PUBLIC HEALTH ASSESSMENT
AT & SF (ALBUQUERQUE)
ALBUQUERQUE, BERNALILLO COUNTY, NEW MEXICO
In conducting an ATSDR public health assessment, the health assessors identify and review allavailable environmental contamination data from a site. This Environmental Contamination andOther Hazards section describes the sampling that has been done and identifies contaminants ofconcern. Data used in this public health assessment is taken primarily from the EPA HazardRanking System (HRS) Documentation Record (1) and the Site Investigation Report (2). TheHRS Documentation Record includes on-site data from the Phase I - IV investigations conductedby Radian Corporation between 1988 and 1990. Radian is a consultant to the Atchison, Topeka& Santa Fe Railway Company.
The quality of the environmental data is discussed in the Quality Assurance and Quality Controlsubsection. Physical and other hazards not related to toxic substances, if any, are described inthe Physical and Other Hazards subsection. This introductory portion discusses the process forselecting contaminants of concern and Toxic Chemical Release Inventory (TRI) data.
Selection of Contaminants of Concern
ATSDR selects contaminants for further evaluation based upon the following factors:
- comparison of concentrations of contaminants on- and off-site with values for non-carcinogenicand carcinogenic endpoints,
- sampling plan and field and laboratory data quality, and
- community health concerns.
Identification of a contaminant of concern in the On-Site and Off-Site Contamination subsectionsdoes not mean that exposure to those substances will result in adverse health effects, only thatadditional evaluation is necessary. The likelihood of exposure to the contaminant and the publichealth significance, if any, is evaluated in subsequent sections of the public health assessment.
Comparison values are contaminant concentrations in specific media that are used to selectcontaminants for further evaluation in the public health assessment. In this public healthassessment, RMEGs, CREGs and LTHAs are used as comparison values. Reference Dose MediaEvaluation Guides (RMEGs) are concentrations based on EPA's estimates of the daily exposureto a contaminant that is unlikely to cause adverse non-cancer health effects. Cancer EvaluationGuides (CREGs) are estimated comparison concentrations, for specific chemicals, based on anexcess cancer rate of one in a million persons and are calculated using EPA's cancer slopefactors. Lifetime Health Advisories (LTHAs) are drinking water concentrations at which, after alifetime exposure, adverse noncarcinogenic health effects would not be expected; the EPAdetermines LTHA levels.
Review of Toxic Chemical Release Inventory (TRI) Data
The EPA Toxic Chemical Release Inventory (TRI) was searched for information on toxicsubstances used by industries in the vicinity of the site (i.e., in the 87102 and 87105 zip codes)during the years 1987 through 1992 (the only years for which information is available). Thatsearch did not disclose information about the AT&SF site. Chemical releases to the atmospherefor several industrial plants in the site vicinity were reported. With the exception of xylenes andnaphthalene, the chemicals that were reported as released were not found on the site. One plantreported releasing xylene to the atmosphere and another reported releasing naphthalene to theatmosphere; the database does not provide sufficient information to estimate airborneconcentrations either at the plant or downwind. For this reason, and because xylenes andnaphthalene have not been reported at levels of public health concern for any media at the site,chemical releases reported in the TRI will not be further considered in this assessment.
During the period the tie treatment plant was in operation, waste-waters containing creosote inoil, naphtha and other chemicals were reportedly diverted into 1.2 acres of unlined earthenholding ponds. According to the 1988 and 1990 investigations conducted by RadianCorporation, the two sources of on-site contamination are a waste-water impoundment and awaste-water impoundment sump. Soil, sludge and groundwater from the source areas weresampled. Quantitative data available to ATSDR at the time this document was written includessampling information on soil and groundwater. Contaminants detected in groundwater were alsoidentified in soil borings and sludge samples. Constituents detected at the site were typical of thecreosoting processes of wood treatment operations.
During the Phase IV investigation (1990) subsurface soil samples were taken from the top andbottom of the clay layer which separates the shallow and intermediate aquifers. Creosotecontamination was detected within two of six on-site clay layer borings. One sample from theupper portion of the clay (depth 19-21 ft. below ground level) showed low levels ofdibenzofuran, fluorene, naphthalene and phenanthrene. The other sample, from the lowerportion, contained low concentrations of acenaphthene, dibenzofuran, fluorene and moderateconcentrations of 2,4 dimethylphenol and naphthalene (Refer to Table 1 for concentrationlevels). The remaining boreholes showed no detectable levels of organics except for trace levelsof toluene (also detected in groundwater during Phase III investigation). The presence ofmethylene chloride, evident in all samples, was attributed to laboratory contamination.
The contamination plume in the soil appears to be centered on the waste-water reservoir. Sincethe soil samples collected were likely to be partly saturated, the level of creosote in the soilsample may also include creosote that was dissolved in the groundwater. Thus reportedconcentrations of creosote in soil samples may be slightly elevated due to the concentrationattributed to the saturated portion of soil.
Tables 1-3 list the concentration ranges detected in contaminants contained in soil andgroundwater along with the comparison value for the contaminant (if one has been established). If the maximum contaminant concentration detected exceeds the comparison value, it does notnecessarily mean that the contaminant will cause health effects from exposures. Instead, itidentifies which contaminants require further evaluation in the public health assessment.
The data tables include the following abbreviations:
- RMEG = Reference Dose Media Evaluation Guide
- LTHA = Lifetime Health Advisory for drinking water (EPA)
- ug/l = microgram per liter
- ug/kg = microgram per kilogram
- CREG = Cancer Risk Evaluation Guide for 1x10-6 excess cancer risk
|CONTAMINANT||Concentration Range |
Phase IV, Subsurface (12a & 12bborings)
Phase III, Unspecifieddepth and location
|COMPARISON VALUE (CV)FOR INGESTION|
|acenapthene||200 -1200||ND-32000 (68000J)||100,000||RMEG (pica)|
|fluoranthrene||ND-330||ND-40000 (55000J)||80,000||RMEG (pica)|
|fluorene||160-340||ND-40000 (69000J)||80,000||RMEG (pica)|
|pyrene||NA||ND-22000 (43000J)||60,000||RMEG (pica)|
|*: Duplicate, J: Estimated concentration, Material present quality control criteria unreliable, ND: not detected, NA: not analyzed|
Hazard Ranking Document (Phase IV Site Investigation Report for the AT&SF, Albuquerque, New Mexico, October 1990
All hazardous substances found in soil were also detected in sludge samples during the1988 investigation. In addition to those constituents, the following were identified in sludgesamples (1): lead, ethylbenzene, toluene, pyrene, xylene, dibenzofuran.
Groundwater is reported to flow beneath the site in an easterly direction east of the RioGrande (1). Nested monitoring wells drilled into the shallow and intermediate aquiferswere placed upgradient of and within the center of the area believed to be the source ofcontamination.
In February 1990 Radian collected background groundwater samples from two well pairs(MW9a, MW9b, MW13a and MW13b). Analysis of the samples indicated the presence ofthe following analytes at levels barely exceeding the detection limits (1): acetone, methylenechloride, total xylenes, 1,1,1 trichloroethane, and bis(2-ethylhexyl)phthalate. Becauseacetone, methylene chloride and bis (2 ethylhexyl) phthalate are common sampling and/orlaboratory artifacts, it is reasonable to assume their presence in the samples was not relatedto on-site contamination.
|CONTAMINANT||Phase IVApril 1990||Phase IIIMay, June1988||Phase II June 1987||Phase IJanuary 1987||COMPARISON VALUE (CV) FORINGESTION|
|Concentration Range, ug/l||ConcentrationRange, ug/l||Concentration Range, ug/l||ConcentrationRange, ug/l||ug/l||Source|
|Hazard Ranking Document (Phase IV Site Investigation Report for the AT&SF, Albuquerque, New Mexico, October 1990). ND: notdetected NA: not analyzed|
Investigations have identified the location of the shallow alluvial aquifer contaminationplume in the center of the waste-water reservoir, extending radially outward with minorlobes to the south of the site. Some shift toward the east is evident in the intermediatealluvial aquifer. Monitoring wells MW10a, MW12b, MW12a, located within the plume,were used to evaluate an observed release to ground water.
Groundwater monitoring during the Phase IV investigation indicated off-site groundwatercontamination is primarily limited to the area south of the site with some migration towardthe west. Those wells closest in proximity to the waste-water reservoir such as 12a and 12bare affected and indicate the greatest concentration of volatile and semi-volatile organicconstituents. Chrysene was detected on-site during both the Phase II and III investigations. And, both 2,4 dimethylphenol and naphthalene were detected at levels exceeding ATSDRcomparison values (Refer to Table two for concentration levels). Monitoring wells west ofthe site contain only a few constituents with trace concentrations of volatile andsemi-volatile organics, toluene, xylenes, acetone, methylene chloride and bis (2 ethylhexyl)phthalate. As previously stated acetone, methylene chloride and bis (2 ethylhexyl)phthalate are common sampling and/or laboratory artifacts and thus may not originatefrom the waste-water reservoir.
There is no available on-site surface water data.
ATSDR is not aware of any off-site soil sampling.
The only source of off-site groundwater that ATSDR is aware of is private water wells.
In October 1992, a door-to-door survey of private water wells in the San Jose communitywas conducted. This survey was conducted in cooperation with the following groups: SanJose Community Awareness Council (SJCAC), San Jose Superfund Project-TAG, and theNew Mexico Environment Division. A total of fourteen wells were identified in an areabounded by San Jose Avenue on the north, Arno Street on the east, Stock Drive on thesouth, and 2nd Street on the west. Groundwater samples were collected from each well andwere analyzed for contaminants. ATSDR has been informed by a member of the studyteam that there are possibly 50 additional wells in the area. However, during the survey,the team members were not able to verify their existence. Follow-up interviews will beconducted by the SJCAC with occupants or owners of those lots who were not availableduring the door-to-door canvass (8).
The well survey study area was selected due to its proximity to the South Valley Superfundsite. Eight of the fourteen wells sampled were located in the southern-most area of SanJose, closest to the AT&SF site. Of the wells sampled during the survey these wells wouldbe considered most likely affected by the contamination plume beneath the AT&SF site dueto their proximity to the site. The remaining six wells were located in portions of the SouthValley community that overlie known but not fully defined ground-water plumes withinthe South Valley Superfund area.
Of all of the wells sampled, four of the fourteen had measurable levels of contaminants. Three of the wells were located within the South Valley Superfund area. Only one of thesethree wells is used for household purposes, and those purposes are other than consumption(washing, for example). It is not known whether the fourth well, which is located closer tothe AT&SF Superfund site, is used for consumption. In addition, ATSDR staff were notable to identify which one of these four wells contained the highest contaminant levels.
Furthermore, contaminants found in any of these wells may not be related to the AT&SFsite as only one constituent detected in the private well samples (xylenes) is alsodocumented as a contaminant in groundwater beneath the AT&SF site. Also, there areother sources of groundwater contamination in this area. Table 3 lists contaminants andtheir maximum concentrations found in private wells.
|CONTAMINANT||CONCENTRATION||COMPARISON VALUE (CV) FORINGESTION|
|j- the associated numerical value is an estimated quantity because quality control criteria were not met. However, presence of the material is reliable. |
Hazard Ranking Document (Phase I, II, IV Site Investigation Reports, AT&SF, Albuquerque, NewMexico. October 1988, 1990).
The EPA Hazard Ranking System Report states that NMEID sampling conducted in 1987indicates that creosote constituents may have migrated from the site to surface water. Noquantitative data was provided. Further documentation is required to establish thatsurface water is indeed contaminated (1).
In preparing this public health assessment, ATSDR relies on the information provided inthe referenced documents. We assume that adequate quality assurance and quality controlmeasures were followed regarding chain of custody, laboratory procedures, and datareporting. The analyses, conclusions, and recommendations in this public healthassessment are valid only if the referenced documents are complete and reliable.
There are no apparent physical or other hazards at this site.
In this section of the public health assessment, the possible exposure pathways areevaluated to help determine whether persons were, are, or will be exposed to contaminantsassociated with the site. Pathway analysis consists of five elements:
- identifying source of contaminant,
- determining the environmental medium and possible transport,
- identifying a point of exposure (i.e., a place or situation where humans might be exposedto the contaminated media),
- determining that there is a plausible route of human exposure (i.e., can the contaminantenter the body?), and
- identifying an exposed population (i.e., which individuals, if any, will come in contactwith the point of exposure).
An exposure pathway is considered complete when there is good evidence that all fiveelements exist. The presence of a completed pathway indicates that human exposure tocontaminants has occurred in the past, is occurring, or will likely occur in the future. When one or more of the five elements of an exposure pathway are missing, that pathway isconsidered potential. The presence of a potential exposure pathway indicates that humanexposure to contaminants could have occurred in the past, could be occurring, or couldoccur in the future. An exposure pathway can be eliminated if at least one of the fiveelements is missing and will never be present. Table 4 describes exposure pathways whichexist at this site.
There are no known completed pathways.
There is documented on-site groundwater contamination. Very limited off-site sampling ofgroundwater has been conducted by the State of New Mexico as part of a wellsurvey/monitoring project for the South Valley NPL site. This sampling, however,indicates that the potential for exposure to contaminated groundwater from off-site wellsexists. The relative contribution of the AT&SF site to the groundwater contamination mayor may not be determinable. Exposure to humans may occur if water drawn from privatewells is contaminated and is being used for drinking as well as other purposes.
The city of Albuquerque has indicated that municipal water may be at risk ofcontamination as a result of groundwater withdrawals which have created large area-widevertical hydraulic gradients that provide the driving force to transport shallowcontamination to lower depths. Contaminated groundwater at substantial depths has beendetected at the neighboring South Valley NPL site (10).
The U.S. Department of Interior, Fish and Wildlife Service has indicated that the site couldpresent substantial danger to wildlife resources exposed to materials present on site. Theyhave recommended to EPA that a biological inventory of the site be conducted to determinesite usage patterns by wildlife, and an ecological assessment be conducted that wouldinclude floral and faunal sampling to determine the extent of contamination and/orbioaccumulation in the food chain (11). Such an investigation may indicate that individualsparticipating in recreational activities such as fishing for consumption, may be at potentialrisk due to contamination which has bioaccumulated in the food chain.
Particulate release to air from contaminated soils is possible as there are no structures toprevent migration and the sump area contains no water. However, because the site is notclose to residences or work areas, significant exposure to contaminated particulates is notexpected. Possible contamination of neighboring agricultural fields, however, mayultimately contaminate animals if grazing is allowed. Such contamination may result incontaminated meat or dairy products consumed by people.
|PATHWAYNAME||EXPOSURE PATHWAY ELEMENTS||TIME|
|SOURCE||ENVIRONMENTALMEDIA||POINT OFEXPOSURE||ROUTE OFEXPOSURE||EXPOSEDPOPULATION|
|Groundwater||site sludge/soil||groundwater||private wells||ingestion||site residents||past|
|Groundwater||site sludge/soil||groundwater||municipalwells||ingestion||site residents||past|
|Biota||site sludge/soil||surface water||biota||ingestion||individualsinvolved inwildlife|
|ingestion||consumers ofmeat ofdairyproducts||past|
|Surface Water||site soil||surface water||surface water||dermal||recreationalsurface waterusers||past|
|Sediment||site soil||sediment||surface water||dermal||recreationalsurface waterusers||past|
Potential exposure pathways are indicated if exposure to a contaminant could haveoccurred, could be occurring, or could occur in the future.
As there is no containment system, overland flow is available to migrate into irrigationditches and subsequently into channels leading to the Rio Grande. There are no drinkingwater intakes in these surface water bodies. Biota may be affected if contaminants arebioaccumulated into the food chain. In addition, recreational users of surface water bodiesmay become dermally exposed to contaminants. However, level of contamination in thesurface water is not known.
As discussed in the Pathways Analyses section, no completed exposure pathways seem toexist that can be linked to the site. Contaminants have been found in private wells off-site,although the relationship of those contaminants to the site cannot be established. Additionally, whether the maximum levels of contaminants were found in a well which isbeing used for drinking water has not been established. Potential exposures may resultfrom ingestion of contaminated water used for drinking. Health effects of exposure tocontaminants via the other potential pathways mentioned will not be discussed because it isunlikely that those exposures would be at levels of public health significance. The merepresence of a contaminant does not imply that harm will result from exposure. ATSDRstaff determines whether a contaminant might be of concern by estimating the exposuredose a person using the well for drinking water might receive, and comparing that dosewith doses people and animals received in studies in the literature. A contaminant at aconcentration that would result in an estimated exposure dose significantly lower than thelowest dose known to cause health effects, or significantly lower than the highest doseknown not to cause health effects, should pose no appreciable public health hazard. Significantly lower means up to several orders of magnitude lower (an order of magnitudeis ten times), depending on certain factors such as uncertainty in the study, or assumptionsmade about people based on animal studies.
The Toxicological Evaluation portion of this section will discuss possible health hazardsfrom exposure to the contaminants of concern, 1,1-dichloroethene, 1,1-dichloroethane, and1,2-dichloroethane, in private wells off the site. Although the tetrachloroethene level in aprivate well exceeded ATSDR's comparison value, ATSDR staff estimated the exposuredose and concluded that it is of no public health significance. As the contaminants1,1-dichloroethene, 1,1-dichloroethane, and 1,2-dichloroethane have not been found on thesite, they may not be related to the site. Health outcome data will be addressed in theHealth Outcome Data Evaluation section and Community Health Concerns in theCommunity Health Concerns Evaluation section.
Contaminated well water users may ingest 1,1-dichloroethene (DCE), 1,1-dichloroethane(1,1-DCA) and 1,2-dichloroethane (1,2-DCA). The maximum levels detected in privatewells in the San Jose area are 2.5 ppb DCE, 10.8 ppb 1,1-DCA, and 1.6 ppb 1,2-DCA. It isnot known whether these maxima are in wells being used for drinking water. Thiscontamination may not be site related.
DCE is considered a possible human carcinogen by EPA because of limited evidence thatDCE can cause cancer in animals experimentally exposed. There is inadequate evidencethat DCE can cause cancer in people. The International Agency for Research on Cancerconsiders DCE not classifiable as to human carcinogenicity (12).
ATSDR used available data to estimate the increased cancer risk associated with exposureto DCE in private wells in the San Jose community. The maximum level of DCE foundrepresents a slight increased risk of cancer for persons ingesting the water regularly for alifetime. However, this slight increased risk is very uncertain for several reasons. It is notknown whether the maximum level of DCE found in a private well is representative of DCElevels in wells used for drinking water. It is not known whether anyone has been drinkingwell water for a lifetime. Finally, the scientific community is divided on whether DCE isreally capable of causing cancer in people.
The maximum DCE concentration detected in well water in the San Jose community issignificantly below levels known to cause health effects other than cancer (12). Therefore,non-carcinogenic adverse health effects related to DCE exposure would not be expected.
1,1-DCA is considered a possible human carcinogen, because some studies suggest that ratsand mice experimentally exposed to 1,1-DCA developed cancers. These studies, however,are not conclusive due to poor survival in both the exposed and the unexposed (control)animals (13). There is no information about people exposed to 1,1-DCA (13). Themaximum 1,1-DCA concentration detected in well water in the San Jose community issignificantly below levels known to cause health effects including cancer (13). Therefore,adverse health effects related to 1,1-DCA exposure would not be expected.
1,2-DCA is considered a probable human carcinogen, because, in some studies, rats andmice experimentally exposed to DCA developed tumors. There is inadequate informationabout people exposed to 1,2-DCA (14). ATSDR used available data to estimate theincreased cancer risk associated with exposure to 1,2-DCA in private wells in the San Josecommunity. The maximum level of 1,2-DCA found represents no increase in risk of cancerfor persons ingesting the water regularly for a lifetime. The maximum 1,2-DCAconcentration detected in well water in the San Jose community is significantly below levelsknown to cause health effects other than cancer (14). Therefore, non-carcinogenic adversehealth effects related to 1,2-DCA exposure would not be expected.
No health outcome databases were evaluated for this site for the following reason: there areno completed exposure pathways, and the only potential completed pathway represents apossible slight increased cancer risk over a lifetime for one private well. Only one well inthe AT&SF area is known to be contaminated, although levels and usage patterns are notknown. Therefore, the potentially exposed population is limited to the people using onewell. This number of people is too small and specific to pick out of the tumor registry.
Residents voiced their site-related health concerns at the ATSDR-sponsored publicavailability sessions in June, 1993. ATSDR recommends that when people experiencehealth effects, they consult with their health care practitioner. We address the specificconcerns as follows:
- Cancer; specifically, brain, stomach and colon cancers and leukemia, as well as cancer ingeneral. Cancer is a group of diseases characterized by rapid, uncontrolled growth of tissuethat invades adjacent structures and can spread to distant areas of the body. Manycancerous tumors can cause death if not adequately treated. Although many malignantdiseases are grouped together as cancer, they are actually different conditions with distinctcauses and outcomes. For example, colon cancer is associated with a low-fiber, high-fatdiet, and basal cell carcinoma is associated with sun exposure. Colon cancer can spreadthroughout the body, eventually causing death; basal cell carcinoma may never spread todistant body sites or cause death. Based on available data, ATSDR staff consider itextremely unlikely that cancers in community members are related to exposure tocontaminants at the AT&SF site. This conclusion may be reevaluated if more data becomeavailable. Refer to the Toxicologic Implications section for a discussion about cancer andexposure to contaminated well water in the San Jose community.
- Allergies, skin rashes, respiratory problems, headaches. These health effects are commonlyseen in most American communities. It would be extremely unusual for an individual tohave health effects such as these from being exposed to the contaminants at the levels foundin private wells.
- Lupus. Lupus erythematosus is a disease of the connective tissue. Evidence indicates it isan autoimmune disorder, where the immune system appears to react to the body's owntissues as if they were harmful invaders. Lupus occurs five to ten times more frequently infemales than males, predominantly in the 15-to-55-year age group (15). There is noevidence suggesting that lupus results from exposure to environmental toxins such as thosefound at AT&SF. It is predominantly a genetic disease.
- Safety of drinking water. Because of the vast amounts of polluted groundwater in theAlbuquerque area, people who drink water from a private well should have their welltested periodically. Contaminated water should not be used for drinking. Of the 14 wellstested in the San Jose community, ten were free of contamination and, of the remainingfour, extremely low levels of carcinogens were found. Refer to the ToxicologicalImplications section for a discussion about cancer and exposure to contaminated well waterin the San Jose community.
- Safety of future crops raised on lands adjacent to the site, and safety of ingesting the milkof dairy cattle fed those crops in the future. ATSDR staff assumed that water such as thatfound in the on-site monitoring wells would be used to irrigate the crops. This water iscontaminated with relatively low levels of PAHs and xylenes. PAHs and xylenes at theselevels will not be taken up by the roots into the leaves of crops such as alfalfa; however,PAHs will adsorb onto the leaves of crops if they are sprayed onto the leaves, for exampleby spraying contaminated water onto leaves (16). Contaminants accumulate in the soil thisway, too. In the case where water contaminated with carcinogenic PAHs is used to raisefodder for dairy cows, these contaminants will eventually show up in the milk. Irrigationwater highly contaminated with carcinogenic PAHs should not be used for watering crops. Non-carcinogenic PAHs and xylenes will not affect the quality of the milk of cows fed thealfalfa. ATSDR staff reviewed available data regarding levels of carcinogenic PAHs ingroundwater and determined that it is not sufficiently contaminated to be of health concernif used to irrigate alfalfa crops.
In addition, the report entitled Residents' Perceptions of Health Concerns andEnvironmental Degradation of the San Jose Community of Albuquerque, New Mexicoindicates a concern about stomach and digestive problems. Like the allergies and otherhealth effects discussed above, stomach and digestive problems are commonly seen in mostAmerican communities. It would be extremely unusual for an individual to have healtheffects such as these from being exposed to the contaminants at the levels found in privatewells.