PUBLIC HEALTH ASSESSMENT
POLES, INCORPORATION WOOD TREATMENT FACILITY
OLDTOWN, BONNER COUNTY, IDAHO
APPENDIX A: OLDTOWN LOCATION AND POLES, INCORPORATED SAMPLING MAP
Figure A-1. Oldtown Location Map
Figure A-2. Poles Inc. Sampling Location Map
APPENDIX B: HEALTH CONSULTATION #1
HEALTH CONSULTATION
Evaluation of Potential Pentachlorophenol Air Contamination
Based on the Idaho Department of Environmental Quality
April 2001 Air Modeling Results
POLES, INCORPORATED WOOD TREATING FACILITY
OLDTOWN, BONNER COUNTY, IDAHO
EPA FACILITY
ID: ID0002406635 
September 19, 2001
Prepared by:
Idaho Department of Health Welfare
Bureau of Environmental Health and Safety
Division of Health
Under a Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry
2. PURPOSE AND SITE DESCRIPTION
4. CHILD HEALTH INITIATIVE STATEMENT
9. PREPARERS OF REPORT AND CERTIFICATION
APPENDIX A: ATSDR PUBLIC HEALTH HAZARD CATEGORY
| ATSDR | Agency for Toxic Substances and Disease Registry |
| BEHS | Bureau of Environmental Health and Safety |
| CAG | Community Advisory Group |
| CDRI | Cancer Data Registry of Idaho |
| EPA | Environmental Protection Agency |
| IARC | International Agency for Research on Cancer |
| IDEQ | Idaho Department of Environmental Quality |
| ISDA | Idaho State Department of Agriculture |
| PAHs | Polycyclic aromatic hydrocarbons |
| PCP | Pentachlorophenol |
| RBC | Risk Based Concentration |
| TWA | Time-weighted Average |
| USDA | U.S. Department of Agriculture |
What is pentachlorophenol (pronounced pen'ta-klor'o-fee'nol)?
Pentachlorophenol (PCP) is a manufactured chemical not naturally found in the environment and is a registered biocide (or pesticide). Only one company in the United States currently makes it, but in the 1970s it was one of the most widely used biocides in the United States. Since the 1980s, PCP has no longer been available to the general public for use. Only applicators certified by the U.S. Department of Agriculture (USDA) are allowed to purchase and use it. Therefore, it is no longer found in wood preserving solutions or insecticides and herbicides that you can buy for home and garden use. It is now used in industry as a wood preservative for power line poles, railroad ties, cross arms, and fence posts.
Pure PCP occurs as a colorless crystal. It has a sharp chemical odor when hot but very little smell at room temperature. The impure form is a dark gray to brown dust, beads, or flakes. People are generally exposed to technical-grade PCP, which usually contains toxic impurities such as polychlorinated dibenzo-p-dioxins and dibenzofurans. Pure PCP is typically only found in laboratory settings.
Why are residents in Oldtown concerned about pentachlorophenol exposure?
Poles Inc., in Oldtown, Idaho is a wood treatment facility that uses PCP as a wood preservative in a heated dip tank process. In the small community, an elementary school and several residences are located close to the facility. Parents of school children, the school administration, and area residents are concerned about the facility's use of PCP and its potential health effects.
Has pentachlorophenol in air in Oldtown reached hazardous levels?
We are uncertain because there are no site-specific air monitoring data available. In April 2001, the Idaho Department of Environmental Quality (IDEQ) used a computer modeling technique to estimate the potential PCP concentrations in the outdoor air adjacent to the facility. Due to the lack of site-specific data, the IDEQ air modelers used 1983 sampling data from a similar wood treating facility in Sandpoint, Idaho, made basic meteorology assumptions, and calculated the possible PCP concentrations around the nearby school and residences (see details in Section 3 Discussion).
The Bureau of Environmental Health and Safety (BEHS), Division of Health, Idaho Department of Health and Welfare thoroughly reviewed IDEQ's April 2001 air modeling report. Based on IDEQ's air modeling estimation at that time, PCP concentrations around the nearby school and residences are considered as an indeterminate public health hazard see Appendix A). This classification is used because concentrations of PCP were estimated using computer modeling that poses high uncertainty and the Sandpoint site data may not be comparable to the Oldtown site. BEHS recommends that air monitoring be performed at the Oldtown, Idaho site to adequately address health concerns.
Does pentachlorophenol cause cancer?
There is weak evidence that PCP causes cancer in humans. No studies were found regarding cancer in animals after inhalation exposure to PCP. An increased risk of cancer has been shown in some laboratory animals given large amounts of PCP orally for a long time. The International Agency for Research on Cancer (IARC) has determined that PCP is possibly carcinogenic to humans, and the Environmental Protection Agency (EPA) has classified PCP as a probable human carcinogen. Since humans are generally exposed to technical-grade PCP, which contains impurities, some of the cancerous effects observed in humans may be related to the presence of the impurities. For the permitting of industrial sources (IDAPA 58.01.01.585), the IDEQ lists PCP as a non-carcinogenic toxic air pollutant with established levels. However, IDEQ may consider changing the classification to a carcinogenic toxin.
Is there a medical test to determine whether I have been exposed to pentachlorophenol?
PCP can be measured in the blood, urine, and tissues of exposed persons. Because urine and blood samples are easily collected, testing these fluids is a good way to determine whether or not a person has been exposed. However, these bio-monitoring tests cannot be used to show how severe resulting health effects may be. Additionally, because PCP leaves the body fairly quickly, these tests are best for finding exposures that occurred within the last several days. The tests are usually not available at a doctor's office because they require the use of special equipment. Special arrangements for testing should be made with your health care provider, if possible.
Based on samples taken in studies prior to 1989, background levels of up to 0.1 ppm PCP could be found in blood and urine in the general population who had no recognized exposure to PCP.
Are there other potential routes of exposure to pentachlorophenol from Poles, Inc., besides breathing it?
We are uncertain because a thorough site investigation has not yet been done. PCP can be released into the atmosphere as vapor during wood treating process or from evaporation of treated wood products. PCP can enter surface water or soil from improper waste disposal, accidental spills, or from the atmosphere through wet deposition (rain or snow). Humans can absorb PCP through all routes of exposure. Small children who have the tendency to eat soil and to put their hands and foreign objects in their mouth might be at a higher risk of exposure to contaminated soil. The BEHS recommends that soil, surface water, and ground water sampling be conducted, as well as air sampling in Oldtown, Idaho.
Have I been exposed to other chemicals from Poles, Inc.?
It is possible. Technical grade PCP contains 83% - 93% pure PCP, 0.6% - 3 % 2,3,4,6-tetrachlorophenol, 3.5% - 12 % other chlorophenols and related compounds, and 0% - 4% of chlorinated impurities (such as polychlorinated dibenzo-p-dioxins and dibenzofurans) (Vulcan 1999). To further complicate the matter, the pole treating oil that is mixed with technical-grade PCP contains polycyclic aromatic hydrocarbons (PAHs) which can be released during the process of heating an oil/PCP mixture. There are more than 100 different PAHs that generally occur as complex mixtures. Since we do not have enough information regarding site-specific facility processes, it is not possible to determine which chemical(s) may have reached the nearby school and community and at what levels. BEHS recommends expanding the focus of the site investigation to other potential chemicals in addition to PCP.
Where can I get more information?
If you have more questions or concerns, please contact Paula Lyon with IDEQ at 208-769-1422 or plyon@deq.state.id.us; or contact Dr. Mingyi Wen with BEHS at 208-334-0606 or wenm@idhw.state.id.us.
2. PURPOSE AND SITE DESCRIPTION
Poles Inc., located in Oldtown just west of Priest River in the Panhandle of Northern Idaho, Bonner County, is an open vat thermal wood treating facility using pentachlorophenol (PCP) as a wood preservative. It has been in operation since 1945. The wood dipping tank at Poles Inc. is 95'x8'xl2'deep. In a typical treating cycle, 150 raw logs are placed in the tank and PCP oil solution is pumped into the tank at 60°F. The PCP oil solution (5% PCP mixed with Imperial Pole Treating Oil) is circulated through a steam heat exchanger. An oil-fired boiler is located adjacent to the dipping tank and provides steam for the heat exchanger. It takes approximately 3.5 hours to heat the oil mixture to 225°F for the wood treating process. The heated oil is then held in the tank for an additional 3.5 hours before it is drained off. Cool oil is pumped back into the tank for another hour to cool the wood. Poles Inc. replaced an old wood-fired boiler with the new oil-fire boiler in Fall 1999. The heating time, as well as the whole wood treating process, was significantly reduced from approximately 13 to 8 hours. Since Poles Inc. only utilizes one dip tank, the facility can only treat a maximum of two to 2.5 batches per week. Typical production is one batch of poles per week (IDEQ 2000). Poles are treated in two ways: the whole pole is submerged in the PCP, or just one end of the pole is dipped in the PCP, called butt dipping. During the whole pole treating process the lids to the dipping tank are closed. During the butt-dipping process, the lids on the tank remain open. According to the former plant manager, the dip tank is covered at all times except when adding or removing poles to keep precipitation out of the tanks. By keeping precipitation out, the dip tank does not form or accumulate waste sludge. As a result, the former manager claimed that Poles Inc. has never had to clean its dip tank (EPA 1993). This statement conflicts with a statement made by a former worker in a January 2001 community meeting, in which the former worker openly stated that he used to personally enter the dip tanks to shovel out the waste sludge. IDEQ discussed this discrepancy with the current plant owner who stated that the removal of waste sludge occurred during 1970s before the cover was installed. During 1970s while PCP was not a restricted pesticide, the waste sludge was legally distributed to local communities for private use. However, this practice of giving away sludge has been eliminated since the early 1980s. BEHS will further investigate and address this issue in a future Health Consultation.
The facility operates nine months of the year and is closed during December, January, and February. The nearest residence is approximately 400 feet north of the facility. The Idaho Hill Elementary School is located approximately 500 feet south of the facility and situated on a hill approximately 30 feet higher in elevation than the site. The Pend Orielle River flows in the east to west direction and it is approximately 400 feet north of the facility dip tank (IDEQ 2000).
In fall 2000, several teachers, school administrative staff, and community members raised concerns about a strong chemical smell coming from the facility during its pole dipping treatment. People experienced eye and throat irritation, headaches, and nausea during the process. The teachers and school administrative staff formed a Healthy Building Committee and contacted the IDEQ, BEHS, and the Cancer Data Registry of Idaho (CDRI) to further investigate the potential exposures and health effects of PCP. The community members were also concerned with what was perceived as a cancer cluster in Oldtown. Anecdotally, there were/are 10 or possibly 11 historical/current cancer cases in nearby residents and workers. In response to community requests, the CDRI performed a cancer incidence/prevalence study for the zip code of Oldtown and found no elevated cancer rates for the zip code. Since Oldtown is a relatively small area, people commute to Oldtown for work or school from different areas or zip codes. BEHS and CDRI could not rule out the possibility of underestimating the risk (Johnson 2001).
During a site visit conducted by IDEQ on October 19, 2000 with Poles Inc., no objectionable odors were detected and fugitive dust emissions were well controlled. However, the plant was not actively treating poles during the visit (IDEQ 2000). After the site visit, Poles Inc. changed their pole dipping treatment schedule so the dip tank process occurred when Idaho Hill Elementary was not in session. This schedule continued when they restarted operations in the Spring of 2001.
In January 2001, a public meeting was convened by IDEQ to discuss what actions the agency would take in response to the public concern. BEHS also participated in the meeting and discussed the development of a health consultation. Following the meeting, IDEQ performed an initial evaluation of potential inhalation exposure to PCP utilizing two air dispersion models called the back model and the SCREEN3 model (IDEQ 2001) in April. BEHS, as part of its cooperative agreement with ATSDR, reviewed IDEQ's April 2001 air modeling report and has prepared this Health consultation to partially address public health concerns. This Health consultation only addresses the potential health effects from exposure to PCP through inhalation based on the IDEQ April 2001 air modeling results, it does not address soil and groundwater contamination, the variety of exposure routes, or other chemicals.
In May 2001, BEHS formed the Oldtown Community Advisory Group (CAG). The CAG is composed of representatives from Oldtown and nearby communities, the Healthy Building Committee, and People for Environmental Action and Children's Health. Agency representatives from BEHS, IDEQ, Idaho State Department of Agriculture (ISDA), EPA, and the Agency for Toxic Substances and Disease Registry (ATSDR) also participate in the advisory group process. During this May 2001 meeting IDEQ discussed the results of the April 2001 air dispersion modeling. Additionally, the CAG suggested that BEHS conduct a health study. After evaluating all of the exposures at the site, BEHS along with ATSDR will determine the need for a health study.
Lastly, an additional meeting of the CAG was convened in June 2001 by EPA to discuss the multiple, ongoing activities that are currently being conducted by EPA and IDEQ. A detailed discussion of these activities is not necessary for the purposes of this health consultation, however the activities are discussed briefly in the public health action plan section of this health consultation.
The following information is provided to the community to assist them in understanding the potential health effects of PCP and PAHs. Currently, extensive environmental sampling data is not available for the site. Therefore, it is not possible to know if people in the community are being exposed to PCP and PAHs at levels which may result in the health effects described below.
PCP is a man-made substance, and does not occur naturally in the environment. During the 1970s it was one of the most widely used biocides (a pesticide substance that is destructive to many different organisms) in the United States. As of the 1980s, purchase and use of PCP is restricted to applicators certified by the USDA (ATSDR 2000).
There is limited information available regarding PCP toxicity in humans for the inhalation route. Some, but not all, of the harmful effects associated with exposure to PCP are due to impurities present in commercial PCP. Short exposure to large amounts of PCP in the work place or through the misuse of products can cause harmful effects to the liver, blood, lungs, nervous system, immune system, and gastrointestinal tract. Contact with PCP (particularly in the form of hot vapor) can irritate the skin, eyes, and mouth. If large amounts enter the body, heat is generated, causing an increase in body temperature. Exposure to small amounts of PCP for a long time may cause damage to the liver, kidneys, blood, and nervous system.
Because we do not have reliable human exposure information, levels of exposure that affect human health must be estimated from animal studies. PCP has been shown to cause immune system defects, liver and kidney damage, and blood disorders, as well as reproductive failures (miscarriage or abnormal menstrual cycle) in experimental animals. The liver appears to be the target organ for PCP- induced toxicity in experimental animals following a single exposure to PCP by mouth at doses greater than 10 milligrams per kilogram body weight (mg/kg). However, we do not know if PCP produces all of the same health effects in humans that it causes in animals.
No studies were found regarding cancer in animals after inhalation exposure to PCP. Case reports suggest a possible association between cancer (Hodgkin's disease, soft tissue sarcoma, and acute leukemia) and occupational exposure to technical-grade PCP. However, in all of these cases, concurrent exposure to other toxic substances may have contributed to the effects seen. An increased risk of liver, kidney, and blood vessel tumors has been shown in some laboratory animals that were given technical-grade PCP orally. The IARC has determined that PCP is possibly carcinogenic to humans, and the EPA has classified PCP as a probable human carcinogen (IRIS 1987).
PAHs are a group of chemicals that can be formed during the incomplete combustion or burning of coal, oil, gas, wood, garbage, or other organic substances. Some PAHs are part of the pole-treating oil and they became more volatile when heated, therefore, they enter the environment more easily. There are more than 100 different PAHs. Several PAHs (benz[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[j]fluoranthene, chrysene, dibenz[a,h]anthracene, and indeno[1,2,3-d,d]pyrene) are considered probable human carcinogens by EPA. Typically a person is not exposed to an individual PAH, but to a mixture of them (ATSDR 1995).
Studies in animals have shown that PAHs can cause harmful effects on skin, body fluids, and the immune system. PAHs have been shown to cause cancer in laboratory animals when the animals breathed PAHs-contaminated air (lung cancer), ate PAHs-contaminated food (stomach cancer), or had skin contact with PAHs (skin cancer).
Data from an occupational PCP exposure study conducted for McFarland Cascade in Sandpoint, Idaho in 1983 were used as the basis of IDEQ's April 2001 air modeling for Oldtown. McFarland Cascade is a similar PCP thermal wood treating facility with a covered dipping tank. During one sampling event, there were four samples collected at the edge of the wood treating pit. The measured PCP concentrations were 2.71, 2.89, 2.05, and 1.47 milligrams per cubic meter (mg/M3) (McFarland Cascade 1983). IDEQ used a box model as back-modeling technique to estimate a PCP emission rate from the Poles Inc. dipping tank. Three emission rates, the upper bound estimate, the best estimate, and the lower bound estimate were calculated. Utilizing the estimated emission rates, the SCREEN3 model was then used to predict one-hour PCP concentrations at the nearby school (500 feet) and residence (400 feet). The results are presented in Table 1.
Table 1. IDEQ air modeling results for PCP
| Location | Predicted PCP Concentration in mg/M3 (concentration range) |
| 1 hour maximum at school | 0.04 (0.005-0.3) |
| 1 hour maximum at nearby residence | 0.03 (0.003-0.18) |
| 1 hour maximum at nearby residence at night | 0.6 (0.06-4.0) |
Adapted from IDEQ 2001.
Two other techniques were also used to calculate estimated PCP emission rates for the Poles, Inc. dipping tank. These techniques produced emission rates comparable to the lower bound estimates from the box model method. However, BEHS, IDEQ, and ATSDR later agreed that these two techniques were not appropriate for the situation in Oldtown. Therefore, results from these two techniques are not discussed in this Health consultation.
BEHS compared the predicted PCP concentrations to available environmental and occupational standards. Ambient air concentrations tend to be higher at night because the night atmosphere is more stable. Less turbulence and lower temperature (likely night condition) means higher possible concentrations. The highest IDEQ estimation at the nearest residence during the night could be 4 mg/M3, higher than the Immediately Dangerous to Life and Health concentration of 2.5 mg/M3 set by the National Institute for Occupational Safety and Health. However, this estimated level is also higher than all of the original data points collected adjacent to the treating pit at the McFarland Cascade facility making the highest estimate an unlikely situation. This tells us the model predictions may be overly protective.
The IDEQ best estimate PCP concentration in the night, 0.6 mg/M3 is higher than 0.5 mg/M3 which is the time-weighted average (TWA) set by the American Conference of Governmental Industrial Hygienists. TWA value was set for a normal 8-hour workday and a 40-hour workweek, to which nearly all workers may be repeatedly exposed day after day, without expecting adverse health effects. The one-hour estimate during the night ranged from 0.06 to 4 mg/M3. There is a possibility that the nearby residence may be exposed to PCP at concentrations higher than 0.5 mg/M3 for as long as (or longer than) 8 hours. Besides, the general population, which includes the elderly, pregnant women and children, is more sensitive to chemical exposures than healthy workers.
Since the SCREEN3 model calculates for a one-hour maximum PCP concentration, the estimated concentration needs to be adjusted to a 24-hour average (multiplied by a persistence factor of 0.4) in order to compare it with Idaho's ambient air standard for PCP which is 0.025 mg/M3 (EPA 1988). A persistence factor varies depending on chemical property and the contamination source. For this specific situation, 1-hour to 24-hour conversion was chosen to be 0.4 (recommended range from 0.2- 0.6). After adjusting this factor, the 24-hour estimated ambient air PCP concentration in the worst case scenario (to be conservative, using the nearby residence night data to extrapolate) would be 0.24 mg/M3 with a range from 0.012 to 1.6 mg/M3. Based on these results, there remains a chance that the PCP concentration could exceed the Idaho ambient air standard.
Idaho's ambient air PCP standard was set without considering PCP's potential carcinogenic effects. Since the community members have repeatedly expressed concerns about the potential cancerous effects of PCP, BEHS compared estimated PCP concentrations to the EPA Region III Risk Based Concentration (RBC) for PCP, which assumes it is a carcinogen. The EPA Region III RBC for PCP is 0.000052 mg/M3. All IDEQ April 2001 air modeling estimated concentration points significantly exceed this standard.
4. CHILD HEALTH INITIATIVE STATEMENT
Children sometimes differ from adults in their susceptibility to hazardous chemicals, but whether there is a difference depends on the chemical. We do not know whether children under 18 years of age differ from adults in their sensitivity to the health effects of PCP. There is some evidence that birth defects were found in the children of fathers who had been exposed to dioxin contaminated PCP (ATSDR 2000).
Since the Idaho Hill Elementary playground is close to the Poles Inc. site, small children who have the tendency to eat soil and to put their hands and foreign objects in their mouth might be at a higher risk of soil exposure if found to be contaminated.
Based on IDEQ's air modeling results, the BEHS determined that the estimated PCP concentration around the nearby school and residences may be a concern. Since there are multiple uncertainties regarding the use of computer models rather than sound environmental sampling, BEHS considers the potential exposure to the estimated air PCP concentration from air modeling to be an indeterminate public health hazard. Indeterminate public health hazard is one of the five public health categories identified by ATSDR (Appendix A). PCP can be released into the atmosphere during wood treating processes or from evaporation of treated wood products. PCP can enter surface water or soil from improper waste disposal, accidental spills, or from the atmosphere through wet deposition (rain or snow). People can absorb PCP through all routes of exposure. In summary, the uncertainties related to the air modeling include the following seven factors:
Given the community concerns, high uncertainties in IDEQ's April 2001 air modeling outcomes, and potentially high PCP concentrations at the nearby school and residence, BEHS recommends that a thorough site exposure investigation be conducted at the Oldtown site. The site investigation should consider all potential exposure pathways (soil, water, and air). The details about sampling methods and timing of the sampling event will be discussed and agreed among EPA, ATSDR, IDEQ, BEHS, and the facility (Poles Inc.). BEHS will be continuously involved in the process to gather site specific information and to make the best scientific judgement.
BEHS, IDEQ, ATSDR, and EPA have conducted or are currently planning the following public health actions:
ATSDR 1995. Toxicological Profile for Polycyclic Aromatic Hydrocarbons (PAHs) (update). U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. Atlanta, GA.
ATSDR 2000. Toxicological Profile for Pentachlorophenol (update). U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. Atlanta, GA.
EPA 1988. Screening Procedures for Estimating the Air Quality Impact of Stationary Sources, PB89- 159396, U.S. Environmental Protection Agency. Research Triangle Park, NC.
EPA 1993. RCRA Compliance Inspection Report, EPA ID009061714. U.S. Environmental Protection Agency, Seattle, WA.
IDEQ 2000. Oldtown Air Quality Inspection Report, Airs No. 017-00039. Idaho Department of Environmental Quality. Coeur d'Alene, ID.
IDEQ 2001. Summary of Analysis: Ambient Air Impact of Pentachlorophenol from Poles, Inc. Idaho Department of Environmental Quality. Boise, ID.
IRIS 1987. Integrated Risk Information System Substance File - Pentachlorophenol
(CASRN 87-86-5), http://www.epa.gov/iriswebp/iris/index.html
. U.S. Environmental Protection
Agency.
Johnson, C.J. 2001. Personal Communication. Cancer Data Registry of Idaho. Boise, ID.
McFarland Cascade 1983. Pentachlorophenol Atmospheric Sampling Program for McFarland Cascade Sandpoint Facility. Safety and Health Consultation Program, Department of Community and Environmental Health, School of Health Sciences, Boise State University. Boise, ID.
Vulcan 1999. Material Safety Data Sheet from Vulcan Chemicals, A Business Group of Vulcan Materials Co. GLAZD®.
9. PREPARERS OF REPORT AND CERTIFICATION
Preparers of Report:
Mingyi Wen, Sc.D.
Public Health Assessor/Toxicologist
Elke Shaw-Tulloch
Manager, Environmental Health Education Program
Bureau of Environmental Health and Safety
Division of Health
Idaho Department of Health and Welfare
ATSDR Technical Project Officer:
Gregory V. Ulirsch
Environmental Health Engineer
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Any questions concerning this document should be directed to:
Mingyi Wen, Sc.D.
450 W. State St., 4th floor
P.O. Box 83720
Boise, ID 83720-0036
208-334-6584
wenm@idhw.state.id.us
Certification:
The Idaho Bureau of Environmental Health and Safety prepared this Health consultation under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation was initiated.
Gregory V. Ulirsch
Technical Project Officer, SPS, SSAB, DHAC
The Superfund Site Assessment Branch (SSAB), Division of Health Assessment and Consultation (DHAC), ATSDR has reviewed this health consultation and concurs with its findings.
Lisa C. Hayes
for Chief, SSAB, DRAC, ATSDR
APPENDIX A: ATSDR INTERIM PUBLIC HEALTH HAZARD CATEGORY
Interim Public Health Hazard Categories
| Urgent Public Health Hazard This category is used for sites where short-term exposures (<1yr to hazardous substances or conditions could result in adverse health effects that require rapid intervention. |
This determination represents a professional judgment based on critical data, which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made. | Evaluation of available relevant information* indicated that site-specfic conditions or likely exposures have had, are having, or are likely to have in the future, an adverse impact on human health that requires immediate action or intervention. Such site-specific conditions or exposures may include the presence of serious physical or safety hazards. |
| Public Health Hazard This category is used for sites that pose a public health hazard due to the existence of long-term exposures (>1yr) to hazardous substance or conditions that could result in adverse health effects. |
This determination represents a professional judgment based on critical data, which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made. | Evaluation of available relevant information* suggests that, under site-specific conditions of exposure, long-term exposures to site-specific contaminants (including radio nuclides) have had, are having, or are likely to have in the future, an adverse impact on human health that requires one of more public health interventions. Such site-specific exposures may include the presence of serious physical or safety hazards. |
| Indeterminate Public Health Hazard This category is used for sites in which "critical" data are insufficient with regard to extent of exposure and/or toxicological properties at estimated exposure levels. |
This determination represents a professional judgment that critical data are missing and ATSDR has judged the data are insufficient to support a decision. This does not necessarily imply all data are incomplete; but that some additional data are required to support a decision. | The health assessor must determine, using professional judgment, the "criticality" of such data and the likelihood that the data can be obtained and will be obtained in a timely manner. Where some data are available, even limited data, the health assessor is encouraged to the extent possible to select other hazard categories and to support their decision with clear narrative that explains the limits of the data and the rationale for the decision. |
| No Apparent Public Health Hazard This category is used for sites where human exposure to contaminated media may be occurring, may have occurred in the past, and/or may occur in the future, but the exposure is not expected to cause any adverse health effects. |
This determination represents a professional judgment based on critical data, which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made. | Evaluation of available relevant information* indicates that, under site-specific conditions of exposure, exposures, exposures to site-specific contaminants in the past, present, or future are not likely to result in any adverse impact on human health. |
| No Public Health Hazard This category is used for sites that, because of the absence of exposure, do NOT pose a public health hazard. |
Sufficient evidence indicates that no human exposures to contaminated media have occurred, none are now occurring, and none are likely to occur in the future. |
* Such as environmental and demographic data; health outcome data; exposure data; community health concerns information; toxicologic, medical, and epidemiologic data; monitoring and management plans.
APPENDIX C: HEALTH CONSULTATION #3
HEALTH CONSULTATION
Technical Assistance to the Oldtown Community Advisory Group
POLES, INCORPORATED WOOD TREATING FACILITY
OLDTOWN, BONNER COUNTY, IDAHO
EPA FACILITY ID: ID0002406635
April 3, 2002
Prepared by:
Idaho Department of Health and Welfare
Bureau of Environmental Health and Safety
Division of Health
Under a Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry
SITE DESCRIPTION AND BACKGROUND
PREPARERS OF REPORT AND CERTIFICATION
| ATSDR | Agency for Toxic Substances and Disease Registry |
| BEHS | Bureau of Environmental Health and Safety |
| CAG | Community Advisory Group |
| CDRI | Cancer Data Registry of Idaho |
| EPA | Environmental Protection Agency |
| IA | Integrated Assessment |
| IARC | International Agency for Research on Cancer |
| IDEQ | Idaho Department of Environmental Quality |
| mg/kg/day | milligrams per kilogram per day |
| MRL | Minimal Risk Level |
| RED | Reregistration Eligibility Decision |
| SQAP | Sampling and Quality Assurance Plan |
| START | Superfund Technical Assessment Response Team |
The Bureau of Environmental Health and Safety (BEHS), Idaho Division of Health, Department of Health and Welfare, prepared this Health Consultation under its cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR) to document the BEHS response to several Oldtown Community Advisory Group e-mails requesting more in-depth explanations about our activities and decisions. The health consultation addresses those specific issues raised in the e-mails. In the discussion section you will see a bold heading with accompanying explanatory text. The bolded, italicized heading delineates the issue/question posed to BEHS. The text that follows is our explanation to the issue/question raised.
SITE DESCRIPTION AND BACKGROUND
Poles Inc. is located in Oldtown just south of Pend Oreille River in the Panhandle of Northern Idaho. The facility has produced pentachlorophenol-treated utility poles since 1945. The facility currently operates nine months out of the year. An elementary school (Idaho Hill Elementary) and multiple residences are within proximity of the site.
In fall 2000, teachers from Idaho Hill Elementary and community members formed the Healthy Building Committee. The committee requested the Idaho Department of Environmental Quality (IDEQ) to investigate an irritating chemical smell coming from the facility during its pole treating process. Following the request, IDEQ performed an evaluation of potential inhalation exposure to PCP using two air dispersion models called the Back Model and the SCREEN3 Model (IDEQ 2001). BEHS reviewed IDEQ's report and determined that modeled PCP concentrations may pose a public health concern if they are representative of actual exposure levels. Therefore, because of multiple uncertainties regarding the use of computer models, BEHS recommended that a thorough environmental investigation be conducted at the Oldtown site. Details are summarized in the previous Health Consultation titled "Evaluation of Potential Pentachlorophenol Air Contamination Based on the Idaho Department of Environmental Quality April 2001 Air Modeling Results" (BEHS 2001a). BEHS formed the Community Advisory Group (CAG) during the process of drafting the previous Health Consultation to ensure community involvement. In summary, BEHS suggested that the environmental investigation should include multiple environmental media and that it should be expanded to focus on potential contaminants other than PCP. In August 2001, the Environmental Protection Agency (EPA) Superfund Technical Assessment and Response Team (START) completed an Integrated Assessment (IA) Sampling and Quality Assurance Plan (SQAP) for Poles Inc., and subsequent environmental sampling. BEHS reviewed the SQAP and provided review comments in the health consultation titled, "Evaluation of EPA's Integrated Assessment Sampling and Quality Assurance Plan for Poles, Inc." Prior to the start up of the sampling activities, START reviewed the suggestions and agreed to incorporate them in its IA SQAP.
This health consultation addresses questions raised by the Oldtown CAG before the EPA IA final report was released in January 2002. By the time this health consultation is published, BEHS will have reviewed the IA sampling results and begun preparation of a public health assessment for the site.
Focus of the Bureau of Environmental Health and Safety (BEHS) and the Agency for Toxic Substances and Disease Registry (ATSDR) as Public Health Agencies:
BEHS and ATSDR assess chemical exposures or the potential for exposures and assess whether or not people may experience harmful health effects from those exposures. Unlike the EPA health risk assessment process that addresses current or future exposures from a regulatory perspective, the public health assessment process looks at past, present and future exposures from a human health effects perspective. BEHS and ATSDR determine the chemical(s) of concern based on environmental data collection conducted by others, assess the hazards associated with those chemicals and determine if there was, is or will be exposure. The level of hazard to people based on the magnitude and duration of the exposure is then assessed. In the case of Oldtown, BEHS is still awaiting the sampling data results from EPA to conduct the public health assessment. Until environmental sampling data is received, BEHS cannot definitively state that people are being exposed to pentachlorophenol at levels that would result in adverse health effects.
Cancer Investigation and Health Outcome Data Review:
BEHS has never received the names of teachers at Idaho Hill Elementary School who are said to have cancer. To date, only anecdotal information about the numbers of people with cancer in the school and community has been received. BEHS has approached the school districts to try and obtain information about the teachers to compare to the Cancer Data Registry of Idaho's (CDRI) database. The school districts were reluctant to provide the key pieces of information (birthdates and social security numbers if available) necessary for the CDRI to conduct a meaningful cancer analysis for the school. The school districts were willing to provide CDRI with the names and dates of employment. However, the CDRI did not feel that the name identifiers alone could be effectively validated against their database because the chance of errors in matching individuals on name alone was too high. Because of privacy and confidentiality issues, BEHS and CDRI are not in a position to take the list of names and contact people individually to see whether or not they have been diagnosed with cancer in Idaho.
BEHS is currently conducting another cancer incidence analysis for the combination of three zip codes (Oldtown, Newport, and Priest River). The analysis results will be compared to the rates in both the remainder of the state of Idaho and the remainder of the county (rural area). BEHS will then evaluate over 24 cancer types, as well as all cancer types combined by gender. CDRI has a 99.6% case completeness rate and a 98.6% accuracy rate. In other words, BEHS has great confidence that those people in your communities that were diagnosed with cancer in Idaho or neighboring states are included in their database.
Lastly, BEHS is waiting for environmental data to provide evidence that an epidemiological study or biological testing (for example, urine, blood, or fat testing) is warranted. Unfortunately, there is no other comprehensive, non-cancer disease registry in the State of Idaho. BEHS will utilize the data that is currently available. Current efforts at the Federal level to begin tracking chronic diseases other than cancer may give local, state, and federal public health agencies more extensive health outcome data to use in the future.
Specific questions have been asked about the costs, invasiveness, and logistics of having body fat tested for the, presence of dioxin (impurity found in pentachlorophenol). BEHS does not recommend body fat testing for dioxin until environmental data support the need for such testing. However, BEHS has done some research and found that there are very few laboratories that have the ability to analyze body fat for dioxin. The laboratory analytical techniques are complicated, therefore the tests are expensive. The cost is dependent upon the number of samples submitted to the laboratory and the detection limit that is requested. An individual analysis is approximately $1,500. The amount of body fat that is required for analysis varies by analytical technique, but the approximate amount is 10 or more grams of body fat. The fat extraction process is dependent upon the physician, as well as the physician costs. ATSDR's toxicological profile for pentachlorophenol cites references that evaluated body fat testing for dioxin.
Use of the Term Health Effects:
BEHS and ATSDR use the term "health effects" to denote that there may be a change in the health status of an individual or an effect on health. The agencies judge that the terminology "health effect" is appropriately used in the BEHS health consultation and is consistent with how other public health agencies present information. BEHS does not feel that it implies a "healthy effect" from exposure to pentachlorophenol and did not assume that others would think that it implied a positive change in one's health status.
Use of the Term "Exposure" in Conjunction with "Potential:"
Until BEHS has received environmental sampling data identifying that contaminants are leaving the site resulting in off-site exposures, BEHS does not feel it is appropriate to eliminate the word "potential." BEHS, as a public health agency, can not definitively state there is exposure to pentachlorophenol or determine resulting impacts on human health without supporting environmental data.
Has Pentachlorophenol in the Air in Oldtown Reached Hazardous Levels? How do you determine what a hazardous level is?
As partners with ATSDR, BEHS uses Minimal Risk Levels (MRL's) to calculate non-cancer risk and adopts a cancer slope factor from EPA to calculate cancer risk. At or below that MRL and at or below calculated cancer unit risk, we consider the exposure to be without apparent risk of health effects.
The ATSDR toxicological profile for pentachlorophenol documents that the following MRL has been established: 0.005 mg/kg/day for acute-duration oral exposure and 0.001 mg/kg/day for both intermediate-duration and chronic-duration oral exposure. Currently there are no inhalation MRLs available for pentachlorophenol. However, oral data is used to assess inhalation exposure when inhalation data are not available, as in the case of pentachlorophenol.
EPA has developed an oral slope factor for pentachlorophenol, 0.12 (mg/kg/day)-1, based on a feeding study in mice conducted as part of the National Toxicology Project. Since there is no inhalation slope factor available for pentachlorophenol, BEHS adopted the EPA oral slope factor value as an inhalation slope factor to assess risk. BEHS is aware that there are uncertainties associated with using an oral factor for inhalation purposes. The State of California published an inhalation slope factor for pentachlorophenol, 0.018 (mg/kg/day)-1. It is not known if the California value more accurately represents the carcinogenic toxicity of pentachlorophenol than the EPA value. BEHS will use EPA's value to be more protective and to determine a site-specific risk-based ambient air concentration. In order to do so, the potential for exposure to pentachlorophenol via other exposure routes, such as dust inhalation, incidental soil ingestion, or dermal uptake, should also be evaluated. If there are other complete exposure pathways, then the acceptable concentration of pentachlorophenol vapor in air would have to be lower because other pathways also contribute to cumulative cancer risk. So far, BEHS does not have data from other environmental media needed to make a final decision.
Finally, BEHS is using the standard risk assessment/public health assessment procedures currently recommended by EPA and ATSDR, respectively. Pentachlorophenol is presently under EPA's review for a new oral cancer slope factor. As soon as that is finalized, BEHS will adapt the new EPA factor. ATSDR's MRLs were revised and published in September 2001. BEHS is confident it is utilizing the most up-to-date peer-reviewed science for conducting the public health assessment.
BEHS's Use of the Term "Weak" in Relation to Pentachlorophenol as a Carcinogen:
BEHS stated in its first health consultation for Oldtown that "there is weak evidence pentachlorophenol causes cancer in humans." On page five of the ATSDR Toxicological Profile for pentachlorophenol (both the draft document and the final September 2001 document) under the section titled, "How can pentachlorophenol affect my health," the following paragraph can be found:
"An increased risk of cancer has been shown in some laboratory animals given large amounts of pentachlorophenol orally for a long time. There is weak evidence that pentachlorophenol causes cancer in humans. The International Agency for Research on Cancer (IARC) has determined that pentachlorophenol is possibly carcinogenic to humans, and the EPA has classified pentachlorophenol as a probable human carcinogen."
The toxicological profile is a peer-reviewed profile that, as stated in the foreword, "identifies and reviews the key literature that describes a hazardous substance's toxicological properties." It also states that "this profile reflects ATSDR's assessment of all relevant toxicologic testing and information that has been peer-reviewed. Staff of the Centers for Disease Control and Prevention and other federal scientists have also reviewed the profile. In addition, this profile has been peer-reviewed by a nongovernmental panel and was made available for public review.' ATSDR, even after reviewing copious amounts of peer-reviewed literature, continues to use the same language. Additionally, after reviewing many animal studies and epidemiology studies, EPA classified pentachlorophenol as a "probable human carcinogen." The IARC classified it as "possibly carcinogenic to humans". Pentachlorophenol is not currently classified as a known "human carcinogen" because there are not enough human epidemiologic studies supporting the classification.
BEHS noted in one of the community meetings that IDEQ did not consider pentachlorophenol as a carcinogen when establishing Idaho's ambient air standard. That decision was a professional judgment made at that time. IDEQ is now considering revising Idaho's standard to err on the side of protection. However, decisions made by the State of Idaho do not influence the scientific data EPA or ATSDR utilizes.
The Banning of Pentachlorophenol:
BEHS is not in a position to ban the use and manufacture of pentachlorophenol. BEHS, like ATSDR, can only make recommendations. In Oldtown, BEHS has not seen evidence, to date, to support a position that pentachlorophenol use at Poles, Inc. is presenting a situation immediately dangerous to life and health. If that situation were found, BEHS could work with IDEQ and the Idaho Department of Agriculture to control the facility's use of the chemical. BEHS cannot ban the use and manufacture of a chemical.
EPA reevaluates all pesticides that were registered before November 1984. When EPA completes the review and risk management decision for a pesticide that is subject to reregistration, the Agency generally issues a Reregistration Eligibility Decision (RED) document. The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S. If pentachlorophenol is not eligible to be reregistered during its RED, IDEQ and BEHS will respond to that final decision accordingly.
BEHS anticipates that the public health assessment for the site will provide a comprehensive picture of the issues in Oldtown. No recommendations are indicated at this time. The public health assessment, due spring 2002, will evaluate the issues in Oldtown and provide public health recommendations.
BEHS, IDEQ, ATSDR, and EPA have conducted or are currently planning the following public health actions:
ATSDR 2001. Toxicological Profile for Pentachlorophenol (update). U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. Atlanta, GA.
BEHS 2001a. Evaluation of Potential Pentachlorophenol Air Contamination Based on the Idaho Department of Environmental Quality April 2001 Air Modeling Results. Poles Inc. Wood Treating Facility Oldtown, Bonner County, Idaho. Bureau of Environmental Health and Safety, Division of Health, Idaho Department of Health and Welfare, Boise, ID and Agency for Toxic Substances and Disease Registry, Atlanta, GA. August.
BEHS 2001b. Evaluation of EPA's Integrated Assessment Sampling and Quality Assurance Plan for Poles, Inc., EPA Contract No. 68-SO-01-01, TDD No. 01-07-0007 Poles Inc. Wood Treating Facility Oldtown, Bonner County, Idaho. Bureau of Environmental Health and Safety, Division of Health, Idaho Department of Health and Welfare, Boise, ID and Agency for Toxic Substances and Disease Registry, Atlanta, GA. August.
IDEQ 2001. Summary of Analysis: Ambient Air Impact of Pentachlorophenol from Poles, Inc. Idaho Department of Environmental Quality. Boise, ID.
PREPARERS OF REPORT AND CERTIFICATION
Preparers of Report
Elke Shaw-Tulloch
Manager
Mingyi Trimble, Sc.D.
Health Assessor/Toxicologist
Environmental Health Education and Assessment Program
Bureau of Environmental Health and Safety
Division of Health
Idaho Department of Health and Welfare
ATSDR Technical Project Officer
Gregory V. Ulirsch
Environmental Health Engineer
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Any questions concerning this document should be directed to:
450 W. State St., 4th floor
P.O. Box 83720
Boise, ID 83720-0036
208-334-6584
behs@idhw.state.id.us
The Idaho Bureau of Environmental Health and Safety prepared this Health Consultation under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation was initiated.
Gregory V. Ulirsch
Technical Project Officer, SPS, SSAB, DHAC
The Superfund Site Assessment Branch (SSAB), Division of Health Assessment and Consultation (DHAC), ATSDR has reviewed this health consultation and concurs with its findings.
Sven E. Rodenbeck
for Richard Gillig
Chief, SSAB, DHAC, ATSDR
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