PUBLIC HEALTH ASSESSMENT
US DOE PORTSMOUTH GASEOUS DIFFUSION PLANT
PIKETON, PIKE COUNTY, OHIO
A three-part approach is used to assess the public health implications associated with a site. First, ATSDR addresses the toxicological implications in a discussion of health effects that might occur in people exposed to specific contaminants. Second, state and local health databases are evaluated for evidence that such health effects have occurred. And finally, the agency addresses the community's concerns about site-related health issues. ATSDR staff members believe that all three approaches are important for the eventual identification of site-specific public health problems.
Introduction
A release of a hazardous waste does not always result in exposure. People are exposed to a contaminant such as those identified in the PORTS Site only if they come in contact with it; they might be exposed by breathing, eating, or drinking a substance containing the contaminant or by skin contact with a substance containing the contaminant. Several factors determine the type and severity of health effects associated with exposure to a contaminant. Such factors include the exposure concentration (how much); the frequency and/or duration of exposure (how long); the route of exposure (breathing, eating, drinking, or skin contact); and the multiplicity of exposure (combination of contaminants). Moreover, people can be exposed to an environmental contaminant by more than one route of exposure. Once exposure takes place, characteristics such as age, sex, nutritional status, genetics, lifestyle, and health status of the exposed individual influence how the individual absorbs, distributes, metabolizes, and excretes the contaminant. Together, those factors and characteristics determine the health effects that might result from exposure to a contaminant.
ATSDR considers physical and biologic characteristics when developing health guidelines. Toxicological profiles prepared by ATSDR representatives summarize chemical-specific toxicologic and adverse health effects information. Health guidelines, such as ATSDR's minimal risk level (MRL) and EPA's reference dose (RfD) and cancer slope factor (CSF) are included in the toxicological profiles. Those guidelines are used by ATSDR public health professionals to determine an individual's potential for developing adverse non-cancer health effects and/or cancer from exposure to a hazardous substance.
Health guidelines provide a basis for comparing estimated exposures with concentrations of contaminants in different environmental media (soil, air, water, and food) depending on the characteristics of the people who might be exposed and the length of the exposure. An MRL is defined as an estimate of the daily human exposure to a contaminant that is likely to be without an appreciable risk of adverse non-cancer health effects over a specified duration of exposure (acute, <15 days; intermediate, 15-365 days; chronic, > 365 days). Oral MRLs are expressed in units of milligrams per kilogram per day (mg/kg/day). MRLs are not derived for dermal exposure. The method for deriving MRLs does not include information about cancer; therefore, an MRL does not imply anything about the presence, absence, or level of cancer risk. An EPA RfD is an estimate of the daily exposure of the human population, including sensitive subpopulations, that is likely to be without appreciable risk of adverse non-cancer health effects during a lifetime (70 years). Non-cancer health guidelines are adjusted downward using uncertainty factors to make them adequately protective of the public health. Therefore, the health guidelines should not be viewed as strict scientific boundaries between what level is toxic and what level is nontoxic. For cancer-causing substances, EPA has established the CSF as a health guideline. The CSF is used to estimate the number of excess cancers maximally expected from exposure to a contaminant.
To link a site's human exposure potential with health effects that might occur under site-specific conditions, ATSDR representatives estimate human exposure to site contaminants from ingestion and/or inhalation of different environmental media. The following relationship is used to determine the estimated exposure to the site contaminant:
ED = (C x IR x EF) / BW
ED = exposure dose (mg/kg/day)
C = contaminant concentration
IR = intake rate
EF = exposure factor
BW = body weight
ATSDR uses standard intake rates for ingestion of water and soil. The intake rate for drinking water is 2 liters per day (L/day) for adults and 1 L/day for children. For incidental ingestion of soil, the intake rate is 100 mg/day for adults, 200 mg/day for children, and 5,000 mg/day for children with pica behavior (repeated ingestion of non-nutritive substances). Standard body weights for adults and children are 70 kg and 10 kg, respectively. The maximum contaminant concentration detected in a specific medium at a site is used to determine the estimated exposure; use of the maximum concentration results in an evaluation that is most protective of human health. When unknown, the biological absorption from environmental media (soil, water, etc.) is assumed to be 100%.
People might be exposed to more than one contaminant from the PORTS Site. Data on the health effects of exposure to multiple contaminants are very limited. Those effects can be additive, synergistic (greater than the sum of the single contaminant exposures), or antagonistic (less than the sum of the single contaminant exposures). Also, simultaneous exposure to contaminants that are known or probable human carcinogens could increase the risk of developing cancer. In most cases, there is insufficient information about the effect of mixtures of contaminants. ATSDR's evaluation of exposures in this public health assessment is limited to individual contaminant exposures; multiple exposures have not been evaluated.
Hydrogen fluoride was measured as a weekly average of total fluorides. Adverse health effects from the concentrations of hydrogen fluoride (HF) that could have reached the public off-site are unlikely. ATSDR has set a provisional guidance value for average air concentration at 10 µg/m3 , which is unlikely to cause any adverse human health effect [23]. This value is more than 100 times below the level that caused mild irritation to the noses and eyes of human volunteers exposed 10 days [24]. The maximum HF concentration reported in ambient air off site was 3.48 µg/m3 in March 1988.
Trichloroethylene (TCE)
There were no historical or current completed pathways for TCE exposure from PORTS. The most likely exposures to TCE would have been to workers at the plant.
No adverse effects could have come from this chemical because there is no pathway by which the public could be exposed to uranium hexafluoride (UF6). This chemical is so reactive with water that any UF6 that could have escaped into the air would have been ultimately hydrolyzed or decomposed to hydrogen fluoride gas and uranium oxides [25].
Levels of exposure to uranium from the PORTS facility are significantly below the levels known to cause measurable health effects.
Uranium acts primarily as a renal toxin; it damages the kidneys and inhibits the body's ability to remove wastes from the bloodstream. Although ATSDR found no completed pathway for uranium oxide, we verified that the rates for renal failure related deaths, in the counties around PORTS, are not elevated in comparison to US or State of Ohio rates (see Table 11 on the following page).
B. Health Outcome Data Evaluation
The Centers for Disease Control and Prevention (CDC), National Center for Health Statistics, Office of Analysis and Epidemiology compiles mortality data for the entire U.S. population on its WONDER (Wide-ranging ONline Data for Epidemiologic Research) database for the years 1979 to 1991. A detailed look at all causes of death for Pike, Ross, and Scioto counties in Ohio shows significantly higher rates of cardiovascular disease for Pike County, and Scioto County appears to have a slightly higher mortality rate from cancer. However, when the data is age-adjusted for the population, the cancer rate falls in line with the rest of the state. Age-adjusting health outcome data is necessary to compare one county to another, because older subpopulations have higher rates of cancer and cardiovascular mortality. Age-adjusting modifies the crude mortality rate to what it would be if the population were of standard age distribution.
Table 11. Age-Adjusted Mortality Rates by County for the Years 1979 to 1991
| Cause of Death | United States | State of Ohio | Pike | Ross | Scioto |
| Renal Failure | 8.3 | 8.4 | 6.4 | 8.8 | 8.8 |
| Cardiovascular Disease | 223.9 | 238.2 | 311.8 | 270.5 | 281.4 |
| All Cancers | 198.4 | 210.0 | 181.5 | 188.9 | 215.0 |
| Lung Cancer | 56.4 | 56.7 | 58.7 | 50.9 | 63.0 |
| Brain Cancer | 4.3 | 4.3 | 4.1U | 3.8U | 4.8U |
| Childhood Cancers (to 14 years of age) |
4.0 | 4.1 | 8.3U | 2.1U | 5.3U |
| Prostate Cancer (males) | 27.9 | 28.9 | 22.1 | 23.9 | 28.5 |
| Breast Cancer (females) | 28.7 | 31.1 | 12.9 | 28.4 | 30.0 |
| Notes: 1. All Rates are per 100,000 persons. 2. "U" designates a statistically insignificant sample. Source: Compressed Mortality Data File, 1979-1991; CDC, National Center for Health Statistics, Office of Analysis and Epidemiology, WONDER Database |
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The age-adjusted rate for childhood cancer mortality in Pike County is roughly twice the national and state rates, but the number was too small to give a statistically reliable result. This rate is based on only 5 cancer deaths for the 13-year period from 1979 to 1991. None of the childhood cancers were of the same type and therefore could not be related to a common cause.
If there were significant uranium exposure in the community surrounding the plant, a measurable increase in the rate of renal failure would be expected. No increase in the renal failure rate was identified in surrounding communities. No other trends were found for the area for the years 1979 to 1991. Table 11 shows rates for selected causes of death for the counties surrounding Piketon and is referenced to the national and state rates for those causes.
The EPA's epidemiological database U.S. Cancer Mortality Rates and Trends for 1950-1979 shows that Pike County, Ohio, experienced higher incidence of cancer mortality (>73rd percentile) for the following causes, when compared to the state of Ohio and the United States: oral and tongue cancer; kidney, bladder, and brain cancer. EPA's mortality data has not been age-adjusted, and this lack of adjustment could account for the apparent higher rates of cancer mortality.
The Ohio Department of Health also compiles and publishes an annual report of vital statistics. Even though EPA's compiled data show certain types of cancer were elevated when compared to the rest of the state of Ohio, the Ohio Health Department report shows no real deviation from state norms. However, the death rate from heart disease is significantly higher than state and national averages and has continued to increase for the last 25 years.
A National Cancer Institute (NCI) study of cancer mortality around U.S. nuclear facilities was reported as showing "no evidence that an excess occurrence of cancer has resulted from living near nuclear facilities" (Consensus Statement of the Ad Hoc Advisory Committee in Jablon et al. 1990) [27].
Among the facilities examined in this report was the Portsmouth Gaseous Diffusion plant (PORTS). Relative risks for a number of types of cancer all clustered around one, providing little evidence for increased cancer mortality.
The NCI study examined cancer mortality during the years 1950-1984 in counties with and without nuclear facilities. Three "control counties" were matched to each study county based on certain factors, including race, education, mean family income, region, and urban/rural. For Pike County (the location of PORTS) the control counties were Vinton, Meigs, and Gallia, all in Ohio. Scioto County, approximately 2.5 miles south of PORTS was not included in the study. Cancer mortality for sixteen classes of tumors was analyzed by age group, calendar year, gender, and race. After standardization of the mortality data, comparisons were made of: Pike Co. vs. control counties and before vs. after operation of the facility. Mortality before operation was estimated from 1950-1954 data (PORTS opened in 1952 and began operations in 1954). Standardized mortality ratios (SMR) were used for these comparisons. The SMR is the ratio of the observed numbers of cases to the expected numbers of cases (expectations were based on U.S. statistics). Relative risks were in turn estimated by dividing the SMR for Pike County by the SMR in comparison counties.
For all ages combined, the relative risks in Pike Co. vs. control counties (both after operation) ranged from 0.37 (thyroid) to 1.56 for primary liver cancer. While some higher relative risks were observed for certain age groups, these were typically based on very small numbers, making the estimates unstable. Unfortunately, confidence intervals were not computed; instead we are merely told whether a relative risk was statistically significant (a few) or not (most) [28].
This study has a number of limitations, many discussed in Jablon et al. (1990). These limitations include:
Pike County vital statistics were provided to Boston University by the Vital Statistics Registrar for the Pike County Ohio, Board of Health. All cancer and some non-cancer causes of death are compiled in the table below.
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Pike County:
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| Cause of Death: | 1991 | 1992 | 1993 |
|
Cancers Total |
18 | 28 | 27 |
| Lung Cancer | 5 | 8 | 7 |
| Breast Cancer | 5 | 5 | 5 |
| Brain Cancer | 2 | 2 | 1 |
| Colon Cancer | 0 | 2 | 2 |
| Pancreatic Cancer | 2 | 1 | 1 |
|
Unknown Cancer |
1 | 2 | 3 |
| Gastric Cancer | 0 | 1 | 1 |
| Kidney Cancer | 1 | 1 | 1 |
| Liver Cancer | 0 | 1 | 0 |
| Prostate Cancer | 1 | 1 | 3 |
| Rectal Cancer | 1 | 1 | 0 |
| Skin Cancer | 1 | 1 | 0 |
|
Stomach Cancer |
0 | 1 | 0 |
| Cervical Cancer | 0 | 0 | 1 |
| Laryngeal Cancer | 0 | 0 | 2 |
| COPD/Resp./Pulmonary | 21 | 24 | 5 |
|
Emphysema |
0 | 1 | 0 |
| Renal Failure | 0 | 0 | 3 |
| Certificates of Service | 11 | 3 | 7 |
| Total Deaths | 210 | 177 | 182 |
"Certificates of Service" are deaths occurring out of state where the deceased is buried in Pike County. These deaths are not broken down in the vital statistics by the cause of death. Based on the 1990 census population of Pike County (24,249 people), crude rates (per 100,000) and 95% confidence intervals were estimated for total cancers for 1991, 1992, and 1993: 74.2 (CI 56.7 - 91.7), 115 (CI 93.3 - 137), 111 (89.9 - 133). Despite large confidence intervals, these crude rates show an increased cancer death rate in Pike County from 1991 to 1992. Without age-adjusted rates, however, no inference can be made, and the crude rates are not comparable to the age-specific state rates.
Additionally, many of the same problems highlighted in the review of the NCI study are applicable to any use of these data: mortality is a weak indicator for more curable cancers, and a county level analysis necessarily dilutes any possible cancer outcomes found near PORTS.
In the first section of the report ("Death certificate analysis of cancer mortality in Ohio, 1986 - 1988"), age-adjusted rates are computed by direct standardization using the 1980 U.S. Census Population and eighteen, 5-year age groupings. Twenty-one cancer categories were evaluated.
Actual rates were given in the ODH report, and Boston University staff, under a cooperative agreement with ATSDR, calculated a rate ratio (RR) for Pike County and all abutting counties by comparing county rates to the Ohio rate. The cancer outcomes evaluated are based on documented community concerns. All rates are age-adjusted. Boston University staff also performed an analysis of four cancer outcomes for Pike and Scioto Counties using other ODH data in Section 4.
Table 12, on the following page, shows age-adjusted rates for each cancer of concern for Pike and the surrounding six counties and for Ohio (presented in the "cancer" column). The ratio of the rate for each county to the rate for Ohio is presented in parenthesis under the county rates.
Table 12. Cancer Mortality Rates for Ohio Counties 1986 - 1988 (per 100,000)
| Cancer Ohio Rate |
Pike | Scioto | Adams | Highland | Ross | Vinton | Jackson |
| All cancer 207.50 |
170.74* (0.82) |
218.01** (1.05) |
199.81 (0.96) |
181.78* (0.88) |
181.81* (0.88) |
188.36 (0.91) |
192.29* (0.93) |
| Brain 5.06 |
NA | 3.84 (0.76) |
7.08 (1.40) |
3.83 (0.76) |
2.49* (0.49) |
NA | NA |
| Breast women 32.83 |
NA | 26.64 (0.81) |
24.82 (0.76) |
23.91 (0.73) |
27.93 (0.85) |
NA | 20.15 (0.61) |
| Colorectal 25.50 |
12.86* (0.50) |
26.15 (1.03) |
26.64 (1.04) |
24.26 (0.95) |
26.55 (1.04) |
20.59 (0.81) |
18.85* (0.74) |
| Leukemia 7.61 |
7.41 (0.97) |
7.84 (1.03) |
8.91 (1.17) |
7.08 (0.93) |
6.84 (0.90) |
13.18 (1.73) |
7.72 (1.01) |
| Liver 3.29 |
NA | 3.47 (1.05) |
NA | NA | NA | NA | NA |
| Lung 57.90 |
60.26 (1.04) |
66.96** (1.16) |
58.87 (1.02) |
48.08* (0.83) |
50.12* (0.87) |
57.34 (0.99) |
58.86 (1.02) |
| Lymphoma 11.41 |
9.07 (0.79) |
10.17 (0.89) |
5.80* (0.51) |
6.98* (0.61) |
6.99* (0.61) |
NA | 9.42 (0.83) |
| Pancreatic 9.39 |
11.04 (1.18) |
11.61** (1.24) |
5.73* (0.61) |
9.79 (1.04) |
10.04 (1.07) |
13.82 (1.47) |
6.14* (0.65) |
| Prostate 31.46 |
16.24* (0.52) |
29.31 (0.93) |
NA | 33.06 (1.05) |
26.53 (0.84) |
NA | 19.42* (0.62) |
| Renal 3.98 |
5.29 (1.33) |
4.30 (1.08) |
NA | 6.54 (1.64) |
3.79 (0.95) |
NA | 6.58** (1.65) |
| Skin 3.32 |
7.87* (2.37) |
3.94 (1.19) |
NA | NA | 2.72 (0.82) |
NA | NA |
| Stomach 5.40 |
6.90 (1.28) |
4.09* (0.76) |
8.07 (1.49) |
NA | 3.20* (0.59) |
13.43** (2.49) |
5.57 (1.03) |
| * - indicates the county
rate is significantly lower than the state rate. ** - indicates the county rate is significantly higher than the state rate. NA - indicates a rate was not calculated. The number of deaths was less than five and these rates would be highly unstable. |
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Those rate ratios (RR) which are greater than 1.50 are based on very few deaths (less than 10) in a county. Despite large 95% confidence intervals (CI), three of the counties had rates that were statistically larger than the state rates:
| Cancer Ohio Rates | County Rates |
| Leukemia:7.61 (CI: 7.46-7.76) Renal:3.98 (CI: 3.87-4.09) Skin:3.32 (CI: 3.22-3.41) Stomach:5.40 (CI: 5.28-5.52) |
Vinton = 13.18 (CI: 7.29-19.1) Highland = 6.54 (CI: 2.18-8.91) Jackson = 6.58 (CI: 4.09-9.07)* Pike = 7.87 (CI: 4.66-11.1)* Vinton = 13.43 (CI: 7.42-19.4)* |
| * - indicates the county rate is significantly higher than the state rate. | |
For those cancers that appear elevated in Pike County, confidence intervals are estimated for the county and state rates to determine statistical power. Of the following four cancers, only skin cancer is statistically elevated in Pike County relative to Ohio. However, colorectal cancer, prostate cancer, and total cancer mortality rates were each significantly below the state rates.
| Cancer Ohio Rates | Pike County Rates |
| Lung:57.9 (CI: 57.5-58.3) Pancreatic:9.39 (CI: 9.23-9.55) Stomach:5.40 (CI: 5.28-5.52) Skin:3.32 (CI: 3.22-3.41) |
60.3 (CI: 51.7-68.8) 11.0 (CI: 7.36-14.7) 6.90 (CI: 4.08-9.72) 7.87 (CI: 4.66-11.1)* |
| * - indicates the county rate is significantly higher than the state rate. | |
Scioto County cancer rates found to be elevated include total cancers, lung, and pancreatic cancer:
| Cancer Ohio Rates | Scioto County Rates |
| All cancer:207.50 (CI: 206.72-208.28) Lung:57.9 (CI: 57.5-58.3) Pancreatic:9.39 (CI: 9.23-9.55) |
218.01 (CI: 209.58-226.44)* 66.96 (CI: 62.2-71.7)* 11.61 (CI: 10.1-13.1)* |
| * - indicates the county rate is significantly higher than the state rate. | |
Because renal cancer RR's are based on limited deaths, they appear elevated in three of five counties, but have a statistically stable elevation in only one county (Jackson). Given the concern with uranium exposure from PORTS, increases in renal cancer are noteworthy. For Scioto County, statistically elevated rates for lung cancer death also noted. Lung cancer is another potential outcome of concern at nuclear sites.
These data indicate that there were 4 deaths from brain cancer in Pike County from 1986 - 1988, which is in agreement with local community. According to newspaper accounts, this point was disputed by ODH in the past.
4. Ohio Cancer Mortality Data for 1987 to 1992 from ODH
In addition to the ODH Report "Cancer Mortality Rates in Ohio, 1986 - 88" evaluated in Section 3, Boston University staff also received a data print-out for 1987 to 1992. The data print-out summarized Ohio county-level and statewide crude and age-adjusted mortality rates, by gender, for several specific types of cancer. The method of computing mortality rates was different in the two reports, so the data were not comparable.
Based on this ODH 1987 - 1992 data, four cancers of interest in the counties around PORTS are summarized in the following table. Both counties had lung cancer rates that exceeded the state rate, and the results for the other cancers of interest were mixed. No bone, brain, or leukemia cancer mortality rate was statistically different from the state rates for these cancers. The one instance where the county rate is dramatically different from the state rate is Pike County bone cancer mortality. This rate is based on one (1) death due to bone cancer in the county over these six years and is statistically unreliable. Similarly, the county rates for brain and leukemia cancer deaths are based on fairly small numbers and are also unstable. Cancer rates are presented with relative rates below in parentheses:
County to State Relative Rates:
| Cancer | Pike County | Scioto County |
| Lung Cancer Bone Cancer Brain Cancer Leukemia |
(1.12) (3.27) (0.68) (0.95) |
(1.15) (0.42) (0.90) (1.25) |
5. Ohio Department of Health Data Availability
Ohio does not keep a separate birth defects registry. However, ODH does have data compiled from birth certificates, including the number of children born with defects. From death certificates, ODH compiles infant mortality information. These data are available as counts by county. Data are not available for individuals, so risk factors can not be analyzed. There is cancer registry information, begun in 1987, but it only covers Cuyahoga County, Lake Geauga County, parts of Medina County, Toledo, and Massilon (not Pike or surrounding counties). The Ohio Department of Health has begun a population-based cancer incidence reporting system for the state of Ohio: The Ohio Cancer Incidence Surveillance System (OCISS). The OCISS presently covers parts of Cuyahoga County only and does not include Pike County or surrounding counties.
6. NIOSH Study "Mortality Among Uranium enrichment Workers" January 1987
This study was based on deaths up to the close of 1982 and involved a cohort of 5,773 PORTS past and present workers who had worked at the plant for a week or more after the plant started operations in September 1954. This study reaches no definitive conclusion and recommends the study be updated in future years based on some of the weaknesses resulting from the limited latency period evaluated.
Most of the weaknesses in this study resulted from the time at which it was conducted, but additional weaknesses were found:
NIOSH is currently working on an update of this study, which is to include an evaluation of exposure to electromagnetic fields (EMFs) from powerlines and equipment. Contact with NIOSH indicates that no results are yet available.
7. Comprehensive Epidemiologic Data Resource (CEDR)
Comprehensive Epidemiologic Data Resource (CEDR) by U.S. Department of Energy, Assistant Secretary for Environment, Safety and Health (August, 1993)(3):
The CEDR program provides a repository of DOE data that have been used to support epidemiologic studies. Most of the epidemiologic studies have been published in peer-reviewed journals; however, there are also data that have been used in student dissertations, presentations, and DOE technical reports. The number, type, and format of variables included in studies vary considerably. The studies represent entirely different groups of people or cohorts. Data in the CEDR files pertain to approximately 420,000 individuals employed at one or more of 50 DOE sites or facilities. (U.S.DOE, 1993)
There are 24 data sets available in CEDR as of 1994 - none pertain specifically to the Portsmouth Gaseous Diffusion Facility. However, NIOSH completed a worker study in 1987, the results of which are discussed above, in Section 6.
Residents living near PORTS completed a cancer survey (1994) for the area surrounding the facility. They went door-to-door collecting cancer prevalence data from people at each residence for 1) people residing at that residence, 2) people living nearby with cancer, and 3) people who had recently moved away and had cancer. The survey was performed by volunteers in the group, and they were not able to contact everyone. They report finding 247 cancer cases within an approximately six-mile radius of PORTS, including areas of Pike, Scioto, Jackson, and Adams Counties. The majority of the cancers reported were from areas in Pike County. The following cancers were reported in the survey:
| Bone | 6 | Lung | 10 |
| Brain Tumor | 21 | Lymph node | 4 |
| Breast | 29 | Pancreas | 3 |
| Cervical/Uterine | 7 | Prostate | 2 |
| Colon | 19 | Skin | 5 |
| Hodgkin's | 3 | Stomach | 6 |
| Kidney | 3 | Throat | 7 |
| Leukemia | 9 | Thyroid | 12 |
| Liver | 4 | Unidentified Cancers | 95 |
| TOTAL | 245 |
As with Ohio Department of Health cancer mortality data, the data collected do not contain information on age, length of residence in the area, smoking status, occupational exposures, or other risk factors. These diagnoses have not been confirmed by any medical records. Additionally, there was no information on the type the cancer in 95 of the cases reported. These limitations make it difficult to generate meaningful cancer rates from these data. The residents noted that they found 21 brain tumors. However, tumors are not distinguished from malignant cancers.
Boston University staff, while compiling community concerns, also compiled anecdotal community health information. This information overlaps somewhat with the community cancer survey, but also includes non-cancer health effects experienced in the community. While this information is not usable for the estimation of rates, it is a first step in identifying health outcomes of concern in a population. In the case of the community around PORTS, initial anecdotal health effects strongly indicated past fluoride exposures in the community, although no significant source of fluorides could be identified.
10. Health Practitioners Anecdotal Data
Boston University staff contacted health practitioners who were reported to have noticed excess health outcomes in the community around PORTS or to possess possible sources of health outcome data.
11. Neurofibromatosis 1, NF-1, or vonRecklinghausen's Disease
Symptoms observed by ATSDR medical staff, among some community members appeared consistent with Neurofibromatosis 1. NF-1 is an autosomal dominant genetic disorder. The gene mutation occurs on chromosome 17 (while the rarer NF-2 mutations occur on chromosome 22). The mechanism of this genetic disorder is presently the focus of research. Most sources concurred that approximately half of the cases of NF-1 result from spontaneous mutation. Rate information found for NF-1 ranged from 1/3000 to 1/4000 throughout the literature reviewed(4). All sources concurred that there were approximately 100,000 cases in the U.S. (0.04% prevalence) at present. Rates reportedly do not vary between males and females (Gold, 1989), but researchers believe more information is needed to adequately evaluate non-Caucasian expression of the disease. No information was identified indicating rate differences geographically or based on any specific risk factors.
C. Community Health Concerns Evaluation
Concerns were collected from site visits, public meetings, public availability sessions, newspaper articles, letters from residents, and phone calls and meetings with residents. When several people expressed the same or similar health concerns, they have been combined. Care has been taken to maintain the original intention of concerns in the combined comments. Non-health concerns are listed, but not addressed in Appendix A.
This summary is divided into two main sections. The outline of sections and subsections is as follows:
A. Past exposures related to the site
Releases from the 1978 cylinder rupture did not get to off-site locations at levels high enough to result in adverse health effects. Also, uranium and hydrogen fluoride have not been linked in any studies to the types of cancer listed above.
Information available does not indicate the burning of spent fuel rods on-site. There is no indication that fuel rods were ever handled on-site.
Plutonium was never worked with at the PORTS facility.
ATSDR reviewed all incident reports for the PORTS facility, and found no reports of air releases that could adversely affect the health of off-site residents.
The well referred to showed a false hit for technetium. When the water sample was retested, technetium was not detected. The first test of the water sample showed technetium just at the lower limit of detection, and was most likely detecting natural radon.
The purpose of the health consultation was to investigate the abnormally high airborne fluorides erroneously printed in the 1986 environmental report. Releases for other years were evaluated as part of the public health assessment.
ATSDR believes there is some confusion with a Massachusetts Nutritional Study at the Fernald School (reported in the national news services) of iron uptake. There is no indication that PORTS conducted any human radiation experiments.
Exposures to workers in enclosed spaces has not been linked to any environmental exposures to the general public.
B. Continuing exposure concerns related to the site
ATSDR uses all available sources of environmental sampling data, from DOE, USGS, Ohio EPA, US EPA and the public. Health outcome data is taken from Ohio Department of Health, Centers for Disease Control and Prevention, local health officials and practitioners. The data is reviewed for accuracy and relevancy before referencing in ATSDR documents.
ATSDR's Public Health Assessment for the Portsmouth Gaseous Diffusion Plant, looks at materials used at the site, environmental releases and adverse health outcomes in the areas surrounding the site to identify the need for further public health actions.
The DOE and US EPA hold regular public meetings and have asked for public comment and input on their environmental programs. ATSDR does not routinely perform its own sampling and relies mainly on existing environmental sampling data.
Air:
Steam from the site's heat exchangers, is just water vapor and poses no health risk to the public.
Under the Superfund Amendments and Reauthorization Act of 1986 (SARA), the site is required to notify the Community Emergency Coordinator for the local emergency planning committee and describe the materials released, the time an duration of release, medium or media into which the release occurred, any known or anticipated acute or chronic health risks associated with the emergency and any advice regarding medical attention necessary for exposed individuals. For the Portsmouth Gaseous Diffusion Plant, the Community Emergency Coordinator is currently Mr. Don Simonton of the Pike County Emergency Planning Board. The site has emergency warning sirens around the plant that are triggered when a release above the emergency criteria for that material. Releases inside the plant enclosures do not generally result in releases to the environment and would not trigger a siren, but would be reported to authorities. If a siren goes off, you can call the Pike County Emergency Management Agency at (614) 947-7346, to get detailed information about the emergency.
PORTS does not emit any substance that matches this description. There are several pulp and paper plants up wind from the site that could be the source of the sulfurous smells. Also, many trees emit a clear to dark amber colored sticky sap from Spring through the late Summer.
Site staff have reported being called to check on this material and have reported that it was pine pollen. Most likely it is tree pollen. It is natural and not toxic.
Because air samples indicate averages that are over a factor of 1000 below comparison values, there is no indication that levels exceed any health related concentrations.
ATSDR has reviewed documentation on materials used and stored at the PORTS site and found that none of them contained radium. The Uranium used at PORTS is all in the chemical form of Uranium Hexafluoride. There are no decay products left when this is produced, and therefore no radium. Radon is a decay product of radium and that means that the PORTS site is not giving off radon gas from the stored UF6.
The radon in homes around the site is only due to accumulation of natural radon gas, percolating up from the ground. Though high concentrations of radon have been associated with lung cancer in uranium miners, there has been no demonstrated case of household radon causing lung cancer. Even so, ATSDR encourages you to have the living spaces in your home monitored for radon, and to follow EPA's guidelines for reducing household radon levels. (EPA's screening level for radon is 4 pCi/liter of air in living spaces)
The level of fluorides being emitted by PORTS, poses no health risk to the surrounding community.
It is not plausible that this damage could be caused by HF, because HF is too water soluble to reach the deep lung. Chronic lung disease can be caused by a number of factors; the most common cause is smoking of tobacco products. The temperature inversions that are common in the Ohio River Valley tend to accumulate and concentrate air pollutants from all sources, including industrial and automobile emissions. It is not possible to link any one cause to the respiratory impairment without a medical evaluation by a competent specialist and is generally not possible even with such an evaluation.
ATSDR evaluated all materials released from the PORTS Plant, and found none being released at levels of health concern.
Yes, ATSDR specifically considered temperature inversions in its analysis.
Soil:
PORTS does not emit arsenic. Arsenic is commonly used in pesticides for fruit trees.
ATSDR considers contamination from other sites only when it impacts the exposure levels of the population being evaluated, and in this specific case will not be addressing the above site in this public health assessment.
ATSDR evaluated information on waste landfilled at PORTS for this PHA.
Surface Water:
PORTS releases to the streams do not appear to be hazardous, but access to streams on-site is restricted for security reasons.
No, Ohio EPA has evaluated the local surfacewater streams and their fish. Both reports referenced in the public health assessment failed to find contamination above any comparison value. Ohio EPA's Technical Report EAS/1993-5-2 concludes that local fish do not show significant evidence of contamination from PORTS.
Ohio EPA has evaluated PORTS impact on surfacewater streams and fish in Ohio EPA's Technical Report EAS/1993-5-2 concluding that local fish do not show significant evidence of contamination from PORTS.
Biota:
Because of the large number of residences that directly discharge raw sewage into the streams, it is probably advisable to contact the Ohio EPA concerning current health recommendations or advisories.
Ohio EPA's Technical Report EAS/1993-5-2 concludes that local fish do not show significant evidence of contamination from PORTS.
Ohio EPA has tested the surface water streams on-site, reported in OEPA Technical Report EAS/1993-5-2 and found no significant contamination. ATSDR found no evidence of contamination off-site that could get in any food pathway at levels of health concern.
Ground Water:
With the active groundwater pumping and treatment ongoing at the facility, there should not be any off-site migration.
As discussed previously, contamination from PORTS does not appear to be migrating off-site, and therefore ATSDR recommends residents contact the Pike County Water Authority at: (614) 289-4568, whenever their water smells like sewage.
Background groundwater samples include a number of private residential wells and the municipal well fields for Piketon and surrounding communities.
Off-site residential well samples have not shown any contamination from the site.
PORTS has not contaminated any off-site wells. However, there is indication that numerous residents are using shallow private wells that are located too close to their septic tank field lines, resulting in high fecal coliform bacteria. This is a cause of severe diarrhea and can be very dangerous to infants, because of the risk of severe dehydration.
Again, PORTS has not contaminated any off-site wells, but due to the depth and placement of shallow private wells, there may be contamination from personal waste disposal practices.
PORTS does not release fluorides into the groundwater. Fluorides occur naturally in some groundwater and can be above safe levels for safe drinking.
Other:
There are no known adverse health effects from exposure to ultra-low frequency electromagnetic fields put out by power lines. The National Academy of Sciences has recently stated that they found no relationship between the electromagnetic fields and adverse health effects, after reviewing over 500 studies [29].
ATSDR has evaluated all known chemicals released from the plant and has not found evidence of any exposures at levels of health concern.
ATSDR looked at release information from all manufacturing facilities in the area, in its evaluation. Table 8 lists other manufacturers in Pike County, Ohio.
Because ATSDR does not have the authority to address worker's health concerns, the following worker related concerns have been referred to the National Institute for Occupational Safety and Health (NIOSH).
ATSDR is aware of the limitations of using mortality and has also contacted local public health professionals to help evaluate the health of this community. ATSDR's Public Health Assessment for the Portsmouth Gaseous Diffusion Plant, is a first screening, to determine the need for further public health activities.
Multi-site studies are used when there are confirmed exposures to a substance, but the total number of individuals exposed is small. Around PORTS, there were exposures to the public that could cause adverse health effects. No exposed individuals of the public were identified around PORTS, therefore ATSDR will not perform a multi-site study.
ATSDR has compared Pike and Scioto Counties to surrounding counties, the State of Ohio and the United States rates for health outcome data, in the "Health Outcome Data Evaluation" section.
EPA's Riggans tapes are limited by the lack of quality control. They have not been checked for validity and there is no age adjustment. Without age adjustment, it is not possible to compare one locality to another.
ATSDR has not been able to identify any releases from the PORTS plant from 1958 to the present, at a level that could cause acute or chronic sickness. ATSDR reviewed EPA data, as well as DOE environmental data including classified documents, to determine the full range of site releases into air, water and soil.
ATSDR also reviewed all available health outcome data, looking for health effects that could be caused by chemicals and materials used on the site. As stated in the previous section titled Health Outcome Data Evaluation beginning on page 33, there were no identified illnesses that could be related to any site releases or materials used on site.
Spotting of tooth enamel could possibly be caused by smoking stains or by excessive prenatal and early childhood exposure to high levels of hydrogen fluoride (HF), in water supplies, while teeth are forming below the gum-line. The plant's air releases of hydrogen fluoride would not have caused the spotty discolorations on teeth.
The described conditions could be consistent with chemical burns but would occur only with acute dermal exposure to very high levels of HF or other acids. Dermal exposure to HF at levels high enough to cause the reported condition would have to be on the order of 3 mg/m3. This is roughly 1,000 times higher than concentrations measured off site.
It is not plausible that this damage could be caused by HF, because HF is too water soluble to reach the deep lung. Chronic lung disease can be caused by a number of factors; the most common cause is smoking of tobacco products. The temperature inversions that are common in the Ohio River Valley tend to accumulate and concentrate air pollutants from all sources, including industrial and automobile emissions. It is not possible to link any one cause to the respiratory impairment without a medical evaluation by a competent specialist and is generally not possible even with such an evaluation.
Residents were concerned that the condition could be chloracne, which can be caused by exposures to chlorine and fluorine compounds (e.g., HF). It would be unlikely for the condition to occur from the environmental concentrations of these materials. The people would need to be in close contact with high concentrations of such materials if they were to develop chloracne. These lumps could also be cysts or boils or other diseases to include neurofibromatosis Type 1 (NF1). (See concern #8.)
Therapeutic doses of fluoride would be necessary to embrittle bones. The off-site concentrations of HF would be unlikely to cause this condition.
Residents express concern that the state's cancer rates for Pike County don't include people who lived in Pike County but died elsewhere. Residents commented that Pike County hasn't had a good hospital to treat people, so people have gone other places (including Texas; Portsmouth and Cincinnati, Ohio; and Kentucky) for treatment. Is the data ATSDR uses reported by place of death or place of residence? Does ATSDR control for these missing data in its assessment? Why won't ATSDR do a complete health study and find the records of these people?
The Centers for Disease Control and Prevention (CDC), National Center for Health Statistics, Office of Analysis and Epidemiology compiles mortality data for the entire U.S. population on its WONDER (Wide-ranging ONline Data for Epidemiologic Research) database for the years 1979 to 1991. A detailed look at all causes of death for Pike, Ross, and Scioto counties in Ohio show significantly higher rates of cardiovascular disease for Pike County, and Scioto County appears to have a slightly higher mortality rate from cancer. However, when the data is age-adjusted for the population, the cancer rate falls in line with the rest of the state. Age-adjusting health outcome data is necessary to compare one county to another, because older subpopulations have higher rates of cancer and cardiovascular mortality. Age-adjusting modifies the crude mortality rate to what it would be if the population were of standard age distribution.
The crude rate for all cancer mortality was elevated for Scioto County, but this was because of the higher percentage of older residents. When the rate was age-corrected, using census data, the rate was not significantly different from those of other Ohio counties or from the national average.
The age-adjusted rate for childhood cancer mortality in Pike County is roughly twice the national and state rates but is not statistically significant. This rate is based on only 5 cancer mortalities for the 13-year period from 1979 to 1991. None of the childhood cancers were of the same type and therefore could not be related to a common cause.
NF1 is a common genetic disease with an incidence of 1 in 3,000 [30]. NF1 is also the most common cause of childhood cancers. NF1 can cause cafe-au-lait macules, axillary freckling, neurofibromas, Lisch nodules, learning disabilities, and a number of related cancers. The gene that transmits the genetic disease NF1 is Mandelevian dominant, which means that if you have the gene you will also have the disease. Also, if a one parent has the disease, roughly 25% of that parent's children will inherit the gene and, therefore the disease.
The following table (Table 13),was obtained from the March of Dimes and lists the national average occurrence of various types of birth defects. The types of birth defects that were brought up by community members are fairly common. Ear-folds are not a birth defect and are related to fetal position in the mother's womb. Webbed fingers and toes are genetically linked and therefore tend to run in families. Neither of these conditions is life threatening, and both can be corrected with plastic surgery. Syndactyly is the medical term for webbing between adjacent fingers or toes. This condition can involve nervous, vascular, bone and connective tissues. Syndactyly occurs in approximately 1 out of 2,500 births and is more prevalent in males. [31]
Table 13. Frequency of Selected Adverse Pregnancy Outcomes in Humans*
| EVENT | FREQUENCY PER 100 | UNIT |
| Spontaneous abortion, 8-28 weeks | 10-20 | Pregnancies or women |
| Chromosomal anomalies in spontaneous abortions, 8-28 weeks | 30-40 | Spontaneous abortions |
| Chromosomal anomalies identified by amniocentesis | 2 | Amniocentesis specimens |
| Stillbirths | 2-4 | Stillbirths and livebirths |
| Low birthweight <2.5 kg | 7 | Livebirths |
| Major Malformations | 2-3 | Livebirths |
| Chromosomal anomalies | 0.2 | Livebirths |
| Severe mental retardation | 0.4 | Children to 15 years of age |
| * Modified from National Foundation March of Dimes: Report of Panel II. Guidelines for reproductive studies in exposed human populations. In Bloom, A.D. (ed.): Guidelines for Studies of Human Populations Exposed to Mutagenic and Reproductive Hazards. The Foundation, New York, 1981, pp. 37-110. | ||
An incident involving a cylinder of uranium hexafluoride (UF6) that was dropped and ruptured on March 7, 1978, was the only such incident of a magnitude to warrant further health concern, since the plant opened. Only those in the immediate vicinity of the cylinder (on site) would have had any risk of adverse health effects. Uranium hexafluoride is a solid below 56ºC(133ºF) and some of the material would have reacted with water vapor in air to form hydrogen Fluoride (HF). This HF would have been a health hazard, only to those in the immediate vicinity of the ruptured cylinder. HF is further discussed in the Toxicological Evaluation section on page 31.
ATSDR representatives have forwarded these concerns to their counterparts in the National Institute for Occupational Safety and Health (NIOSH) within CDC. The Superfund legislation does not grant ATSDR any power to make recommendations concerning worker health and safety, because that is already the responsibility of NIOSH in the Public Health Service.
Surface streams at PORTS do not appear to be any threat to public health. ATSDR reviewed EPA's RCRA data for the local surface water streams, as well as PORTS Annual Environmental reports for the years 1959 to 1993 and found no excessive levels of chemicals or radionuclides. Also, fish samples taken by EPA and DOE did not show abnormal levels of any radionuclide or chemical that was discharged from the site.
The data and information contained in the Public Health Assessment for the Portsmouth Gaseous Diffusion Plant, CERCLIS number OH7890008983, was evaluated by the Health Activities Recommendation Panel (HARP) on March 1, 1995 for appropriate public health actions. HARP has determined that Site Specific Environmental Health Education is indicated.
Residents around the site allege numerous health effects from the site. DHS has reviewed the allegations and did not find levels of exposure with a plausible link to the site. The panel determined the need for site-specific environmental health education to help the community. The public health purpose for the determination is to address the community concerns that individual health outcomes are consistent with exposure to the substances present at the site, although there is no evidence of release at levels of health concern.
The Public Health Action Plan for the Portsmouth Gaseous Diffusion Plant contains a description of actions to be taken by ATSDR and other government agencies at and in the vicinity of the site after the completion of this public health assessment. The purpose of this public health action plan is to ensure that this public health assessment not only identifies public health hazards, but also provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment.
ATSDR has conducted the following public health action:
Based on the determinations of the ATSDR Health Activities Recommendation Panel, the community around the Portsmouth Gaseous Diffusion Plant received site-specific environmental health education. ATSDR provided a community health workshop on June 29, 1995 at the Vern Riffe Vocational School in Piketon, Ohio. This workshop was intended to help community members understand their health concerns, and how they can personally influence their own health.
DOE has installed a pump and treat system to prevent TCE contamination in groundwater, from migrating off-site.
Authors of Report
Michael D. Brooks, CHP
Health Physicist
Energy Section
Federal Facilities Assessment Branch
Jo A. Freedman, PhD, DABT
Toxicologist
Energy Section
Federal Facilities Assessment Branch
ATSDR acknowledges the contribution to this public
health assessment made by Lisa Spence and Jodi Lally
from the Boston University School of Public Health.
Reviewers of Report
Rita Ford
Energy Section Chief, Federal Facilities Assessment Branch
Sandy Isaacs
Acting Chief, Federal Facilities Assessment Branch
Richard Collins, MSEH, DAAS
Sanitarian, Energy Section, Federal Facilities Assessment Branch
ATSDR Regional Representative
ATSDR Regional Representative
Louise Fabinski
Senior Health Scientist, Regional Operations, Region V
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