A research study published in the scientific journal Ecohealth found links between stream quality, coal mining intensity, and cancer rates in West Virginia. This peer-reviewed study is a smoking gun connecting water pollution in mining areas to adverse human health outcomes.
There is no question that mining activities impair water quality. For example, Massey Energy has amassed thousands of Clean Water Act violations related to their mining operations in the past few years alone. There is also no doubt that mining discharge, runoff, and waste in streams destroys fish and other life in these aquatic ecosystems. However, few previously studies have directly examined the relationship between water pollution and human health in the coal fields. This study by Nathaniel Hitt, an aquatic biologist now working for the U.S. Geological Survey (bio sketch), and Michael Hendryx, a community health researcher at West Virginia University (bio sketch), helps fill that gap.
The researchers examined indices of surface water quality, mining activity, health status, socioeconomic status, and demographic variables for the entire state of West Virginia.
Water quality was measured using the West Virginia Stream Condition Index (SCI). The SCI is a composite measure developed by the West Virginia Department of Environmental Protection to assess water quality of all major streams in the state, with samples taken every five years.
The SCI is an indicator of ecosystem health and can identify impairment with respect to the reference (or natural) condition. The index includes six biological attributes, called metrics, that represent elements of the structure and function of the bottom-dwelling macroinvertebrate assemblage. Metrics are specific measures of diversity, composition, and tolerance to pollution, that include ecological information.
The SCI is to be used as the basis for bioassessment in West Virginia and has been calibrated for a long-term biological index period extending from April through October. A data analysis application has been developed to ensure consistency in data management and analysis throughout the state as DEP biologists conduct biological monitoring.
WV Department of Environmental Protection
Cancer outcome data were drawn from the Centers for Disease Control and Prevention cancer mortality surveillance protocol for each county in West Virginia.
Data collected by local cancer registries enable public health professionals to understand and address the cancer burden more effectively. CDC provides support for states and territories to maintain registries that provide high-quality data.
Information on residence of cancer victims permits evaluation of spatial clustering of cases.
In addition to demographic and socioeconomic status data, the CDC surveillance programs also collects information on tobacco use and other behavioral health markers such as substance abuse and obesity.
The primary findings of the study are as follows:
Regression and spatial analyses revealed significant associations between ecological integrity and public health. SCI was negatively related to age-adjusted total cancer mortality per 100,000 people. Respiratory, digestive, urinary, and breast cancer rates increased with ecological disintegrity, but genital and oral cancer rates did not. Smoking, poverty, and urbanization were significantly related to total cancer mortality, but did not explain the observed relationships between ecological integrity and cancer. Coal mining was significantly associated with ecological disintegrity and higher cancer mortality. Spatial analyses also revealed cancer clusters that corresponded to areas of high coal mining intensity. Our results demonstrated significant relationships between ecological integrity and human cancer mortality in West Virginia, and suggested important effects of coal mining on ecological communities and public health. Assessments of ecological integrity therefore may contribute not only to monitoring goals for aquatic life, but also may provide valuable insights for human health and safety.
EcoHealth, April, 2010
The authors have discussed the significance of this research in media interviews.
"We've known for years that stream organisms can be sentinels of environmental quality," said study co-author Nathaniel Hitt, a Virginia Tech stream ecologist who now works for the U.S. Geological Survey. "What we have now shown is that these organisms are also indicators of public health."
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"We found that cancer rates are linked to environmental quality even after accounting for other major risks such as smoking," Hendryx said. "Furthermore, we saw that the most impaired streams were in close proximity to coal surface mines. This adds to the body of evidence that coal mining is harmful to ecosystems and human health."
Charleston Gazette article by Ken Ward Jr.
The West Virginia Coal Association and other industry lobbying groups will almost certainly attack this study as they did with a previous study published by Hendryx. Let me explain why their attacks will be without substance or merit.
- The measures of water quality and cancer mortality are standardized, of high quality, and collected by independent sources, eliminating most common sources of bias.
- The investigators have expertise and experience in handling water quality and health quality data.
- The relationship between water quality and cancer is likely to be underestimated by the study. Many of the contaminants in mining waste and discharge are heavy metals such as arsenic, mercury, cadmium, and selenium. The lag between initial exposure, cancer onset, and mortality is typically 10-20 years. Because of the rapid expansion of mountaintop removal mining in the past decade, cancer morbidity and mortality in the region associated with toxic exposures will grow exponentially in the coming years. What is captured in this study is the initial stages of this process.
- The mining industry likes to pretend that other industries impair water quality in West Virginia. There are only three other major source points for water pollution in the state - coal fired power plants, coal processing facilities, and chemical manufacturing plants. The chemical industries are clustered in the so-called "chemical alliance zone" around Charleston. Mining activities in this region are low and chemical manufacturing cannot account for spatial analyses looking at cancer clustering proximal to mining. I strongly recommend that the investigators conduct secondary analyses excluding the chemical alliance zone and examine proximity to coal-fired power plants in anticipation of attacks on the study from the coal industry.
- The relationship between water pollution, mining activities, and cancer is biologically plausible. Mining-related water pollution involves heavy metals. Heavy metals are associated with increased risk of lung, digestive, and urinary tract cancer, subtypes verified in the secondary analyses.
- Cancer mortality is likely to be greater in poor rural areas because of limited access to medical care. However, including population density and socioeconomic status in the models did not eliminate the association.
- The researchers were able to control for tobacco use and other common behavioral risk factors for cancer.
- Mining activities also impair air quality as well as water quality. This possibility can be tested simply by introducing water quality into spatial analysis of cancer clustering related to mining activity. A strong residual effect of mining with water quality in the model would argue that water quality is not the only or primary vector in cancer risk.
This study is really a starting point for linking human health outcomes to coal mining activities. Hendryx has also collaborated on several other studies looking at the relationship between mining and human health, including the seminal study published in the journal Science on mountaintop removal mining in January of 2010. The next steps will require the identification of the mechanisms underlying pollution from coal mining and the health of those living in the region.
"Regulation of coal mining is often portrayed as a choice between 'mayflies and miners'," said Emily Bernhardt, a Duke University biologist who has researched mining issues and testified on behalf of citizen groups. "However, this study shows how streams are important for the health and welfare of miners and their communities."
Charleston Gazette article by Ken Ward Jr.
The blather and hype about "clean coal" refers to gasification and carbon sequestration to limit heat trapping emissions into the atmosphere. However, the life cycle costs and negative impacts of coal from extraction and combustion residuals in the waste stream cannot be overlooked. Coal will never be clean. It will never be anything other than a destructive 19th Century energy source that demonstrates the profound ignorance and carelessness of human beings in managing the resources of this planet.