local sources, relative to controls. Follow-up sampling in August 2011 lacked this enrichment, suggesting that PM input from local sources is intermittent. Using passive samplers, dry deposition total PM elemental fluxes calculated for three surface mining sites over multi-day intervals between May and August 2012 were 5.8 ± 1.5 times higher for crustal elements than at controls. Scanning microscopy of 2,249 particles showed that primary aluminosilicate PM was prevalent at surface mining sites compared to secondary PM at controls. Additional testing is needed to establish any link between input of lithogenic PM and disease rates in the study area.

Appalachian mountaintop mining particulate matter induces neoplastic transformation of human bronchial epithelial cells and promotes tumor formation

Epidemiological studies suggest that living near mountaintop coal mining (MTM) activities is one of the contributing factors for high lung cancer incidence. The purpose of this study was to investigate the long-term carcinogenic potential of MTM particulate matter (PMMTM) exposure on human bronchial epithelial cells. Our results show that chronic exposure (3 months) to noncytotoxic, physiological relevant concentration (1 μg/mL) of PMMTM, but not control particle PMCON, induced neoplastic transformation, accelerated cell proliferation, and enhanced cell migration of the exposed lung cells. Xenograft transplantation of the PMMTM-exposed cells in mice caused no apparent tumor formation, but promoted tumor growth of human lung carcinoma H460 cells, suggesting the tumor-promoting effect of PMMTM. Chronic exposure to the main inorganic chemical constituent of PMMTM, molybdenum but not silica, similarly induced cell transformation and tumor promotion, suggesting the contribution of molybdenum, at least in part, in the PMMTM effects. These results provide new evidence for the carcinogenic potential of PMMTM and support further risk assessment and implementation of exposure control for PMMTM.

An examination of the effects of mountaintop removal coal mining on respiratory symptoms and COPD using propensity scores

Previous research on public health consequences of mountaintop removal (MTR) coal mining has been limited by the observational nature of the data. The current study used propensity scores, a method designed to overcome this limitation, to draw more confident causal inferences about mining effects on respiratory health using non-experimental data. These data come from a health survey of 682 adults residing in two rural areas of Virginia, USA characterized by the presence or absence of MTR mining. Persons with a history of occupational exposure as coal miners were excluded. Nine covariates including age, sex, current and former smoking, overweight, obesity, high school education, college education, and exposure to coal as a home-heating source were selected to estimate propensity scores. Propensity scores were tested for balance and then used as weights to create quasi-experimental exposed and unexposed groups. Results indicated that persons in the mountaintop mining group had significantly (p < 0.0001) elevated prevalence of respiratory symptoms and chronic obstructive pulmonary disease. The results suggest that impaired respiratory health results from exposure to MTR environments and not from other risks.

Atmospheric particulate matter size distribution and concentration in West Virginia coal mining and non-mining areas

People who live in Appalachian areas where coal mining is prominent have increased health problems compared with people in non-mining areas of Appalachia. Coal mines and related mining activities result in the production of atmospheric particulate matter (PM) that is associated with human health effects. There is a gap in research regarding particle size concentration and distribution to determine respiratory dose around coal mining and non-mining areas. Mass- and number-based size distributions were determined with an Aerodynamic Particle Size and Scanning Mobility Particle Sizer to calculate lung deposition around mining and non-mining areas of West Virginia. Particle number concentrations and deposited lung dose were significantly greater around mining areas compared with non-mining areas, demonstrating elevated risks to humans. The greater dose was correlated with elevated disease rates in the West Virginia mining areas. Number concentrations in the mining areas were comparable to a previously documented urban area where number concentration was associated with respiratory and cardiovascular disease.

Population cancer risks associated with coal mining: a systematic review

Background

Coal is produced across 25 states and provides 42% of US energy. With production expected to increase 7.6% by 2035, proximate populations remain at risk of exposure to carcinogenic coal products such as silica dust and organic compounds. It is unclear if population exposure is associated with increased risk, or even which cancers have been studied in this regard.

Methods

We performed a systematic review of English-language manuscripts published since 1980 to determine if coal mining exposure was associated with increased cancer risk (incidence and mortality).

Results

Of 34 studies identified, 27 studied coal mining as an occupational exposure (coal miner cohort or as a retrospective risk factor) but only seven explored health effects in surrounding populations. Overall, risk assessments were reported for 20 cancer site categories, but their results and frequency varied considerably. Incidence and mortality risk assessments were: negative (no increase) for 12 sites; positive for 1 site; and discordant for 7 sites (e.g. lung, gastric). However, 10 sites had only a single study reporting incidence risk (4 sites had none), and 11 sites had only a single study reporting mortality risk (2 sites had none). The ecological study data were particularly meager, reporting assessments for only 9 sites. While mortality assessments were reported for each, 6 had only a single report and only 2 sites had reported incidence assessments.

Conclusions

The reported assessments are too meager, and at times contradictory, to make definitive conclusions about population cancer risk due to coal mining. However, the preponderance of this and other data support many of Hill’s criteria for causation. The paucity of data regarding population exposure and risk, the widespread geographical extent of coal mining activity, and the continuing importance of coal for US energy, warrant further studies of population exposure and risk.

Personal and family health in rural areas of Kentucky with and without mountaintop coal mining

PURPOSE

This study investigates health disparities for adults residing in a mountaintop coal mining area of Appalachian Kentucky. Mountaintop mining areas are characterized by severe economic disadvantage and by mining-related environmental hazards.

METHODS

A community-based participatory research study was implemented to collect information from residents on health conditions and symptoms for themselves and other household members in a rural mountaintop mining area compared to a rural nonmining area of eastern Kentucky. A door-to-door health interview collected data from 952 adults. Data were analyzed using prevalence rate ratio models.

FINDINGS

Adjusting for covariates, significantly poorer health conditions were observed in the mountaintop mining community on: self-rated health status, illness symptoms across multiple organ systems, lifetime and current asthma, chronic obstructive pulmonary disease, and hypertension. Respondents in mountaintop mining communities were also significantly more likely to report that household members had experienced serious illness, or had died from cancer in the past 5 years. Significant differences were not observed for self-reported cancer, angina, or stroke, although differences in cardiovascular symptoms and household cancer were reported.

CONCLUSIONS

Efforts to reduce longstanding health problems in Appalachia must focus on mountaintop mining portions of the region, and should seek to eliminate socioeconomic and environmental disparities.