ORRHES Meeting Minutes
April 22, 2003
The Chair called for public comments; no attendees responded.
Dr. Charp reported that the PHA explains ATSDR’s total dose and the methodology used to reach this conclusion. The approach was taken to identify no apparent health concerns, health hazards or doses of concern that would be sufficiently high to warrant a public health advisory. In this instance, ATSDR and CDC would issue a public health advisory for EPA to take appropriate actions. Of 30 public health advisories ATSDR has issued to EPA to date, five were related to radioactive contamination in the environment.
ATSDR may also be required to conduct further evaluations with site-specific parameters, specific conditions, scientific evidence and epidemiological investigations to determine if the dose is related to adverse health effects. This issue is explained in detail in an appendix of the PHA. The General Accounting Office (GAO) reviewed the literature and held discussions with federal agencies and outside experts to show that whole-body doses of >10,000 rem are well-known adverse health effects or in the range of well-verified effects. Whole-body doses of 5,000-10,000 rem are unknown, while those <1,000 rem are nearly impossible to verify.
ATSDR defines the MRL as the estimate of a daily human exposure to a substance that is likely to be without an appreciable risk of adverse non-cancerous health effects over a specific duration of exposure. Time periods for the MRL are categorized as an acute exposure of <14 days, an intermediate exposure of 14-365 days or a chronic exposure of >365 days. Studies used to derive the MRL were based on non-cancerous health effects rather than cancer impacts. For research designed to determine if radiation induced cancer, this effect would not have been reviewed because the purpose of the studies was to detect cancer problems. Locating radiation studies that focus on health effects other than cancer is extremely difficult.
During its evaluation, ATSDR found no data indicating that whole-body chronic exposures over 50-70 years cause cancer unless the dose was >5,000 mrem over this time period. ATSDR planned to conduct a more in-depth analysis of adverse health effects potentially associated with whole-body doses that were found to be above the comparison value of 5,000 mrem over 70 years. With the exception of the thyroid, this approach was important for uranium and other contaminant pathways. ATSDR’s comparison value was based on the following peer-reviewed literature:
- ATSDR toxicological profile of ionizing radiation.
- Conclusions from the GAO literature review.
- Study of nuclear shipyard workers.
- Research on the radium dial worker who did not develop bone cancer until doses reached >200 rad; 20,000 rem to the bone was used as the effective dose.
- Studies of nuclear medicine patients who received cardiac stress tests.
- Studies of nuclear workers in Canada, the DOE complex and the United Kingdom in which film badge data showed no whole-body adverse health effects until doses exceeded 3-4 rem.
In addition to these data sources, ATSDR applied EPA guidance from the Comprehensive Environmental Response, Compensation and Liability Act. The regulation requires radiologically contaminated sites to be cleaned to a risk-based level of 10-6-10-4. These figures equate to 1/10,000-1/1 million cancers; a dose of 15 mrem/year; a risk of ~5 x 10-4/rem; and a dose of 1,000 mrem over 70 years. ATSDR considered using a probability of causation to establish the comparison value, but two problems were identified. First, probability of causation is used to adjudicate worker compensation claims after a disease is diagnosed, but the comparison value is used to establish risk before disease develops.
Second, the relationship between radiation exposure and cancer risk must be known. Based on these issues, ATSDR used a whole-body dose of 5 mrem. During its meeting on the previous day, PHAWG asked ATSDR about the appropriateness of applying whole-body doses when certain organs receive much more of a radiation dose. The members pointed out that based on whole-body calculations, the radiation dose can be diluted over the entire body and would decrease. PHAWG also noted that the limit to any particular organ should not exceed 50 rem.
To address these concerns, ATSDR reviewed new weighting factors to particular organs, such as 20% to gonads, 12% to red bone marrow, 5% to the thyroid and 0.01% to bone surface. In applying the weighting factors to certain organs, the whole-body dose would be multiplied by 20 to estimate a dose to the thyroid and multiplied by 100 to estimate a dose to bone. ATSDR could not definitively determine whether a whole-body dose of 5,000 mrem would be sufficient or too high because bone may receive a dose of 500,000 mrem. ATSDR was also unable to inform PHAWG if the whole-body dose is protective of public health because some values are as much as 100 times higher to individual bone.
ATSDR’s screening value of 5,000 mrem was reduced to 500 to estimate uranium concentration in bone. The whole-body dose to a Scarboro resident was calculated in the PHA as <1 mrem. Applying the weighting factor and multiplying the dose by 100 would result in <100 mrem. The figure is below the ATSDR MRL of 100 mrem and the organ dose limit of 50,000 mrem. If a Scarboro resident exceeds the 5,000 mrem dose, ATSDR acknowledges that the entire PHA will need to be recalculated.
Ms. Adkins remarked that the PHA reflects exposure to a single contaminant, but persons most likely had cumulative exposures from uranium, nickel, mercury, lead and other metals. She asked if ATSDR plans to analyze synergistic effects from multiple exposures in one body. Dr. Charp confirmed that this methodology can be applied by adding doses for each individual isotope and then totaling all isotopes. Radiological doses from synergistic effects can be developed for the whole body and each organ. However, this strategy will be much more difficult for chemicals because an analysis to combine radiological and non-radiological doses has only recently been developed. Dr. Charp planned to forward Ms. Adkins’s request to ATSDR toxicologists.
Dr. Craig did not believe synergistic effects play a role in the PHA of Y-12 uranium releases. Scarboro was defined as the most exposed population, but the community is only at 1/100th of an action level. Moreover, the data showed that concentrations were within natural background. Mr. Hanley added that ATSDR responded to a previous action item to distribute literature references to ORRHES on the effects of mixture contaminants. The data showed that chemical mixtures do not always result in synergism and additive effects. If ATSDR evaluates more contaminants in the PHA, he raised the possibility of Dr. Karl Markiewicz presenting this issue at a future ORRHES meeting.
Mr. Lewis announced that Dr. Cember was absent from the PHAWG meeting the previous day. He asked that Dr. Cember be allowed to weigh in on outstanding issues from the technical deliberations. Dr. Charp requested Dr. Cember’s opinion on the screening dose that should be used to calculate a whole-body or organ dose and determine health effects. Dr. Cember would use an effective whole-body dose for prospective screening and an organ dose for retrospective screening. However, he clarified that unlike an organ dose, an effective whole-body dose is not an actual dose and cannot be measured. Dr. Cember provided additional details about the weighting factors referenced in Dr. Charp’s presentation.
The figures were developed to establish radiation safety standards for various substances and are not designed to retrospectively estimate the contribution of dose to illness. The dose amount taken into the body was used to calculate the probability of dying from cancer; the probability was then limited to a well-defined number of 1/10,000. The weighting factors represent a best estimate of the relative susceptibility of various organs to cancer based on excess cancer deaths among atomic bomb survivors. The sum of all weighting factors provides an overall probability of cancer death. If the acceptable intake for preventing or minimizing the probability of cancer death led to an organ dose that was sufficiently high to cause damage to the organs, the permissible intake would then be reduced.
If the acceptable intake for preventing cancer led to a large organ dose, the factor that limited intake on the material would be the threshold effect on the organ rather than cancer. From the perspective of establishing radiation safety standards, conservative estimates that yielded a lower intake were used. Dr. Charp inquired about the cut-off point between health issues and non-health effects for a particular organ.
Dr. Cember was not aware of any situations in which detrimental impacts occurred at non-cancerous doses of <50 rad. However, he acknowledged that health effects cannot be verified and may be masked by background noise during screening. His position was that 5 rad is a reasonable cut-off point for screening non-stochastic effects to organs. He explained that a stochastic effect can randomly develop whether or not exposure to an agent occurred. A non-stochastic effect will only develop with a minimum dose or if a threshold level of exposure to an agent occurred.
Ms. Dhelia Williamson of ATSDR provided an overview of this activity because the possibility of conducting an HSR in Oak Ridge is currently being considered. ATSDR uses HSRs to determine whether higher rates of a specific disease occurred at a particular site. To achieve this objective, ATSDR compares disease occurrence in the community of concern to county or state rates. For example, cancer rates in Oak Ridge would be compared to those in Tennessee or a particular county in the state. To obtain these data, ATSDR examines the number of persons who actually have the disease versus the number of cases expected in the area.
HSRs are conducted to respond to community concerns; provide specific information on the health status of a community; and examine outcomes associated with exposures to chemicals. State health departments may provide annual summaries on the rates of asthma, cancer, diabetes and other diseases to provide communities with the health status in a particular area. In developing HSRs, ATSDR only uses previously collected data, such as cancer, birth defects and other registry data as well as birth certificates, death records and other vital statistics. Data in registries are reported by physicians and hospitals to health agencies.
ATSDR acknowledges that each data source contains strengths and limitations. For example, only physical birth defects seen at delivery are reported by physicians. Malformations or internal health conditions are not captured on birth certificates. Death records only list the actual cause of death. For example, an individual with cancer who dies in an automobile accident would not be reported to the cancer registry. To conduct an HSR analysis, ATSDR examines the ratio between the observed number of cases in the area of concern and the expected number of cases based on county or state data. Particularly for cancer, the analysis accounts for age, race and gender.
HSR results provide data on the number of persons in an area who have or died from a specific disease. The findings also determine whether more cases are present in the area than would be expected in comparison to the county or state. HSRs have both strengths and limitations. One the one hand, HSRs respond to community concerns about disease occurrence in the area; specify particular geographic locations and disease outcomes to examine; and use established methods to conduct analyses. On the other hand, HSRs rely on available data; cannot determine the cause of disease; do not identify other risk factors that may be associated with the disease; provide no information on length of residence or occupational exposures; and generate unstable estimates due to a small number of cases.
Mr. Lewis outlined PHAWG’s rationale for ATSDR to conduct an HSR in Oak Ridge. Based on community concerns and other issues listed in the CHCD, many residents believe Oak Ridge has higher cancer rates and certain counties have an increased cancer incidence. To address these concerns, efforts will be made to examine the TDOH Cancer Registry and identify cancer incidence in particular counties or plume areas that may be associated with releases. PHAWG has discussed the possibility of TDOH presenting cancer statistics for the target counties.
Mr. Lewis asked Ms. Williamson to provide input on three issues of key interest to PHAWG: utilization of anecdotal data; ATSDR’s role in special testing on exhumed bodies; and the need for symptoms and disease prevalence studies. To fulfill its charge of developing recommendations to compile cancer registry data and analyze communities of interest, PHAWG reviewed or referenced several data sources to support the ORDR, including an HSR of concerns by Oak Ridge physicians and an HSR of mortality rates. No recommendation was made in the ORDR to perform an epidemiological study, but PHAWG has discussed the feasibility of revisiting this issue since more data on cancer incidence and other issues have now been generated.
PHAWG also reviewed the New York State web site and found age-adjusted county data on the incidence of thyroid cancer among females in the area from 1992-1996. The county figures are categorized as below, within or above a certain percentage of state rates. New York State released a brochure to compliment the study and inform the public about reading cancer maps and interpreting graphs. The study can be accessed at www.health.state.ny.us.
PHAWG hopes that after ATSDR collects HSR data from TDOH, a similar product can be developed for Oak Ridge. This information can assist ORRHES members and the lay public in better understanding the process to resolve problems in a specific geographic location. PHAWG recognizes that epidemiologists and other scientists are concerned about effectively applying and interpreting raw data.
Based on a previous presentation, PHAWG agrees that data should follow a continuum of decisions to actions. Data can be generated in the form of formal studies, television broadcasts, newspaper articles or other mechanisms. PHAWG’s interest in symptoms and disease prevalence studies was triggered by articles published in the Tennessean. The reports were based on hundreds of interviews of residents in Oak Ridge, Paducah, Kentucky and other sites.
To further support the HSR, Mr. Lewis cited several requests outlined in a letter from Tennessee Senator William Frisk to former HHS Secretary Donna Shalala: assess the quality or usefulness of data on which reports are based; examine data for any illness patterns and evaluate whether sufficient data exist to establish a relationship to nuclear plants; summarize HHS studies currently underway at 11 sites; identify a process to address key questions raised by the newspaper articles in a study; and describe existing federal programs that may assist in addressing medical needs of persons living near the plant.
In response to the first request, Mr. Lewis reported that data in the Tennessean articles were not compiled from an epidemiological study and have many limitations. For example, calculating rates for reported illnesses, determining whether illness rates were abnormal, and relating excess illness to specific nuclear plants are nearly impossible to calculate. The primary exposure was found to differ among plants. In response to the second request, Mr. Lewis noted that tabulating data collected in a non-standardized manner and assessing illnesses and symptoms based on limited diagnostic information are not acceptable from an epidemiological perspective. Determining whether data in the report represent a new or unusual occurrence of symptoms in the population is not possible.
Mr. Lewis confirmed that Senator Frisk’s letter will be incorporated into a case file of all data PHAWG has reviewed; the document will also be disseminated to ORRHES. The time-line of the project is proposed as follows. PHAWG has asked Ms. Williamson to examine county data and gather records from TDOH to analyze areas of concerns. Zip codes will also be evaluated to identify health effects. ATSDR will combine the county and zip code data to demonstrate whether releases of uranium or other contaminants may have contributed to increased cancer rates in the area.
After the conclusions are presented to ORRHES, PHAWG will submit the data to technical experts for a formal evaluation. Beyond the HSR, Mr. Lewis mentioned that PHAWG also discussed other potential uses of epidemiological data, such as individual behavioral changes, societal benefits or educational purposes. His position was that the lowest level to apply this information will be in zip codes where persons do not live in the respective regions.
Dr. Malmquist called ORRHES’s attention to a handout that was distributed in support of Mr. Lewis’s presentation. The document outlines PHAWG’s draft recommendations that are being proposed as a three-tier project. In Phase I, the TDOH Cancer Registry would conduct an HSR of cancer incidence in eight counties surrounding ORR. In Phase II, the TDOH Cancer Registry would use zip codes or census tracts and provide this information to ATSDR. PHAWG is requesting that the HSR be performed at this level because some cancer clusters may be overlooked at the county level.
In Phase III, ATSDR would obtain these data from TDOH and conduct the HSR in the event TDOH is unable to complete the activity. Dr. Malmquist announced that PHAWG unofficially asked TDOH to supply these data, but the information has not been received to date. As a result, PHAWG is asking ATSDR to officially request the data.
If ORRHES approves the HRS, Dr. Craig advised ATSDR to be mindful of other limitations of TDOH data. Most notably, data reporting is variable among counties and the quality of data submitted differs as well. Ms. Williamson responded to PHAWG’s requests outlined in Mr. Lewis’s presentation as follows. First, anecdotal data are included in ATSDR’s PHA. The information is captured as community concerns and statements by residents about the higher incidence of disease in a particular area. However, anecdotal data are typically not representative of the total community. As a result, the Tennessee HSR would be based on established data from disease registries and vital statistics.
Second, ATSDR’s mandate is limited to living persons in communities; the agency has no role in conducting special testing on exhumed bodies. Third, ATSDR has been reluctant to perform studies on symptoms and disease prevalence after the 1990s. These activities were extremely frustrating to ATSDR and communities because the results merely showed that certain symptoms or diseases were more prevalent in a particular area. Fourth, an analysis of cancer incidence data will address concerns about current cancer rates in the area, but the information cannot determine rates from historical exposures.
Ms. Williamson confirmed that ATSDR can use the PHA to closely collaborate with PHAWG and ORRHES in analyzing exposures, examining mortality rates and developing appropriate follow-up recommendations. Strategies to effectively implement these activities are currently being discussed by ATSDR. Ms. Sonnenburg inquired whether PHAWG has established a particular time period for data to be collected. She pointed out that the correct spelling of one of the counties in the recommendations is “Meigs.” Dr. Malmquist replied that the request for data will be consistent with the time period of TDOH’s existing computerized records.
Ms. Williamson added that the cancer registry maintains incidence data from 1990-1998. In ATSDR’s formal letter of request to Dr. Toni Bounds, the TDOH Cancer Registry Director, the time period and census tracts of interest will be clearly specified. Dr. Cember advised PHAWG to revise the recommendations with accurate language. For example, “cancer incidence” should be replaced with “cancer prevalence.” Ms. Williamson clarified that the use of “cancer incidence” in the document is correct because TDOH data are newly reported cases. Mr. Hill also made suggestions to refine the document: add “a possible” before “increased rate(s) of cancer” and include the zip code for each county listed.
Dr. Malmquist explained that zip codes were intentionally excluded from the recommendations because TDOH will not conduct a study in a population smaller than a county. Ms. Adkins mentioned that data sources for the HSR exclude topography and other factors to increase risk. As a result, TDOH or ATSDR will most likely conclude no health effects exist in Oak Ridge. Given the strong possibility of this outcome, she was uncertain about the rationale to undertake the study. Dr. Davidson reported that the HSR is being proposed in direct response to an ORRHES request. After Dr. Bounds’s presentation at a previous meeting, the members asked TDOH to provide data on cancer rates within the counties of concern.
Ms. Sonnenburg asked if data have been collected on the number of residents who moved into and from communities of concern over the past 50 years. For exposures that occurred in the 1950s or another time period, past residential status would play a critical role in addressing Ms. Adkins’s concerns and making the results more statistically significant. Ms. Williamson replied that information on historical residential status has not been collected. Another limitation in conducting the HSR will be mortality data due to the long latency period for cancer. For example, exposure may have occurred in the 1950s, but the disease could have been diagnosed several years later.
Mr. Johnson inquired about the feasibility of using both census data and TDOH records to cross-reference historical residential status. Ms. Williamson confirmed that ATSDR will use 1990 census data because the HSR will rely on TDOH Cancer Registry records. She remarked that the population within the target area will be considered during the analysis. In conducting the HSR, Ms. Brenda Vowell of TDOH advised ATSDR to also be aware of the fact that 1992 data are not as complete as 1997 information. If the HSR is approved, Ms. Adkins suggested that ORRHES play an active role in its design. For example, the members could select certain communities with the maximum air or water flow and pinpoint specific target populations that were most likely to receive the highest exposures.
Mr. Danny Sanders has been an Oak Ridge resident since his birth in the area in 1955. He was personally interested in the ongoing studies and the proposed HSR because both his parents died from cancer. He has attended ORRHES and PHAWG meetings over the past two months to learn more about historical exposures when ORR was initially established. His parents moved to the area in 1942 and lived in Happy Valley; the community was onsite at the K-25 plant.
Mr. Sanders was initially unable to locate data about the community, but PHAWG assisted him in this effort. However, he needs more assistance in locating additional data to address his concerns about cancer-causing agents. In conducting the HSR, Mr. Sanders urged ATSDR to historically research records to the extent possible. Due to TDOH’s data gaps, he acknowledged that a wealth of information will be missing. In a personal effort, he has been attempting to locate residents who lived in Happy Valley at the same time as his parents.
In addition to conducting the HSR and other formal studies, he encouraged ATSDR to also collect qualitative data by interviewing persons. This approach can assist in identifying health effects among current and future residents in communities of concern. He also asked ATSDR to refrain from limiting the HSR to 1990 census data. In response to Dr. Davidson, Mr. Sanders confirmed that he completed and submitted a concerns form to Ms. Dalton to be entered in the CHCD.
In response to Dr. Akin, Mr. Sanders commented that identifying a potential correlation between his parents’ cancers and the environment is important due to his concerns about historical health effects, future generations and a potential predisposition to the disease. Most notably, his two siblings who were born in Happy Valley in 1945 and 1947, respectively, may develop health impacts in the future. Dr. Davidson noted that Mr. Sanders’s concerns were consistent with ORRHES’s mission to address future health effects. Dr. Craig reported that ATSDR is scheduled to conduct a PHA of pollutants from the K-25 plant; the evaluation will include Happy Valley. He raised the possibility of placing this activity on a faster time-line to more quickly address Mr. Sanders’s concerns.
Mr. Ed Frome is a former ORRHES member. In support of the proposed HSR, he referenced an e-mail he transmitted to Mr. Hanley in August 2001 discussing the 1994 paper by Mangano on cancer mortality near Oak Ridge. The paper was also distributed to ORRHES members and ATSDR staff at that time. The study raises several statistical questions about the process to appropriately establish, design and implement an analysis. The communication was submitted into the record and is appended to the minutes as Attachment 1.
Mr. Frome offered to attend a future PHAWG meeting to answer questions or provide more information about the Mangano paper. Dr. Davidson confirmed that she would ensure Mr. Frome’s name is still included on the PHAWG e-mail distribution list. Dr. Akin emphasized the need for ORRHES to clearly delineate whether its focus is on historical exposures or protection of the current community. Dr. Davidson commented that the community is concerned with both issues. Dr. Malmquist’s position was that ORRHES should focus on whether Oak Ridge is currently a safe place to live.
Mr. Lewis provided additional details on PHAWG’s rationale for recommending that ATSDR conduct an HSR in Oak Ridge. Based on concerns raised by the community, issues documented in the CHCD and the lack of data in the ORDR, the need to gather additional information, conduct the HSR and address community concerns within the ORRHES charter is evident. The overall purpose of the activity will be to answer questions by the lay community on whether cancer rates in the area are higher than others based on a comparison of data from the TDOH Cancer Registry. Mr. Lewis added that the HSR will reflect a combination of environmental and occupational exposures.
Mr. Sanders pointed out that dose reconstructions are based on historical events and are performed to address public concerns about the cause of cancer among individuals. To achieve this goal in Oak Ridge, historical exposures will need to be traced to the initial establishment of ORR. If ORRHES attempts to determine whether past events during the years of maximum exposure in the community resulted in cancer or other diseases with a long latency period, Dr. Akin agreed efforts should be made to locate persons who lived in the area at that time. These individuals should serve as the study population. However, he was uncertain whether the study could be designed in this fashion.
COWG. Mr. Lewis reported that COWG has held several meetings to address specific issues. First, a matrix was developed to identify recipients of correspondence, appropriate persons to notify for particular activities and communication actions to take within COWG. However, the distribution list does not satisfy the need to create an ORRHES listserv, post the document on the web site and obtain commitment to maintain and update the database as needed. COWG has raised the possibility of holding a meeting with ATSDR management to discuss actions that should be taken to begin developing the ORRHES listserv.
Second, ATSDR’s nine-page briefing document of the PHA was reviewed and well-received by COWG. The summary is succinct and contains color pictures that will be easily understood by the lay public. Mr. Lewis commended ATSDR on this effort. COWG is now asking ORRHES to endorse the overall concept of the document if similar summaries will be disseminated to the community in the future. The briefing document should also be incorporated into the overall project plan with a clearly defined time-line for completion and distribution that is consistent with the release of the PHA.
Third, COWG has added key points and made other refinements to the community health concerns comment sheet. The document is expected to be highly effective. Fourth, a clear and transparent process must be developed to capture all action items. Mr. Lewis acknowledged that some recommendations raised during COWG and ORRHES meetings are not transferred to the formal list. For example, Dr. Cember was concerned that presenting data in the PHA in units of rem, mrem and rad will be too technical for the lay public.
To respond to this issue, ATSDR developed a thermometer graph to illustrate the units of measure. COWG also learned that Dr. Malinauskas wrote a paper on this issue for the Three Mile Island incident. A recommendation was made to obtain the study for inclusion into the formal ORRHES record. Mr. Lewis underscored the need for solid scheduling, accurate record keeping and management support to effectively and efficiently implement action items.
HENAWG. Ms. Theresa NeSmith of ATSDR reported that completion and release of the draft needs assessment to ATSDR is scheduled for May 30, 2003. The document will be disseminated to HENAWG for review and comment; HENAWG will then formulate recommendations for consideration by ORRHES. In response to Ms. Sonnenburg’s concerns, Ms. NeSmith confirmed that the draft will be sent to HENAWG via FedEx prior to May 30, 2003 if ATSDR receives the draft before this time.
Dr. Davidson agreed with Ms. Sonnenburg’s comments. HENAWG will be extremely burdened by receiving the draft needs assessment after May 30, 2003, thoroughly reviewing the document and then developing formal recommendations for ORRHES to consider at the June 3, 2003 meeting. She suggested that HENAWG’s recommendations be tabled until the following ORRHES meeting on July 29, 2003.
Based on Dr. Davidson’s observations, Ms. NeSmith summarized the revised time-line. ATSDR will send the draft needs assessment to HENAWG via FedEx no later than May 30, 2003. HENAWG will be provided a comment period from time of receipt of the document until July 29, 2003. The draft will be circulated to the full ORRHES prior to the July 2003 meeting to prepare for HENAWG’s recommendations.
PHAWG. Dr. Craig reported that PHAWG’s ongoing activities were extensively discussed in previous presentations, i.e., input on the public comment draft of the ATSDR PHA on Y-12 uranium releases; review of screening levels; and initial planning of the HSR. However, the mercury PHA is another current PHAWG project that was not mentioned. The members held a meeting to preliminarily discuss this issue; development of the mercury PHA by ATSDR is currently underway.