A report released to state officials on July 17 suggests there may be at least some reason for concern among residents living near the coal-burning Indian River Power Plant.
The report from the state’s Department of Public Health indicated that those living in a six ZIP-code area around the power plant — which is located on the Indian River, outside Dagsboro and Millsboro — have a higher overall rate of cancer when compared to Delawareans statewide and those living across the U.S. The rate per 100,000 people in the U.S. for cancer diagnosis is 473.6. In Delaware, that number is 501.3. In the Indian River zone, it is 553.9 — 17 percent higher than the national average.
Most concerning, the report notes a substantial increase particularly in lung cancer rates reported in the area that includes the towns of Dagsboro, Millsboro, Ocean View, Selbyville, Frankford and Georgetown and their environs. In fact, that increase in lung cancer accounts for nearly all of the overall cancer rate elevation when compared to statewide numbers.
“Lung cancer cases as a percentage of all cases are significantly higher in the Indian River ZIP codes (19.5 percent) than Delaware (15.0 percent),” the report notes. In contrast, “Breast cancer cases as a percentage of all cases are higher in Delaware (16.8 percent) than in the Indian River ZIP codes (14.1 percent).” Other cancers, such as ovarian cancer, have roughly the same rate of occurrence, or less, in the Indian River area as statewide.
The report came after pressure from cancer groups and environmental activists brought Lt. Gov. John Carney to ask DPH to preliminarily study whether there was a real basis for public concern about the impact of the notoriously polluting coal-fired power plant on residents’ health.
That pressure had been heightened recently through the public input process regarding the state’s future power supply, which included and ended in a recommendation for a proposed wind farm off the coast of the Indian River Inlet — a solution deemed far more environmentally friendly than even the proposed coal-gasification design proposed for a new Indian River generator by operator NRG.
“The request was made because of future power plant options and concerns about cancer resulting from the current coal-burning facility,” the report notes.
Residents have for years pointed to the existing coal-burning power plant as a source of concern, many even rejecting — in favor of the proposed wind farm — the so-called “clean coal” upgrade that was proposed to join the existing plant and potentially become the first plant in the nation to “sequester” carbon dioxide emissions below ground.
Using figures from 1994 to 2004, DPH researchers determined that 771 residents of the Indian River area had been diagnosed with lung and bronchus cancers, of 6,509 statewide. Of all cancer diagnoses in Delaware, 15 percent were lung cancer, while in the Indian River area that number was 19.5 percent — a 28 percent higher rate of diagnosis among all cancer diagnoses.
Report not a definitive diagnosis of problem
Despite those stark numbers, DPH researchers did not label the report as a definitive link between the power plant and cancer in residents who live near it.
“The literature shows some evidence that exposure to particulates may cause cancer. However, evidence that coal-burning power plants specifically cause cancer is not clear,” DPH stated in the second paragraph, before introducing the potentially alarming figures regarding cancer incidence.
“This analysis has significant limitations,” it also warns. “No adjustments were made for other potentially relevant factors, such as smoking incidence, socio-economic status, or access to health care. In addition, exposure or dose data was not available or considered.
The DPH report also suggests but does not fully address the possibility that the area’s growing population of retirees might have swayed the figures toward a higher incidence rate for lung cancer — generally diagnosed later in life — rather than clearly indicating a true cancer cluster among the area’s long-term population.
“Cancer cases did not occur at a younger age in Indian River as compared to Delaware,” the report notes. “For Indian River, 10.8 percent of the cases occurred below the age of 51 years, compared to 16.2 percent of cancer cases in Delaware.”
The report takes pains to point out that a disproportionate number of the residents in the studied area around the power plant had moved into the area recently, compared with numbers statewide.
“With respect to length of residency, in 2000, 21.9 percent of Indian River residents had moved into the area from a different county, state or country. This is compared to 16.3 percent of the Delaware residents who had moved from a different state or country,” it said.
Further, the report also notes that the cancer incidence figures had not taken into account a variety of causational factors that might have resulted in the cluster of lung cancer cases.
“No adjustments were made for other potentially relevant factors, such as smoking incidence, socio-economic status, or access to health care,” the report noted. “In addition, exposure or dose data was not available or considered.
“Tobacco use is a hypothesis that should be further explored to explain the higher rate of lung cancer cases in Indian River than in the state, and possibly for the higher rate of cancer overall,” the report suggests. “This is because cigarette smoking causes about 85 percent of all lung cancer. Data on tobacco use in this area and for these cases would be required to explore this hypothesis further, but is not available.”
However, a June 2007 report on the state’s health indicated that, county-wide, Sussex County residents diagnosed with cancer had similar smoking habits as state-wide. Some 18.7 percent had smoked at the time of their diagnosis, compared to 18.8 percent statewide, 18.4 percent in New Castle County and 20.5 percent in Kent County. The percentage of non-smokers with cancer was not a telling number in the survey, being similar across all counties.
Sussex County also showed up in the middle range of the survey of cancer patients in whether smokers diagnosed with cancer had smoked starting before the age of 18. Kent County smokers again led those numbers. Passive smoking exposure in Sussex was generally less for the cancer patients than the statewide average. Lung cancer patients statewide were, naturally, significantly more likely to have been smokers.
Beyond suggesting that a “hypothesis” regarding tobacco use in the Indian River cluster area be investigated, the report notes only a lack of information regarding that and other possible complicating factors to the raw numbers of cancer cases in the area around the power plant.
Indeed, the report essentially looks at some very basic information about cancer diagnoses in the six ZIP codes and makes the comparison to the same numbers state- and nationwide: type of cancer, age and location. The numbers, on the surface, suggest a cancer cluster at Indian River, but the researchers took pains in their report to say they lacked much of the detailed information that would definitively indicate the power plant as a cause for the increased incidence of lung cancer in area residents.
“In addition to tobacco use and migration unknowns, no information about actual exposure to environmental carcinogens is available to study as part of this investigation,” they wrote. “It is not known if the prevailing winds would deposit respirable particulates in the Indian River community or if such particles would be carried east out to the ocean. Air quality studies in the Indian River area are not available to compare with what is known in other areas of the state.
“Further, since lung cancer usually results from exposures that occurred decades ago, measurements of environmental conditions today may not reflect conditions relevant to recent cancer rates,” the researchers added.
Other pollutants pose risk to area residents
While addressing concerns about lung cancer related to inhaling pollutants from the power plant, DPH researchers also pointed out another common concern related to its impact on health: mercury poisoning the area’s waters and food chain.
“In addition, some of the contaminants from the power plan (e.g. mercury) would not necessarily have the greatest impact in a plume touchdown area, based on air modeling,” they said. “The biologically-relevant human exposures to mercury occur predominantly from oral ingestion of contaminated fish flesh, which has been converted to a methylated form and concentrated in the food chain, not direct inhalation of air.”
In 2003 alone, the power plant was found to have released 395 pounds of mercury. Exposure to high levels of mercury is known to cause damage to the brain and kidneys, and to developing fetuses. Women who are pregnant or nursing, as well as young children, are advised to severely limit consumption of fish more likely to be contaminated with mercury for just that reason.
A 2006 summary of mercury results in Delaware fish samples from 2003, 2004 and 2005 noted that mercury was detected in all samples. The mercury criterion had been exceeded in large bluefish caught offshore, though not in smaller bluefish caught in Delaware Bay or Indian River Inlet. And mercury in fish described as “big tuna” had been found at six times the Delaware criterion and nearly twice the Food and Drug Administration (FDA) Action Level.
Also of concern in the food chain are polychlorinated biphenyls (PCBs), which are no longer produced in the U.S. but which are still found in the environment and are believed to be a risk to the liver and to fetuses and young children.
Due to PCBs and mercury contamination, Delaware currently recommends that large bluefish (14 inches or larger) taken from Delaware waters — both in the Atlantic and the Inland Bays, including Indian River — not be consumed by vulnerable populations and be limited to no more than one meal per year by healthy adults. Smaller bluefish are recommended to be eaten no more often than once a month. Statewide, officials recommend no one eat more than one meal per week of any fish caught in Delaware waters or off its coast, due to a variety of contaminants. (A meal is considered to be an 8-ounce serving for an adult, a 3-ounce serving for a child.)
The Citizens for Clean Power, which was one of the groups pushing for the cancer study, also asked the state in 2006 to look into the health impact of other pollutants coming from the power plant. “CCP believes it would be prudent to conduct studies to investigate the possibility of nitrate and heavy metal contamination around the Indian River site and the extent of mercury poising in humans and fish in the area,” the group told the state’s Air Quality Management Section in April of 2006.
New research could add to limited data, but will it happen?
So, is there a cancer cluster near the Indian River Power Plant?
“By definition, a cancer cluster occurs when a statistically higher rate of cancer exists in a defined community as compared to the region as a whole. The higher rate of cancer — lung cancer in particular — in the Indian River area is a cancer cluster,” researchers spelled out, but with caveats that have left area residents no less concerned.
“A review of 10 years of cancer data did not identify a disproportionate number of cancer cases among young people in Indian River,” the report concludes. “It also did not identify a cluster of unusual cancers or cancers with a known, rare cause. The absence of any abnormalities such as these provides no clues as to the origin of this cluster and suggests that further investigation is unlikely to be fruitful.”
Addressing what should be done about the issue now that a cancer cluster has been identified — if not definitively in its cause — the DPH praised new rules from the state’s Department of Natural Resources and Environmental Control (DNREC) that were designed to reduce emissions from coal-burning power plants.
“Regardless of the unknowns regarding the causal relationship between power plant emissions and cancer, both generally and in Indian River in particular, these rules are a major step forward in providing a clean environment,” the report states.
DPH’s recommendations also emphasized, “This investigation has reached the limits of evaluation with available data,” and suggested that consideration be given to locating DNREC air-quality monitors in the Indian River area and to studying deposition patterns to garner more information about potential exposures to carcinogens and small particulates – things the report said could prove useful for monitoring the effectiveness of the new emission control rules.
DPH also recommended consideration of epidemiologic studies using new data from lung cancer patients or their survivors in Indian River, as well as from a control group. “Especially valuable would be information about tobacco use and residence history,” the report said.
But residents of the area of the power plant and this now-identified cancer cluster were left to wait this week and see whether such studies will even be done. DPH cautioned in its report, “The potential benefit of such studies must be weighed against the diversion of resources from other cancer control efforts. For this reason, the Division recommends that the Environmental Committee of the Delaware Cancer Consortium consider whether such studies should be done.”
Carney, who sits on the advisory board to the Delaware Cancer Consortium, was initially non-committal on whether such a study should be pursued, but he has since said he would support further research.
The DCC’s Environmental Committee has rescheduled a meeting originally set for Aug. 6, and is now set to meet at noon on Monday, Aug. 13, to discuss whether to fund additional research on the cancer cluster. The meeting will be held at DNREC Air & Waste Management Office, in Conference Room B, at 391 Lukens Drive in New Castle.
Residents of the area around the Indian River Power Plant were heard to grumble about the meeting’s location as news of the report and cancer cluster spread this week, since those most affected are, on a practical basis, least likely to be able to attend. The Coastal Point will follow up with news from this meeting, as well as any further information available on the cancer cluster and efforts to control pollution from the Indian River power plant.