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PUBLIC HEALTH ASSESSMENT

POLES, INCORPORATION WOOD TREATMENT FACILITY
OLDTOWN, BONNER COUNTY, IDAHO


5. DISCUSSION - ADULT AND CHILDREN'S HEALTH ISSUES

After reviewing the site-specific data and information, there are four completed and three potential exposure pathways which people could be or could have been exposed to chemicals from the site. Health effects can only result from site contaminants when people come in contact with them. The public health implication of the exposures is discussed in the following sections. In Section 5.1, the actual exposures or doses to these contaminants of concern (selected from Section 3) are evaluated using estimates of exposure and the toxicological properties and epidemiological information of these chemicals. As a part of the ATSDR Child Health Initiative and in response to community concerns, the susceptibility of young children or developing fetuses to the chemical exposures are part of the toxicological and epidemiological review. In Section 5.2, cancer incidence data for the combined ZIP Codes of Oldtown, ID, Newport, WA, and Priest River, ID are presented. Finally, questions raised by the community during the public health assessment process are presented and addressed in Section 5.3.

5.1 Public Health Implications

5.1.1 Introduction

In order to understand the health effects that may be caused by a specific chemical, three factors affecting how the human body responds to exposure need to be considered. These factors include exposure concentration, the duration of exposure, and the route of exposure. Lifestyle factors can affect the likelihood of exposure and the exposure duration. Individual characteristics of each human such as age, sex, nutritional status, and overall health can affect how a contaminant is absorbed, distributed, metabolized or eliminated from the body. Together, these factors determine the individuals' response to chemical contaminants and what health effects may occur for that person.

To evaluate health effects, ATSDR developed MRLs for contaminants commonly found at hazardous waste sites. The MRL is an estimate of daily human exposure to a contaminant below which non-cancerous, adverse health effects are unlikely to occur. MRLs are developed for each route of exposure, such as inhalation and ingestion, and for the length of exposure, such as acute (less than 14 days), intermediate (15-364 days), and chronic (greater than 365 days). Acute MRLs are typically higher than chronic MRLs because of the shorter duration of exposure. BEHS also uses EPA's chemical-specific RfDs to determine if non-cancer health effects are possible. RfDs, similar to ATSDR's MRLs, are estimates of daily human exposure to a contaminant that is unlikely to result in adverse non-cancer health effects over a lifetime. For chemicals that are considered to be known, probable, or possible human carcinogens, BEHS uses EPA's chemical-specific cancer slope factors to calculate a theoretical excess lifetime cancer risk. These risks are associated with the exposures that are based on conservative (protective) exposure assumptions. The cumulative cancer risk from exposure to multiple environmental media and multiple site-related contaminants were added together for a total risk estimation. BEHS assumes an additive effect among mixtures of chemicals.

For determining possible exposures to contaminants in soil, maximum surface soil concentrations were used. The exposure scenarios for children were based on an older child (Elementary school age, 7 years or older) playing at the Oldtown site and a young child (1-6 years old) playing in private yards. BEHS assumed that younger children are more closely supervised and would not wander onto the site. It was also assumed that older children would not spend more than three days playing onsite per week and young children would spend time outdoors everyday in private residential yards. For adults, BEHS assumed two exposure scenarios. One was for a site employee who worked for Poles, Inc. for approximately 20 years and the other scenario was for an adult resident living near the site who occasionally visited the site for recreational or personal purposes. Adults living near the site would not spend more than one day a week visiting the site. People reduce outside activities during the cold winter months and have less contact (or no contact) to surface soil. BEHS assumes people are not exposed to surface soil because of snow cover and decreased outdoor activities for three months a year.

Exposure duration, body weight, and age are used to estimate the amount of contaminants that might have entered a person's body. For example, young children between the ages of 1 - 6 years old are known to put almost anything in their mouth, including soil (pica behavior). This behavior increases their chances of exposure to soil contaminants. The assumptions used to calculate exposure for young child are a body weight of 15 kg (approximately 30 pounds) with an ingestion rate of 5000 milligrams (mg) of soil per day. The assumptions for an older child (7 -18 years of age) are a body weight of 45 kg (approximately 100 pounds) and a soil ingestion rate of 200 mg per day. The assumptions for an adult are a body weight of 75 kg (approximately 165 pounds) and a soil ingestion rate of 100 gram per day. Those estimates were chosen in reference to the Exposure Handbook (EPA 1997) and ATSDR's guideline with some Idaho-specific adjustments. According to EPA, young children accidentally eat approximately 150 mg of soil a day. BEHS uses ATSDR's conservative (protective) suggestion of 5000 mg/day (approximately one teaspoon) for young children with pica behavior. Instead of the standard EPA body weight assumption (70kg), BEHS uses the median Idahoan body weight of 75kg to better represent people in Idaho (BVRHS 2001). In addition, the maximum concentration found in surface soil was used for calculating risks and doses, so a worst case scenario was evaluated.

To determine possible exposure to contaminants in air, maximum air sampling concentrations were used to calculate risks and doses to be protective of public health. The inhalation rate assumptions used to calculate exposures are 10 cubic meters of air per day (M3/day) for children less than 6 years of age, 15 M3/day for order children between ages 7 and 18, and 20 M3/day for adults. BEHS assumes that people are living around the Oldtown site for 30 years out of an average 70 year lifetime and people are exposed to the air contaminants 40 to 120 days of the year (Poles, Inc. operates once per week for 9 months of a year/ assuming air contaminants persist in air for 1 - 3 days).

For determining possible exposure to contaminants in drinking water, maximum contaminant concentrations found in groundwater samples were used to calculate risks and doses to be protective of public health. Water consumption rates are assumed to be 1 liter per day (L/day) for children less than 6 years old and 2 liters per day for children aged 7 through adults.

All assumptions are summarized in the following table.

Table 6.

Exposure Assumptions Summary
Exposure AssumptionsPopulationa
Children <7 7<Children<18 Adults > 18 Workers
Body Weight (kg)15 45 75 75
SoilIngestion Rate (mg/kg)

5000

200 100 100
Exposure Frequency

daily offsite

3 days/week onsite 1day/week onsite 5 days/week
AirInhalation Rate (M3/day)

10

15 20 20
Exposure Frequency 40 -120 year
WaterConsumption Rate (L/day)

1

2
Exposure Frequency

daily

Years of Exposureb

6

12 12 20

a: assume average lifetime is 70 years
b: assume people live in Oldtown for an average of 30 years

Once an exposure is determined based upon the previous exposure assumptions, BEHS assignsthe exposure pathway a health hazard category, as developed and defined by ATSDR. Thecategories include: 1) urgent public health hazard, 2) public health hazard, 3) indeterminatepublic health hazard, 4) no apparent public health hazard, and 5) no public health hazard. A listof these public health hazard categories and their descriptions can be found in Appendix K. These health hazard categories are utilized by ATSDR and its cooperative agreement states toensure a consistent approach among public health assessors nationwide and to ensure that siteswithin each state are consistently evaluated.

5.1.2 Evaluation of Toxicology and Epidemiology by Pathway

Two major completed exposure pathways (onsite surface soil and air) that have elevated site-associated contaminants are evaluated in detail. The potential effects of each chemical arediscussed individually; the combined effects of multiple chemicals are evaluated; any specialchild health issues related to the exposures are discussed; and there is an overall summary of thepublic health implications of the pathways. The remaining completed exposure pathways(offsite surface soil and sediment at the Pend Oreille River) and the potential groundwaterexposure pathway are discussed. Even though arsenic is not a site related issue, arsenic exposureis evaluated and discussed in a separate section.

5.1.2.1 Onsite surface soil pathway

Based on IDEQ's surface soil sampling, the START IA and the START dioxin/furan sampling,site-related contaminants were found in onsite surface soil. Six site-related contaminants andbackground arsenic were found at levels greater than health comparison values. Workers andtrespassers (nearby residents or school children) may be exposed. The estimated daily averageexposure doses were calculated with site-specific exposure assumptions and the maximumconcentrations of each contaminant that exceeded the health comparison values. The results arepresented in Table 7. The detailed calculations and equations are summarized in Appendix I. Age-adjusted soil ingestion rates were used for dose estimations to account for children's hand-to-mouth behavior.

Table 7.

Estimated Lifetime Exposure from Onsite Surface Soil Pathway
Compound Max. Conc. (mg/kg)a Estimated Exposure (mg/kg/day)b,c Dose Comparison - MRL (mg/kg/day)
Benzo(a)anthracene

0.77

0.00000021 --
Benzo(b)fluoranthene

1.64

0.00000044 --
Benzo(a)pyrene

0.615

0.00000017 --
Dibenz(a,h)anthracene

0.125

0.000000034 --
Ideno(1,2,3-cd)pyrene

1.28

0.00000034 --
Pentachlorophenol

600

0.00016 0.001
Background Arsenic

15

0.000002 d 0.0003

a: The maximum concentrations reported from IDEQ and START IA
b: Exposure assumption for dose calculation are listed in section 5.1.1 Table 6
c: Detail calculation equations can be found in Appendix I, Equation 1
d: BEHS has applied an addition bioavailability factor for calculation of background arsenic exposure, see section 5.1.2.5
--: MRL is not available. Cancerous effects discuss in the following section

Adverse health effects have been observed in humans and experimental animals following short-and long-term exposure to penta by inhalation, oral, and dermal exposures. Long-term exposureto technical-grade penta can cause damage to the liver, kidneys, blood, and nervous system. Some of those effects may be caused by chlorinated dibenzo-p-dioxin (dioxin) or otherimpurities in technical-grade penta. The impurities are unavoidable during the pentamanufacturing process. Symptoms of human exposure to penta treated wood include severe skinblisters and rashes. These skin effects may be due to penta impurities. The toxic effects of pentaappear to be most serious following high-dose, acute exposure. There are no human studies thathave demonstrated a reproductive toxicity of penta. However, there are animal studies that haveshown adverse reproductive and developmental effects. Fetuses, infants, and children may bemore susceptible to the effects of penta.

The estimated accidental onsite soil exposure to penta from playing/living around Oldtown sitefor 30 years was 0.00016 milligrams of penta per kilogram body weight per day (mg/kg/day)over a lifetime. This level does not exceed the chronic penta MRL of 0.001 mg/kg/day. Schoolage children playing occasionally onsite would be exposed to 0.00085 mg/kg/day over the courseof a year. This level does not exceed the acute MRL of 0.005 mg/kg/day or intermediate MRLof 0.001 mg/kg/day. When the dose is less than an MRL, adverse non-cancer health effects arenot expected as a result of exposure.

In the case of penta, the chronic MRL was based on a multi-generation reproductive study. TheLowest Observed Adverse Effect Level (LOAEL) was 1 mg/kg/day where female sheep had achange in thyroid function. The chronic MRL was derived by dividing the LOAEL by anuncertainty factor of 1000 (10 for use of a LOAEL, 10 for interspecies extrapolation, and 10 forhuman variability). Applying an uncertainty factor is a standard toxicological risk assessmentapproach to be conservative and protective of human health (IRIS 1987).

A number of animal studies suggest that penta may cause cancer in humans. No convincinghuman epidemiological evidence has demonstrated that penta causes cancer in humans. Casereports suggest a possible association between cancers and occupational exposure to technical-grade penta that includes impurities (ATSDR 2000a). These cancers include Hodgkin's andnon-Hodgkin's lymphoma, soft tissue sarcoma, and acute leukemia. Penta is classified as aprobable human carcinogen (Group B2) by EPA. The cancer risk resulting from onsite surfacesoil exposure to penta is combined with other chemical exposures which may contribute tooverall cancer risk. The following paragraphs describe cancer risk estimation from exposure tothe mixtures of Oldtown site surface soil contaminants.

Additionally, there are five PAHs detected in onsite soils that have concentrations greater thanthe comparison values. PAHs are a group of structurally related compounds with similarchemical and physical characteristics. PAHs are part of the emissions from heating the poletreatment oil. There are more than 100 different PAH compounds which generally do not occuralone. Exposure to a mixture of PAHs through accidental ingestion of onsite contaminated soilby workers and trespassers may occur.

Animal studies show that PAHs could cause harmful effects on skin, in body fluids, and on theimmune system after short- and long-term exposure. However, those effects have not been seenin humans. Skin contact with certain PAHs may cause deleterious skin conditions. People withpre-existing skin problems may be more sensitive to the adverse dermal effect of PAHs. Themostly likely exposure routes in a work environment are through inhalation and skin contact. This is of particular concern for workers who come into direct contact with the PAH-containingmaterial. Occupational studies of workers provide some evidence that PAH exposure mayincrease cancer incidence. The five PAHs found at the Oldtown site were benzo(a)anthracene,benzo(b)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, and ideno(1,2,3-cd)pyrenewhich are classified as "probable human carcinogens" by EPA (ATSDR 1995).

To determine the cancer risk from exposure to surface soil at Poles, Inc., the cancer riskscontributed from penta and PAHs are added together. For PAHs, the relative potency ofcarcinogenic PAHs is added together as benzo(a)pyrene equivalents because benzo(a)pyrene isknown to be the most potent among PAHs (IRIS 1994 a,b,c,d,e). Using the maximumconcentration in onsite surface soil, BEHS estimated a 2 x 10-5 risk of developing cancer fortrespassers and workers at Poles, Inc. This means two additional cases of cancer out of 10,000people may be attributed to the site related exposure. Realistically, for communities such asOldtown where the exposed population is low, people do not expect to develop cancer due tosite-related exposures. Furthermore, the estimated excess cancer risk is likely to overestimatethe risk of cancer because it is based on the maximum level of penta and PAHs detected insurface soils. It is more likely that long-term exposures occur to the average concentration ofpenta and PAH's, not to the maximum values.

BEHS does not expect trespassers and workers to get ill from exposures to contaminants inonsite surface soils at the levels in which they are present. Exposure to onsite surface soil isoccurring and can occur, but not at levels expected to cause health effects. As a prudentprecaution, BEHS recommends further public health actions be taken at the site to eliminate thepossibility of exposure. Recommendations and the public health action plans are discussed inSections 7 and 8.

5.1.2.2 Air Exposure Pathway

Based on the START IA air sampling results, 11 site-related contaminants were found in airaround the site. Penta was the only compound found at levels greater than the health comparisonvalues. Nearby residents, students, workers, and trespassers could have been exposed to pentathrough the air pathway during the wood treatment process. In general, higher pentaconcentrations were detected outdoors close to the treatment area. Penta was not detected in anyof the three indoor air samples from the school. The maximum concentration of penta was usedto estimate the daily average exposure doses in order to be the most conservative (protective). The dose calculation has considered an age-adjusted factor to account for the higher respiratoryrates of children.

The estimated dose from exposure to penta in air from the Oldtown site for 30 years was 0.00003to 0.00008 mg/kg/day over a lifetime. These levels do not exceed the chronic and intermediatepenta MRLs of 0.001 mg/kg/day. When the dose is less than an MRL, adverse non-cancer healtheffects are not expected as a result of exposure.

Penta is classified as a "probable human carcinogen" (Group B2) by EPA, however, EPA has notpublished an inhalation cancer slope factor for penta. The current penta oral slope factor is 0.12(mg/kg/day)-1 based on a mouse study in which male mice exposed to penta orally developedliver tumors. The animal dose was extrapolated to a human dose equivalent. A slope factor wascalculated using a linearized multistage model that was known to be the most conservative(protective) model. The State of California published an inhalation slope factor for penta, 0.018 (mg/kg/day)-1, based on the same mouse study. It is not known if the California value moreaccurately represents the inhalation carcinogenic toxicity of penta than the EPA value. Sincecancer risk is calculated by multiplying the dose by the cancer slope factor, the higher the cancerslope factor the higher the caner risk estimate. California's value is less conservative than usingEPA's oral value. BEHS adopted EPA's oral value rather than California's inhalation value toassess risk to be more protective of public health. BEHS is aware that there are uncertaintiesassociated with using an oral factor for inhalation purposes.

BEHS used the maximum penta concentration detected in air as well as site-specific exposureassumptions to calculate an estimated cancer risk. Exposures to penta through the air pathwayduring Poles, Inc. most recent treatment processes does not significantly increase the risk ofdeveloping cancer for the communities around the site. This conclusion concurs with ATSDR'sevaluation stated in a health consultation to the EPA START (ATSDR 2001) (Appendix J). Pastexposure, prior to emission control improvements, may have been higher and posed a publichealth hazard, however, it is not possible to estimate the past exposure. Poles, Inc. is no longertreating poles at the site.

5.1.2.3 Potential Groundwater Exposure Pathway

START, during the IA, found penta and 12 site-unrelated heavy metals in groundwater at levelsgreater than the comparison values. EPA does not know whether the private wells draw waterfrom the same aquifer as the EPA's monitoring wells. Therefore, the potential impact to theprivate wells cannot be estimated. There are 46 domestic wells within a 1-mile radius and 484domestic wells within a 1- to 4-mile radius of the site. Since none of the private wells are downgradient of the site, the contaminants are unlikely to impact the private wells. According toEPA, the primary drinking water source for most residents in Oldtown is the municipal watersupply that draws water from surface water upstream of the Poles, Inc. site. BEHS evaluatedboth penta and the heavy metal contamination in groundwater and summarizes the results in thefollowing paragraphs. Heavy metal contamination is not a site-related issue. Dioxin and furancontamination will be evaluated further when information about the groundwater pathway isavailable.

To be conservative or protective, the maximum concentration of penta in groundwater was usedto estimate the daily average doses. The dose estimation incorporated the age-adjusted factor toinclude the appropriate water consumption per body weight for children. If exposure did occur,the estimated dose of penta from consuming contaminated groundwater for 30 years is 0.00068mg/kg/day. This level is lower than the chronic MRL of 0.001 mg/kg/day, therefore, it isunlikely that a non-cancerous health effect would result from penta exposure by consumingcontaminated groundwater.

For heavy metals, BEHS first compared the maximum groundwater concentrations to multipledrinking water criteria. Since some of the drinking water criteria were established for reasonsother than health, BEHS estimated a daily average exposure and compared it to health-basedcriteria, MRL and RfD. The results are summarized in Table 8.

Table 8.

Estimated Lifetime Exposure from Groundwater Pathway (if exposure occurred)
Compound Max. Conc. (mg/L) Water Quality Criteria - MCL (mg/L) Estimated Lifetime Exposure (mg/kg/day) Dose Comparison - MRL or RfD (mg/kg/day)
Pentachlorophenol

0.046

0.001 0.00068 0.001
Aluminum

115

0.05 - 0.2 a 1.7 2
Antimony

0.014

0.006 0.0002 0.0004
Arsenic

0.344

0.01b 0.0051 0.0003
Barium1.97 2 0.029 0.07
Beryllium

0.009

0.004 0.00013 0.001
Chromium

0.214

0.1 c 0.003 0.003
Cobalt

0.199

-- 0.003 0.01
Iron

298

0.3 a 4.4 --
Lead

0.327

0.015 d 0.0049 --
Nickel

0.174

0.1 e 0.0026 0.02
Thallium

0.017

0.002 0.00026 --
Vanadium

0.297

-- 0.0044 0.003

a: Secondary Drinking Water Regulation
b: Proposed MCL to be implemented in 2003
c: Total Chromium MCL
d: Action Level
e: Lifetime Health Advisory for drinking water
Gray areas represent the maximum concentrations that are higher than the water quality criteria or the estimated exposure doses that are higher than the MRL or RfD.

The maximum concentrations of nine out of 12 heavy metals were higher than the drinking watercriteria. The estimated lifetime exposure to arsenic and vanadium is greater than the chronicMRL. The details for arsenic exposure are discussed in Section 5.1.2.5. Vanadium is anessential nutrient of the human body. The body's nutritional requirement for vanadium is verylow and can be easily met by levels naturally occurring in foods, water, and air (average intakefor adult 10-20 µg/day) (NRC 1989). Laboratory animals fed diets extremely low in vanadiumshowed depressed growth and impaired reproductive performance. People exposed to 0.47-1.3mg vanadium per kilogram of body weight experienced gastrointestinal distress. Long-termanimal studies (2.5 years) showed a decrease in the amount of cystine in hair (brittle hair) afteringesting vanadium (IRIS 1996, ATSDR 1992). The upper limit of the recommended dietaryallowances for adult is 1.8 mg/day (approximately 0.024 mg/kg/day). The estimated lifetimeexposure to vanadium (0.0044 mg/kg/day) from using contaminated groundwater is lower thanthis upper limit. Therefore, BEHS does not consider vanadium a health risk even whencalculated dose levels are added to the normal daily diet.

The cumulative cancer risk from using contaminated groundwater was calculated by addingcancer risk contribution from antimony, arsenic, chromium, and penta. BEHS estimates thatthere may be an increased risk of developing cancer if people are exposed to contaminatedgroundwater. It is important to note, however, the majority of the estimated cancer risk was notattributable to the site-related penta contamination, rather to the heavy metals.

The groundwater exposure pathway cannot be fully established (only a potential pathway). It isnot known if domestic wells are drawing groundwater from the same aquifer as EPA'smonitoring wells or if private wells are impacted by the groundwater contamination onsite. Since none of the private wells are located down gradient of the Oldtown site (EPA 2002a), thewells are not likely to be impacted. However, domestic wells were not sampled during theSTART IA and the exposures cannot be determined. The potential for groundwater to impactpeople exists after review of the groundwater contamination levels. Therefore, BEHSrecommends further action be taken at the site to collect more information about the pathway. The recommendations and planned public health actions regarding groundwater are discussed inSections 7 and 8.

5.1.2.4 Other Exposure Pathways

Other exposure pathways were identified by BEHS as having less public health significance. They are briefly described in the following paragraphs.

EPA detected heavy metals, chlorinated pesticides, SVOCs, and VOCs in offsite surface soil. Afew SVOCs and VOC were detected in sediment in the Pend Oreille River. Arsenic, attributedto background levels, was the only chemical found at levels greater than the comparison value. The concerns about background arsenic exposure are discussed in the next section (5.1.2.5). Nearby residents, people in school, recreational sportsmen and children playing along the PendOreille River are not currently exposed to site-related contamination at levels that may causeharm. Higher exposure in the future is unlikely.

A potential exposure pathway exists for sportsmen and children who come in contact withsurface water from boating, fishing or playing in the Pend Oreille River. The other potentialexposure pathway exists for individuals who consume biota such as fish or other aquaticorganisms caught/collected in the River. Surface water and fish were not sampled; however,BEHS does not recommend further actions because exposure though these pathways is unlikelyand BEHS does not expect people to get ill. Additionally, exposure to onsite subsurface soilcontamination and indoor dust contamination is unlikely and BEHS does not consider thesepathways of public health concern.

5.1.2.5 Background Arsenic Exposure

Arsenic exists naturally in soils and rocks. Commercial products containing arsenic include, butare not limited to, wood preservatives, pesticides, paints, and leaded gasoline. Poles, Inc. hasnever used arsenic products to treat wood at this facility (EPA 2002a). Certain industrialactivities that release arsenic are desulfuring of gases and/or fossil fuels, burning preservedwood, and metal alloy production. Volcanic eruptions are another source of arsenic. Arsenicwas used historically in certain medicines such as anti-syphilis drugs. There are two forms ofarsenic in the environment, organic and inorganic forms. The inorganic forms are usually moretoxic than organic ones. The normal analytical method for arsenic does not distinguish thespecific form of arsenic (ATSDR 2000b). To ensure a conservative or protectivetoxicological/public health estimate, BEHS assumes all the arsenic detected by START isinorganic arsenic.

Studies show that swallowing a small amount of inorganic arsenic may cause stomach irritationand a decreased blood cell count. The decreased blood cell production may cause fatigue,abnormal heart rhythm, blood vessel damage resulting in bruising, and impaired nerve functioncausing a "pins and needles" sensation in hands and feet. Long-term exposure may lead to"Blackfoot disease" which is a condition in which blood circulation is lost which ultimatelyleads to hands and feet necrosis (cell death). The most characteristic effect of long-term oralexposure to arsenic is a pattern of skin changes. These include darkening of the skin andappearance of warts on the palms, soles, and upper body. Some of the warts may ultimatelydevelop into skin cancer. Inorganic arsenic is classified as a "known human carcinogen" byEPA. Exposure to arsenic may increase the risk of liver, bladder, kidney, prostate, and lungcancers.

The human body absorbs different forms of arsenic differently depending on the environmentalmedia in which it is contained. Arsenic in soil is harder to absorb than the commonly foundsoluble arsenic forms in drinking water. Studies show that arsenic in soil below 40% can beabsorbed by the human body once ingested. This is important for calculating human doses. Thecurrent arsenic soil CREG (cancer risk evaluation guide) is 0.5 mg/kg that BEHS uses as ascreening tool to identify contaminants of concerns. The CREG is a theoretical calculation thatassumes a consumption of 100 mg/day by a 70 kg person over lifetime without consideration ofthe absorption rate. Another similar approach results in a similar comparison value of 0.6 mg/kgby assuming that a child (forever remaining at 10kg) consumes 5000 mg soil everyday over a 70year lifetime. Obviously, both scenarios are not plausible and the present comparison value islikely to be overly conservative.

People can be exposed to arsenic from the environment by eating food, drinking water, orbreathing air. Children, particularly younger children with a tendency of putting hands in theirmouth, may be exposed to more arsenic from eating dirt. Skin contact with soil or water thatcontains arsenic may be another exposure route. As described throughout this public healthassessment, background arsenic levels were found in surface soil (5.7 - 15 mg/kg), subsurfacesoil (6.9 - 16.9 mg/kg), and sediments (5.2 - 5.7 mg/kg). Elevated arsenic (0.15 - 0.34 mg/L)was found in groundwater samples. The site-specific background arsenic levels were 9.7 mg/kgin surface soil and 9.1 mg/kg in the upper and 7.8 mg/kg in the lower portion of the subsurfacesoil, and 5.3 mg/kg in sediment. The maximum concentration in the offsite surface soil (9.7mg/kg) is used for estimation of daily exposure. BEHS considered the bioavailability of arsenicfrom soil to be 50%. Age-adjusted soil ingestion rates were used to calculate lifetime arsenicdose (see Appendix I). The average lifetime daily exposure for people living around theOldtown site for 30 years is 0.00011 mg/kg/day. This value is lower than the chronic MRL of0.0003 mg/kg/day. Young children with pica behavior playing in the residential yard daily havean estimated exposure dose of 0.0012 mg/kg/day over the course of a year. The shorter-term(within a year) exposure should be more appropriately compared to the intermediate or acuteMRL. This level is lower than the ATSDR provisional acute MRL for arsenic of 0.005mg/kg/day.

After reviewing many human studies, as reported in ATSDR Toxicological Profile for arsenic,the lowest arsenic Cancer Effect Level (CEL) for lung cancer is 0.0011 mg/kg/day; for bladdercancer is 0.033 mg/kg/day; and for skin cancer is 0.0075 mg/kg/day. The average lifetimeexposure dose (0.00011 mg/kg/day) is lower than the lowest CELs of arsenic. BEHS does notexpect elevated cancer risk from exposure to background arsenic.

5.1.2.6 Summary

People may be exposed to contamination in onsite surface soil but the exposure levels were lowand health effects were not expected (see 5.1.2.1). Current and future exposures to air (5.1.2.2),sediment, and offsite soil (5.1.2.4) are not likely to result in adverse health effects. Thegroundwater (5.1.2.3) pathway was not positively identified or the point of exposure was notsampled, therefore it is considered an incomplete exposure pathway. Potential exposures topenta from surface water and biota are not considered likely because of the levels of penta foundin sediment and because of the physical nature of penta (5.1.2.4). People are not exposed toonsite subsurface soil and indoor dust. Background exposure to arsenic through accidentalingestion of soil is not an immediate health concern. However, even though BEHS does notexpect people to become ill as a result of the site, BEHS as a prudent public health practicerecommends actions be taken to further reduce exposures, particularly for younger children, andto better clarify the issues. The recommendations and suggested public health actions arediscussed in Sections 7 and 8.

5.1.3 ATSDR Child Health Initiative

Children differ from adults in their physiology (e.g., respiratory rates relative to body weight),pharmacokinetics (i.e., distribution, absorption, metabolism, and excretion of chemicals), andpharmacodynamics (i.e., susceptibility of an organ to the exposure). Therefore, it is alwaysimportant to address chemical exposures of these sensitive populations. Fetuses, infants, andchildren are more vulnerable to the toxic effects of chemicals because of the following reasons: 1) children are more likely to play outdoors and bring food into contaminated areas; 2) childrenare closer to the ground (shorter), resulting in a greater likelihood to breathe dust, soil, and heavyvapors laying on the ground; 3) children weigh less resulting in higher doses of chemicalexposure per body weight; and, 4) the developing body system can sustain permanent damage iftoxic exposures occur during critical growth stages.

For penta, dioxins/furans, and PAHs, animal studies show adverse reproductive anddevelopmental effects. Fetuses, infants, and children may be more susceptible to the effects ofpenta and PAHs. At the Oldtown site, using the highest onsite surface soil penta concentrations,the soil ingestion exposure did not exceed ATSDR's MRL. ATSDR does not have MRLs forskin or inhalation exposures to penta, therefore, it is difficult to determine the health effects fromskin contact or inhalation exposure. Younger children who have pica behavior were assumed tonot have contact with the site. Workers and trespassers who have young children at home shouldtake precaution to not track onsite soil into their home. It is a concern for young children whocome in contact with the site. BEHS's recommendations are summarized in Section 7.

5.2 Health Outcome Data Evaluation

5.2.1 Data Review

The potential for exposures to chemicals to result in adverse health effects are determined byseveral factors. These include: the toxicity of the chemical, the route of exposure (eating,breathing, and skin contact), the amount of exposure, and the duration of exposure. BEHSevaluated all of these factors during the public health assessment process. The potential for non-cancer health effects, such as effects on the fetus and reproduction, were evaluated. Thepotential for cancer was also considered. Worst case, site-specific exposure doses werecalculated and used in the public health assessment. Based on this evaluation, BEHS concludedthat present exposures are not occurring at levels high enough to result in non-cancer healtheffects. No conclusions can be drawn about past exposure.

The public health assessment process uses multiple methods to assess potential impacts incommunities. In addition to the evaluation described above, BEHS was able to examine actualdata about cancer cases in residents of Oldtown and nearby communities. Surveillance for non-cancer health effects are not currently available. Therefore the health outcome data evaluationfrom the Oldtown site is based on an analysis of available cancer data from the CDRI.

CDRI is a program of the Idaho Hospital Association that contracts with Idaho Department ofHealth and Welfare to provide a statewide cancer surveillance system. The Registry is apopulation-based cancer registry that collects incidence and survival data on all cancer patientswho reside in the State of Idaho and/or are treated for cancer in the State of Idaho. Throughcollaborative efforts with Idaho's neighboring states, CDRI is able to obtain cancer cases ofIdaho residents diagnosed and/or treated for cancer in adjacent states. CDRI has been inoperation since 1969 and the registry became population based in 1971. Each Idaho hospital,outpatient surgery center, and pathology laboratory is responsible for reporting cancer diagnosesand treatments within six months after services are provided. CDRI has a 99.6% casecompleteness rate and a 98.6% accuracy rate. In other words, BEHS has great confidence thatpeople in Oldtown and nearby Idaho communities that were diagnosed with cancers in either theState of Idaho or Washington are included in the CDRI's database. For residents of Newport,WA, information on cancer incidence was obtained from the Washington State Cancer Registry.

The period selected for each evaluation of the cancer incidence data was 1991 or 1992 - 1999. This is the most recent data available for ZIP Code analysis (Washington data begins in 1992). Cancer incidence was reviewed for this public health assessment instead of cancer mortalitybecause cancer death rates are affected by how advanced the cancer was at the time of diagnosis,access to health care and other factors not related to exposure. The cancer rates were comparedto the remainder of the State of Idaho.

5.2.2 Data Analysis

CDRI performed the initial cancer incidence evaluation for the ZIP Code of Oldtown (83822)between 1991 and 1999 and found the reported 24 cancer types were all within or lower thantheir expected ranges (Attachment D, Table D-1). Since Oldtown is a relatively smallcommunity people commute to Oldtown for work or school from different communities or ZIPcodes. CDRI could not rule out the possibility of underestimating the risk (Johnson 2001).

With help from the communities, BEHS was able to better identify the potentially impactedpopulation around Poles, Inc. The Idaho Cancer Analysis Working Group (CAWG) requestedthat CDRI perform another cancer incidence analysis for the Oldtown area. CAWG is comprisedof the Idaho State Epidemiologist and representatives from CDRI, the Bureau of Vital Recordsand Health Statistics, and BEHS. The new analysis for the Oldtown area included Oldtown andPriest River, Idaho and Newport, Washington combined ZIP Codes (1992 - 1999). Newport,WA is immediately adjacent to Oldtown and practically shares the same business district. CDRIwas able to gather data from the State of Washington to conduct this ZIP Code analysis. PriestRiver is a city six miles east of Oldtown. Many residents in Priest River commute to Oldtownfor school or work. BEHS is aware of the potential to underestimate cancer incidence associatedwith the site by including a larger population who might not have a relationship with the facility. However, concerned citizens repeatedly identified this potentially impacted population. Additionally, a combined ZIP Code evaluation included selected cancer sites that arebiologically plausible as a result of site-specific and selected non site-specific exposures. Theresults of this cancer incidence evaluation are the primary focus of this public health assessmentand are described in Section 5.2.3.

Cancer incidence for ZIP Codes 83822, 83856, and 99156 combined, corresponding to Oldtown,Priest River, and Newport, was calculated by comparing the observed number of cases to theexpected number of cases (also known as standardized incidence ratio). The expected numberwas calculated by multiplying rates for the remainder of Idaho and the population of thecombined ZIP Codes. The rate for the remainder of Idaho was calculated by dividing theobserved cases by the person-years for the remainder of Idaho. Person-years were estimated bysumming population estimates for the ZIP Codes over the time period of the study.

To help interpret the differences, the "statistical significance" of the difference is calculated. "Statistical significance" for this public health assessment means that there is less than a 5%chance that the observed differences are due to random chance alone (p<0.05). In other words, ifthe differences were found to be statistically significant, then the difference between theexpected and observed cases is probably due to some set of factors that influences the rate of thatdisease. It could be environmental factors, lifestyle factors, and/or family histories. In the publichealth assessment, only statistically significant differences are discussed.

Cancer is not a single disease. It is a group of more than 200 different diseases. Because canceris, unfortunately, a common disease (one of every three of us will develop cancer in ourlifetime), every community will experience a certain number of cancers. Different types ofcancer have different causes and are likely to be linked to different risk factors. Therefore,BEHS selected the specific cancer types that are biologically plausible as a result of pentaexposure according to scientific studies. Those specific cancers are Hodgkin's lymphoma, non-Hodgkin's lymphoma, acute leukemia, and soft tissue sarcoma. Arsenic is not a site relatedissue; nevertheless, BEHS evaluated the biologically plausible cancer sites that might relate toarsenic. Those cancer sites include bladder, kidney, liver, lung, skin, and possibility prostate.

In addition to the cancer evaluation for the general community members, BEHS attempted toconduct a cancer incidence evaluation targeting past and current teachers and staff of the IdahoHill Elementary School. The first attempt to gather the names and personal information (e.g.,social security number) from the school district was not successful (Appendix L). BEHS andCDRI are currently evaluating other possibilities.

5.2.3 Results of Cancer Incidence Analysis

Overall, cancer incidence in the combined ZIP Code area was not statistically significantlydifferent from that in the remainder of Idaho. There were, however, statistically fewer casesobserved (289) than expected (330) among males; about 12 % fewer cases than the remainder ofIdaho (Appendix D, Table D-2).

For the four selected cancers that might be associated with penta exposure, there weresignificantly more sarcoma cases observed than expected when compared to the remainder of theState (Appendix D, Table D-3). Seven sarcoma cases were observed while two cases wereexpected for the combined ZIP Code area. Soft tissue sarcoma may be associated with pentaexposure. Sarcoma is a rare form of tumor. Some risk factors for sarcoma include previousradiation therapy, exposure to chemicals (e.g., vinyl chloride, agent orange), immunodeficiency,chronic tissue irritation, and/or genetic influence.

For the six selected cancers that might be associated with background arsenic exposure, therewere significantly more female lung and bronchus cancers and fewer prostate cancers comparedto the remainder of the State (Appendix D, Table D-4). Lung cancer and prostate cancer arecommon cancers that have well established risk factors. The single most important risk factor inthe development of lung cancer is cigarette smoking. Prostate cancer is related to older age,family history, and ethnic group/country of residence.

Currently, it is not possible for BEHS to determine the association between exposure to site-related contaminants and the cancer incidence outcome. The influence of established risk factorsfor each type of cancer was not evaluated. This screening helps to identify the unusual patternsof adverse health effects and to direct future public health actions. CAWG recommends thatCDRI follow up with the sarcoma cases to better identify other possible risk factors associatedwith the disease. The potential site-related relationship needs to be investigated and interpretedwith caution. The suggested public health actions for this recommendation are discussed inSection 8.

5.3 Questions from the Community

When performing any public health assessment, BEHS gathers health concerns from peopleliving in the vicinity of the site. The concerns that people expressed are used to direct the focusof the public health assessment so that questions from the community are answered. At thePoles, Inc. Oldtown site, BEHS has collected community questions through the followingactivities.

  • Frequent e-mail communication with the Oldtown CAG.
  • On January 9, 2001, BEHS participated in an IDEQ sponsored community meeting.
  • On February 23, 2001, BEHS convened a public meeting.
  • On June 27, 2001, BEHS participated in an EPA sponsored community meeting.
  • On August 16, 2001, BEHS sponsored a conference called with CAG.
  • On August 23, 2001, BEHS investigator visited the Idaho Hill Elementary during EPASTART sampling activity.
  • On February 25, 2002, BEHS participated in an EPA sponsored community meeting. Apublic availability session was held after the meeting. BEHS distributed a healthconcerns survey. Community members have the options of filling out the survey ortalking to ATSDR, CDRI, or BEHS staff in a confidential private setting. A copy of thesurvey is attached in Appendix M.
  • In March 2002, BESH sent the above survey to all residents in the Oldtown ZIP Code(83822) area.
  • On May 9, 2002, BEHS participated in an EPA sponsored community meeting. BEHSpresented the preliminary results of the health concerns survey distributed on February25 and mailed in March 2002. The result of the survey is attached in Appendix N.
  • On July 18, 2002, BEHS provided the community an opportunity to comment on thedraft public health assessment. Prior to that the Oldtown Community Advisory Groupwas given the opportunity to comment on the document. Advisory Group comments, intheir entirety, were included in the public comment version of the public healthassessment as an addendum for the public to view. No comments were received fromthe general public . Comments from the Oldtown Community Advisory Group havebeen incorporated into the final document and addressed. BEHS response to commentscan be found in Appendix O.

Based on the responses from the written survey, e-mail communication, and the availabilitysession, the following sections list the three common types of questions/issues raised.

5.3.1 Environmental Related Questions

After reviewing the START IA final report, the community raised many questions regarding thelaboratory and field sampling techniques, as well as the future plans of EPA. Questions relatedto environmental issues are listed below. Some replies are excerpted from e-mailcommunication between the EPA START site manager and the communities.

  1. What are blanks? What is a surrogate compound? What type of data was rejected? Does that influence the data quality?

Reply: There are many different types of blanks. For example, the additional samples submittedby the field crews include trip blanks, field blanks, and rinseate blanks. Those blanks insurecontamination did not occur while handling and transporting samples. There are also laboratoryblanks which are generated to insure there are no contamination in the water and chemicals thatlaboratory uses to analyze the samples. Blanks are part of the quality assurance (QA) to makesure that the field and laboratory processes are not contributing contamination to the results. Surrogate compounds are chemicals that are added at a known concentration to the sample. Thelaboratory tests for theses surrogate compounds along with the other analytes per the analyticalmethod. If the recovery of the surrogate compound (detected amount) is low or falls outside theexpected range, the sample result does not meet the quality control (QC). That means if theinstrument was not able to detect the surrogate and report the known concentration, it probablycould not detect the analytes of question. As part of EPA's QC process, a result can be rejecteddue to low recoveries of the surrogate compound. It is unfortunate that rejection happens. Forthe Poles, Inc. samples, particularly for the contaminants of concern, PAHs and penta, EPA hasthe confidence about the data quality after the QA/QC process.

  1. What are "Preliminary Remediation Goals?"

Reply: Preliminary Remediation Goals (PRGs) are tools for evaluating and cleaning upcontaminated sites. They are risk-based concentrations derived from standardized equations. They are generic and are calculated without site-specific information. The PRGs used are fromEPA Region IX. They are agency guidelines and are not legally enforceable standards. They aretypically used for site "screening" and as initial cleanup goals.

  1. The Idaho Ambient Air Criteria (IAAC) for penta is 25 g/M3. Is this similar to the AmbientAir Criteria in other states? Why is there such a large discrepancy between IAAC and theEPA Region IX PRG of 0.056 g/M3?

Reply: IAAC for penta was established in reference to an occupational standard. A protectivefactor for public, since general population is more sensitive than healthy workers are, is applied. When the standard was set for Idaho, the carcinogenicity of penta was not considered. IDEQ isnow considering revising the IAAC for penta to err on the side of protection. Fifteen statescurrently have penta ambient air standards ranging from 1.19 to 30 g/M3. The Idaho criterion iscomparable to most states. It is important to note, the IAAC for penta is an incremental increasecriteria and is only applicable to a new facility or existing facility that requests operationalchanges. The EPA residential air PRG is a theoretical calculation assuming a relatively highdaily air inhalation rate over a lifetime. Obviously, this scenario is unlikely. The PRG tends tobe overly conservative and therefore a great tool for site "screening".

  1. EPA proposed to conduct air sampling during "the worst case scenario." According to the START IA report, the air samples were collected when there was "light to moderate odor." That was not representative of the worst case. Will EPA conduct additional sampling for the "actual" worst case that is verified and concurred by the communities?

Reply: No, EPA currently does not plan to conduct additional air sampling for the followingreasons. First, Poles, Inc. has installed a vapor condensing system prior to EPA's samplingactivities. The air emission is better controlled compared to the past. The odor coming from thetreatment process has greatly decreased according to nearby residents. It may not be possible toregenerate the past "worst case scenario." Second, it is very difficult and extremely costly toschedule a sampling event around odor and metrological conditions. EPA did conduct airsampling during the butt-dipping process which is believed to represent "the worst case" underthe current operating system. Third, air sampling results were evaluated together with dust wipeand off site surface soil samples to determine if deposition of particulates has occurred. Lastly,BEHS uses the maximum detected air concentration to estimate people's exposure through theair pathway. The worst case exposure condition should be well captured by the public healthassessment process.

  1. Dioxin is one of the impurities in penta. Is Dioxin present or has it been tested for?

Reply: Sampling for dioxin did not occur in the START IA. Except for the penta concentrationin outdoor air, EPA did not find any other site-related contaminants in offsite samples that wereabove PRGs. Since dioxin is less volatile than penta, it is less likely to be released into the air. Recently, EPA conducted additional soil dioxin and furan sampling both on and off the site. The chemicals were found, but sampling concentrations did not exceed ATSDR's health-basedcomparison values or meet criteria for further evaluation.

  1. Did EPA test the Pend Oreille River water? If not, why not?

Reply: EPA did not test the river water but did test the sediment in the River. A fewcontaminants were found at low concentrations in the sediment samples. Since penta stays insoil and sediment better than in water, EPA analyzed sediment as an initial screening tool.

  1. EPA is in the process of determining if Poles, Inc. meets the Hazard Ranking System (HRS)criteria for proposal to the National Priority List. How long will this process take?

Reply: The EPA START developed a preliminary score for HRS. It is currently undermanagement review. The final score might take another six months to finalize (expected August2002). As of September 2002, a HRS score was not announced by EPA.

  1. Arsenic was found in soils. Will EPA clean up arsenic?

Reply: No, EPA cannot clean up arsenic that exists naturally in the environment. However,BEHS has a fact sheet specifically addressing how to reduce personal exposure to backgroundarsenic. Please contact BEHS for more information.

  1. The EPA START in the IA found that certain areas of Poles, Inc. do not have propersecondary containment. Why did IDEQ not find violations in their previous investigation?

Reply: The EPA START team is trained to do Spill Prevention Control and CountermeasureInspections (SPCC) while inspectors from IDEQ are trained to observe hazardous wastedisposal. It is unfortunate that the problem was not caught early. Poles, Inc. is in violation ofthe SPCC regulation and EPA will address this compliance issue for the site.

  1. The wood bark/wood shaving used on the Idaho Hill Elementary School playground wasdonated by Poles, Inc. EPA has now found contamination onsite. Is it possible that the barkon the school playground is contaminated? Penta was detected at low levels in schoolplayground. Is there other possible source besides coming from the site?

Reply: Penta found on the school playground could be coming from trespassers tacking dirtfrom the site. It could also be the donated bark/shavings from the site. It may also be theinfluence of nearby penta treated utility poles. However, the level of penta found in schoolplayground was not at levels likely to result in adverse health effects. BEHS cannot identify aspecific source that contributed to the low level of penta found in the school playground.

5.3.2 Health-Related Questions

  1. Many people in the community have/had cancer. Are those cancers caused by exposures to the contamination from the site?

Reply: Cancer is not a single disease. Different types of cancer have different causes and riskfactors. Since cancer is, unfortunately, a common disease (one of every three of us will developcancer in our lifetime), every community will experience a certain number of cancers. Becausecancers generally take a long time to develop, identifying an exposure that occurred 10-20 yearsago is difficult. Even if a potential exposure is identified, epidemiologists and toxicologists maystill not know if a person's cancer is a direct result of a specific chemical without knowing otherrisk behaviors and family history of the individuals. BEHS and CAWG are currentlyinvestigating cancer types that are biologically plausible as a result of penta and backgroundarsenic exposures. An elevated rate of sarcoma was observed in the Oldtown, Priest River, IDand Newport, WA area. CAWG currently does not know the cause of the sarcoma cluster.

  1. The School used to have asbestos in the building. Can any of the cancers be related to asbestos exposure?

Reply: Asbestos causes lung cancer as well as one distinct type of disease, called asbestosis.BEHS is not aware any cases of asbestosis in this area for the past decade. The cancers wereunlikely to be related to asbestos in the school building.

  1. The chemical smell that used to come from the facility was irritating. Was the smell a health concern? What are agencies planning to do to deal with it?

Reply: There were contaminants detected in both indoor and outdoor air. BEHS and ATSDRdetermined that exposure to chemicals through the air pathway is unlikely to cause imminentadverse health effects in the general population. There is also no apparent increased risk ofgetting cancer form long-term exposure. However, annoying odor can cause short-term physicalor psychological effects including difficultly concentrating, headache, fatigue, depression,irritability, nausea, dizziness, and nasal stuffiness. IDEQ planned to request an odormanagement plan and a fugitive dust control plan from Poles, Inc.; however, the site is no longertreating poles and the odor issue has been eliminated.

  1. ATSDR stated in its Memorandum to EPA that "There are no known health guidelines forinhalation exposure to penta." If that is the case, then how can ATSDR determine that thereare not imminent health risks and increased cancer risks? On what are they basing thatdetermination?

Reply: Standards or guidelines from oral studies are used to assess inhalation exposure wheninhalation data are not available.

  1. Cedar bark was placed under all the school playground equipment. Allergic reactions tocedar are similar to what students and teachers report. Is it possible that those symptomsare caused by allergic reactions to cedar rather than the chemicals?

Reply: It may be possible for a few cedar-sensitive individuals to express these symptoms. However, most people only experience symptoms while Poles, Inc. is operating. For themajority, their symptoms are more likely to be the result of odor irritation rather than the cedarbark.

  1. Dioxin is one of the impurities in penta. Can I get my body fat tested for dioxin? If so, where can I get it done and who is paying for it?

Reply: Testing dioxin in body fat is a costly and invasive procedure. Body fat dioxin tests canonly prove that a person has been exposed to dioxin, not the source of dioxin. The test resultscannot predict whether or not adverse health effects would occur or how severe any effects mightbe. EPA is currently planning to conduct soil dioxin testing for the site. Before dioxin data isavailable, BEHS does not recommend body fat dioxin testing for the general population sinceexposure to other site-related contaminants does not pose a public health hazard

  1. EPA found groundwater contamination. There are eight wells that occasionally serve as the public drinking water source. Is it safe to drink public water?

Reply: All eight wells are located up gradient of the facility. Contamination is unlikely toimpact the up gradient wells. IDEQ tested one of the municipal wells and did not detect pentaand PAHs in the water. Public water systems routinely test for water quality and they have to beunder compliance with regulatory standards. It is safe to use public water.

  1. Should I be concerned about my children's health while attending Idaho Hill Elementary?

Reply: Penta was not detected in air samples collected inside of school. Classroom dustsamples and surface soils from the school playground had none or low levels of contamination. There is one exposure possibility to which children could be more susceptible than adults. Children exposed to onsite soil from trespassing though the facility or playing around the polestorage area may be a concern. BEHS advises children not to trespass through or play at the site.

  1. Is penta more harmful to immune system-compromised individuals?

Reply: Some epidemiological studies and case reports show that exposures to technical gradepenta cause certain immunological effects. Immune system-compromised individuals may bemore sensitive to penta than healthy adults. BEHS advises those individuals to avoid trespassingthrough the site and to consult an occupational physician, if they are experiencing symptoms.

  1. The Occupational Safety and Health Administration (OSHA), a federal agency, hasdeveloped a Permissible Exposure Limit (PEL) for penta, 0.5 mg/M3. This level issignificantly lower than the PELs for cyanide (5 mg/M3) and hydrogen cyanide (11 mg/M3). Hydrogen cyanide has been used as gas chamber poison gas. Does that mean penta is 10 ormore times more toxic than the well-known toxic gas?

Reply: The PEL developed by OSHA is the averaged concentration over an 8-hour workday and40-hour work week that workers can be exposed to for a long period of time (assuming 25 yearemployment) without causing adverse health effects. Short-term exposure to high levels ofcyanide or hydrogen cyanide can be deadly (approximately 100--500 mg/M3 depending onexposure duration). However, most of the cyanide or hydrogen cyanide at low levels leaves thehuman body within 24 hours (i.e., worker's body eliminates cyanide during off duty hours). Since cyanide and hydrogen cyanide are not classified as carcinogens, the long-term cancerouseffect was not a factor while developing PELs. Penta is a probable human carcinogen, theallowable exposure over a long period of time for penta is expected to be lower. Lower PELdoes not mean the acute toxicity of penta is 10 times higher than hydrogen cyanide since thePEL is developed for a long-term exposure duration.

5.3.3 Other Questions

  1. Why do agencies not address the possibility of banning penta?

Reply: Banning penta is not the scope of the health agencies at the Oldtown site. The EPApesticide branch reevaluates all pesticides that were registered before November 1984, of whichpenta is one. When EPA completes the review and risk management decision for a pesticide thatis subject to reregistration, a Reregistration Eligibility Decision (RED) document is issued. TheRED summarizes the risk assessment conclusions and outlines any risk reduction measuresnecessary for the pesticide to continue to be registered in the U.S. For individuals who wouldlike to follow the establishment of a RED for penta, please contact EPA's pesticide branch formore detailed information.

  1. Poles, Inc. claimed that waste sludge in its dip tank has never been removed. How is thatpossible? An older gentleman said he used to shovel sludge out of the tank. EPA stated inthe IA that they removed seven 55-gallon drums of sludge. Is it possible that sludge wasdumped illegally?

Reply: Poles, Inc. has installed lids on its dip tank in the recent years. Before the lids wereinstalled, sludge was accumulated at a much faster rate. By keeping precipitation out of thetanks by using covers, much less sludge has been formed in recent years. Poles, Inc. distributedthe waste sludge to nearby farmers before penta was banned for personal and farming use. Itwas not known how much and how regularly this practice occurred. People who had receivedpenta sludge previously are encouraged to contact BEHS. According to the IA report, Poles, Inc.has not removed waste sludge from the dip tank since penta was banned for personal use. Thecapacity of the dip tank is approximately 68,000 gallons. The 385 gallons (seven 55-gallondrums) of sludge removed by EPA was approximately 1 inch deep at the bottom of the dip tank. The sludge did not accumulate to a point to interfere with treatment of the poles because thepoles were placed on steel racks in the tank that stood six inches above the bottom of the tank. IDEQ's hazardous waste disposal investigators did not find signs of illegal waste disposal over multiple site visits.


6. CONCLUSIONS

1. BEHS has evaluated the completed and potential exposure pathways related to the Poles, Inc.,Wood Treatment Facility. The following conclusions, based on ATSDR's Interim Public HealthHazard Categories (see Appendix K), provide a public health perspective to each of thesepathways:

  • Most recently, children, adults, and workers were likely to be exposed to penta,dioxin/furan, and PAH contaminated soils. However, these exposures are not likely toresult in adverse health effects; therefore, this exposure pathway is categorized as a noapparent public health hazard. Long-term exposure by workers and local residents whoregularly trespass does not increase the risk of developing cancer from exposure to onsitesurface soil.
  • EPA air sampling was conducted after Poles, Inc had taken measures to improve airemissions. Past exposures could have been higher but it is not possible to determine thepublic health implications of these exposures. Current exposures through the air pathwayare not expected to result in adverse health effects for the community around the site. Currently there is no apparent public health hazard from air exposures. Additionally, thesite has stopped treating poles.
  • The groundwater pathway cannot be fully established, therefore, it is characterized as anindeterminate public health hazard. According to EPA, most people in the communityuse public water as their drinking water source. The public water system in Oldtowndraws surface water from up stream of the facility. There are 46 private wells located upgradient and within a 1-mile radius of the site. It is not known if people use these privatewells or if the well water is from the same aquifer as the EPA monitoring wells wherecontamination was detected. Contaminants found in groundwater may only pose a risk tothe public if exposure occurs.
  • Exposures to contaminants measured in the off site surface soil and the Pend OreilleRiver sediment are unlikely to result in adverse health effects for the residents,recreational sportsmen, or children playing along the river or their own backyard. Theseexposure pathways are considered no apparent public health hazards.
  • Currently there is no exposure through onsite subsurface soil because the general publicis unlikely to have contact with subsurface soil. There is also no exposure throughinhaling or touching indoor dust because no site-related contaminants were detected. Exposure to onsite subsurface soil and indoor dust are categorized as no public healthhazard.
  • Water and fish (or other biota) from the Pend Oreille River were not sampled. However,exposures to contaminants through these two exposure pathways are not likely at levelsof public health concern; therefore, they are categorized as no apparent public healthhazards.

2. The odor issue appears to have been resolved for teachers and children at Idaho HillElementary once Poles, Inc. started treating poles at night. Prior to the site ending pole treating,the smell was further reduced and became less noticeable, according to the nearby residents,since the vapor condensing system was installed.

3. Background arsenic was found in soil, sediment, and groundwater. The exposure dosescalculated were lower than the lowest CELs for arsenic. BEHS does not expect an increased riskof developing cancer from long-term exposure to regional levels of background arsenic.

4. For the period between 1992 and 1999, the rates of 24 out of 26 cancer types in the Oldtown,Priest River and Newport area were within or lower than their expected ranges at the 95%confidence level. The two types of cancer with significantly elevated rates were sarcoma andfemale lung and bronchus cancer. Behavioral factors are the primary risk factors for lung andbronchus cancer. The elevated cancer rate of female lung and bronchus cancer is not likely to becaused by site-related exposures. On the other hand, sarcoma is a rare cancer. Soft tissuesarcoma might be associated with penta exposure. Some risk factors for sarcoma includeprevious radiation therapy, exposure to chemicals (e.g., vinyl chloride, agent orange),immunodeficiency, chronic tissue irritation, and/or genetic influence. The association betweensite-related exposure and the sarcoma cases is currently unknown and is under investigation.

5. Community concerns included the following general categories: data quality from theSTART IA, exposure to site contaminants (particularly in school), future testing and otheractivities, cancer rates in school teachers and the broader community, impurities such as dioxin, and odor control.


7. RECOMMENDATIONS

1. As a precaution and as prudent public health practice because there is contamination andphysical hazards onsite, site access should be restricted by placing obvious signs or barriers atthe site boundaries to prevent the public from entering. BEHS should inform the public aboutthe chemical and physical hazards of trespassing and playing at the Poles, Inc. property. Workers should be cautious about tracking dirt back home and mixing work clothes with theirfamily's clothing.

2. A well survey (beneficial use survey) should be conducted to determine if groundwater hasbeen used as drinking water, irrigation, or for any other purpose near the site. Additional downgradient monitoring wells should be installed and monitored frequently. Private wells near thesite that are used as a drinking water source should be tested for contamination. BEHS andATSDR should evaluate the public health implications of any exposures determined from thesampling and survey.

3. The seven sarcoma cases should be further investigated in order to determine the associationwith the Oldtown site. The relationship of the soft tissue sarcoma cases with Poles, Inc. facilityneeds to be clarified (i.e., work at the facility or live near the facility). The family history,occupation, and personal experiences that involved additional risk factors associated with softtissue sarcoma should be noted.

4. Cancer incidence evaluation targeting current and past school employees should be further investigated.


8. PUBLIC HEALTH ACTION PLAN

The purpose of the public health action plan is to ensure this public health assessment not onlyidentifies any current and potential exposure pathways and related health hazards, but also toprovide a plan of action to mitigate and prevent adverse human health effects resulting fromexposures to hazardous substances in the environment, even if those exposures are not expectedto make people ill. The first section of the public health action plan summarizes completed andongoing actions at the site. The second section lists additional public health actions that are planned for the future.


8.1 Completed Actions

1. In response to odor complaints, IDEQ has visited Poles, Inc. multiple times to investigatehazardous waste generation, management and disposal practices. Air modeling was conductedto predict possible off site exposures to penta. BEHS reviewed IDEQ's air modeling results andrecommended a thorough investigation be conducted for the site. Additionally, IDEQ sampledsurface soil at Poles, Inc. and found elevated levels of penta and PAHs.

2. In response to a citizen's petition and the request from IDEQ and BEHS, the EPA STARTconducted an IA for the Poles, Inc. site. IDEQ and BEHS were involved in reviewing the IAsampling plan. The IA report was finalized in January 2002 and demonstrated that Poles, Inc.had violations under SPCC and the Resource Conservation and Recovery Act (RCRA).

3. BEHS and CDRI conducted cancer incidence evaluations for the area (Oldtown, Priest River,and Newport) and found an elevated rate of sarcoma cancer.

4. BEHS under its cooperative agreement with ATSDR prepared three health consultations priorto this public health assessment. The first health consultation evaluated IDEQ's air modelingresults and the second and third health consultations were technical assistance consults thatdocuments BEHS's suggestions to START IA sampling plan and BEHS's responses to thecommunity questions/issues.

5. BEHS developed and distributed six health education fact sheets to the community. Three ofthem were chemical informational fact sheets for penta, PAHs, and arsenic. One fact sheetsummarized BEHS health consultations. The final two were fact sheets providing updates onsite and BEHS's activities to the community members. BEHS also facilitated the activities ofthe CAG.

6. EPA conducted limited soil sampling for dioxins and furans at the site, at a nearby residenceand at Idaho Hill Elementary school.

7. The site owner signed a consent order with IDEQ.

8.2 Ongoing or Planned Actions

1. The EPA START is in the process of determining the HRS score for Poles, Inc.

2. EPA and IDEQ are negotiating with the site owner how to prevent public exposure to theonsite surface soil. Possible actions include site access restriction or installing an asphalt cap. IDEQ and EPA are evaluating the logistics for a soil removal action.

3. IDEQ will request a Tier II operating permit application, emission characterization, fugitivedust control plan, and odor management plan from Poles, Inc. in order to better characterize andcontrol future air emissions and odors.

4. EPA and IDEQ will require Poles, Inc. to perform further investigation of contamination,perform necessary corrective action to mitigate or eliminate potential exposure, and installadditional point of compliance, down gradient monitoring well(s) and monitor the well quarterly. A beneficial use survey will be performed to better understand the groundwater usage for thearea. BEHS and ATSDR will evaluate the public health implications of any exposuresdetermined from the sampling and survey.

5. EPA and IDEQ will discuss possible plans with the site owner to control current and futurecontamination of surface and subsurface soil. Remedial action and installation of an asphalt capare currently being considered. EPA will request a valid SPCC Plan to prevent futurecontamination. The plan may include an impervious surface, adequate secondary containment,and employee training.

6. CAWG will further investigate the biologically plausible cancer cases from penta for theOldtown area. A case survey (i.e., questionnaire) inquiring about the medial, family, andpersonal history of the cases will be administered by CDRI to gather key information on possibleexposures to site-related chemicals. CAWG will continue to try to collect information aboutcancer among the Idaho Hill Elementary school employees.

7. BEHS will provide health education to the community to assist residents in mitigating exposure to the area background soil arsenic.


9. REFERENCES

ATSDR 1992. Toxicological Profile for Vanadium. US Department of Health and HumanServices, Public Health Services, Agency for Toxic Substances and Disease Registry.Atlanta, GA.

ATSDR 1994. Toxicological Profile for Chlorodibenzofurans. US Department of Health andHuman Services, Public Health Services, Agency for Toxic Substances and Disease Registry.Atlanta, GA.

ATSDR 1995. Toxicological Profile for Polycyclic Aromatic Hydrocarbons (PAHs) (update). US Department of Health and Human Services, Public Health Services, Agency for ToxicSubstances and Disease Registry. Atlanta, GA.

ATSDR 1998. Toxicological Profile for Chlorinated Dibenzo-p-dioxins. US Department ofHealth and Human Services, Public Health Services, Agency for Toxic Substances andDisease Registry. Atlanta, GA.

ATSDR 2000a. Toxicological Profile for Pentachlorophenol (update). US Department of Healthand Human Services, Public Health Service, Agency for Toxic Substances and DiseaseRegistry, Atlanta, GA.

ATSDR 2000b. Toxicological Profile for Arsenic (update). US Department of Health andHuman Services, Public Health Service, Agency for Toxic Substances and Disease Registry,Atlanta, GA.

ATSDR 2001. STRIKE Team Request Memorandum Concerning Ambient Air Data at Poles,Inc., November 20, Atlanta, GA.

BEHS 2001a. Health Consultation -- Evaluation of Potential Pentachlorophenol AirContamination Based on the Idaho Department of Environmental Quality April 2001 AirModeling Results. Poles, Inc. Wood Treating Facility, Oldtown, Bonner County, ID. Bureau of Environmental Health and Safety, Division of Health, Idaho Department of Healthand Welfare. Boise, ID.

BEHS 2001b. Health Consultation - Evaluation of EPA's Integrated Assessment Sampling andQuality Assurance Plan. Poles, Inc. Wood Treating Facility, Oldtown, Bonner County, ID. Bureau of Environmental Health and Safety, Division of Health, Idaho Department of Healthand Welfare. Boise, ID.

BEHS 2002. Health Consultation - Technical Assistance to Oldtown Community AdvisoryGroup, Poles, Inc. Wood Treating Facility, Oldtown, Bonner County, ID. Bureau ofEnvironmental Health and Safety, Division of Health, Idaho Department of Health andWelfare. Boise, ID.

BVRHS 2001. Idaho Behavioral Risk Factors. Bureau of Vital Records and Health Statistics,Division of Health, Idaho Department of Health and Welfare. Boise, ID.

Census Bureau 2000, Census 2000 Summary File. Bonner County, Idaho and Pend OreilleCounty, Washington. http://www.census.gov/Press-Release/www/2001/sumfile1.html

EPA 1993. RCRA Compliance Inspection Report, EPA ID009061714. US EnvironmentalProtection Agency, Seattle, WA.

EPA 1997. Exposure Factors Handbook, Volume I, General Factors. EPA/600/P-95/002Fa.Office of Research and Development, US Environmental Protection Agency, Washington,DC.

EPA 2002a. Poles Incorporated Site Integrated Assessment Report. Oldtown, Idaho. TDD:01-07-0007. Contract: 68-S0-01-01. Superfund Technical Assessment and Response Team Two,US Environmental Protection Agency, Seattle, WA.

EPA 2002b. Poles Incorporated Dioxin/Furan Sampling Trip Report. Oldtown, Idaho. TDD:02-05-0014. Contract: 68-S0-01-01. Superfund Technical Assessment and Response Team, USEnvironmental Protection Agency, Seattle, WA.

IDEQ 2000. Oldtown Air Quality Inspection Report, Airs No. 017-00039. Idaho Department ofEnvironmental 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.

IDEQ 2001. Poles, Inc. Surface Soil Sampling Results, Idaho Department of EnvironmentalQuality. Coeur d'Alene, ID.

IRIS 1987. Integrated Risk Information System Substance File - Pentachlorophenol (CASRN87-86-5), http://www.epa.gov/iris/subst/0086.htm. US Environmental Protection Agency,Washington, DC.

IRIS 1994a. Integrated Risk Information System Substance File - Benz(a)anthracene (CASRN56-55-3), http://www.epa.gov/iris/subst/0454.htm. US Environmental Protection Agency,Washington, DC.

IRIS 1994b. Integrated Risk Information System Substance File - Benzo(b)fluoranthene(CASRN 205-99-2), http://www.epa.gov/iris/subst/0453.htm. US Environmental ProtectionAgency, Washington, DC.

IRIS 1994c. Integrated Risk Information System Substance File - Benzo(a)pyrene (CASRN 50-32-8), http://www.epa.gov/iris/subst/0136.htm . US Environmental Protection Agency,Washington, DC.

IRIS 1994d. Integrated Risk Information System Substance File - Dibenzo(a,h)anthracene(CASRN 53-70-3) http://www.epa.gov/iris/subst/0456.htm. US Environmental ProtectionAgency, Washington, DC.

IRIS 1994f. Integrated Risk Information System Substance File - Ideno(123,-cd)pyrene(CASRN 193-39-5), http://www.epa.gov/iris/subst/0457.htm. US Environmental ProtectionAgency, Washington, DC.

IRIS 1996. Integrated Risk Information System Substance File - Vanadium Pentoxide (CASRN1314-62-1), http://www.epa.gov/iris/subst/0125.htm. US Environmental Protection Agency,Washington, DC.

IRIS 1998. Integrated Risk Information System Substance File - Inorganic Arsenic (CASRN7440-38-2), http://www.epa.gov/iris/subst/0278.htm. US Environmental Protection Agency,Washington, DC.

NRC 1989. Recommended Dietary Allowances. 10th edition, National Research Council,National Academy Press, Washington, DC.

Johnson, C.J. 2001. Epidemiologist Cancer Data Registry of Idaho, Personal communicationwith Mingyi Trimble, Toxicologist, Bureau of Environmental Health and Safety, Division ofHealth, Idaho Department of Health and Welfare, Boise, ID.

Lyon, P. 2002. Hazardous Waste Manager Idaho Department of Environmental Quality, Personalcommunication with Mingyi Trimble, Toxicologist, Bureau of Environmental Health andSafety, Division of Health, Idaho Department of Health and Welfare, Boise, ID.

NRC 1989. Recommended Dietary Allowances. National Research Council, 10th edition,National Academy Press, Washington, DC.

Tylor, R. 2002. Water Analyst, Idaho Department of Environmental Quality, E-mailcommunication with Aaron Scheff, Health Educator, Bureau of Environmental Health andSafety, Division of Health, Idaho Department of Health and Welfare, Boise, ID.

Woodke, M. 2002. Project Manager, Ecology and Environment, Inc., E-mail communicationwith Mingyi Trimble, Toxicologist, Bureau of Environmental Health and Safety, Division ofHealth, Idaho Department of Health and Welfare, Boise, ID.


10. PREPARERS OF REPORT

Report Authors

Primary: Mingyi W. Trimble, Sc.D., Health Assessor/Toxicologist
Secondary: Elke D. Shaw-Tulloch, M.H.S., Program Manager/ Bureau Chief


Reviewers

Elke D. Shaw-Tulloch, M.H.S., Program Manager/ Bureau Chief
Aaron M. Scheff, M.Ed., Health Educator

Environmental Health Education and Assessment Program
Bureau of Environmental Health and Safety
Division of Health
Idaho Department of Health and Welfare
450 W. State Street, 4th floor
P.O. Box 83720
Boise, Idaho 83720-0036


ATSDR Technical Project Officer

Gregory V. Ulirsch, M.S., Environmental Health Engineer

Division of Health Assessment and Consultation
Superfund Site Assessment Branch
Agency for Toxic Substances and Disease Registry
1600 Clifton Avenue, Mailstop E-32
Atlanta, Georgia 30333


ATSDR Regional Representatives

Karen L. Larson, Ph.D., Regional Representative

Office of Regional Operations, Region X
Agency for Toxic Substances and Disease Registry
1200 Sixth Avenue, Room 1930 (ATS-197)
Seattle, WA 98101


11. CERTIFICATION

The Idaho Bureau of Environmental Health and Safety prepared this Public Health Assessmentunder 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 Public Health Assessment was initiated.

Gregory V. Ulirsch
Technical Project Officer, SSAB, DHAC


The Superfund Site Assessment Branch (SSAB), Division of Health Assessment andConsultation (DHAC), ATSDR has reviewed this health consultation and concurs with itsfindings.

Alan W. Yarbrough
for Roberta Erlwein
Chief, SPS, SSAB, DHAC, ATSDR



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