Assessment of Indoor Air in Residences Adjacent to the Red River Aluminum Site in Stamps, Arkansas
RED RIVER ALUMINUM
STAMPS, LAFAYETTE COUNTY, ARKANSAS
Residents of Stamps, Arkansas requested that the Arkansas Department of Health (ADH)evaluate indoor air quality in residences on Lowe Street located adjacent to the abandoned RedRiver Aluminum, Inc. (RRA) site to determine if air contaminant concentrations could behazardous to human health. RRA operated a secondary aluminum recycling facility from 1985until 1997 in Lafayette County, Arkansas. The RRA site is located on approximately 120 acresadjacent to the corporate limits of the city of Stamps, Arkansas.
The facility reprocessed dross, an impure aluminum surface scum from the electrolytic cells ofvarious primary aluminum smelters, to recover additional aluminum. The facility also processedrecycled aluminum. Approximately 200,000 cubic yards of saltcake, or slag, generated as a wasteproduct of this process, were stacked in mounds on approximately 9 acres of land adjacent to theeast fenceline of the facility, which borders the corporate limits of Stamps (see map, AppendixA). Saltcake piles ranged from approximately 5 feet to 50 feet in height. A buffer zoneapproximately 20 feet wide, which contained a drainage ditch, separated the saltcake moundsfrom the fenceline. Berms were placed around the saltcake to divert runoff into two holdingponds, designated the north and south holding ponds (total volume approximately 1 milliongallons). However, the ponds continued to intermittently overflow into the residential yards. Therefore, RRA constructed a 3000 foot injection well in 1992, and began injecting the contentsof the ponds into the injection well to eliminate site runoff. Pond overflow offsite continuedintermittently during this time period. In November 1997, the company ceased operations andfiled for bankruptcy in December 1998 .
Two additional health consultations have been completed at this site. Soil sample analyticalresults were evaluated in the initial health consultation to determine if exposure to contaminatedsoil in residential yards located adjacent to RRA, might cause adverse health effects. The second health consultation was conducted at this site to determine if potable water was contaminatedbecause of site-runoff. Residents living adjacent to the fenceline allege that saltcake from thestorage area blew off-site and contaminated the indoor air in residences located in the vicinity ofthe RRA site. Residents allege that site-related contaminants might have caused the followinghealth conditions: diabetes, high blood pressure, cancer (no type specified), skin, eye, andrespiratory tract irritation, asthma, and skin rashes. The purpose of this health consultation is toevaluate results of indoor air samples to determine if breathing the air might be potentially harmful to human health.
Potential exposure pathways to contaminants at the RRA site have been evaluated to determine ifpersons could be exposed to potentially unsafe contaminants. Exposure pathways consist of fiveelements:
- a source of contamination,
- transport through an environmental medium, such as soil or groundwater,
- human exposure to the contaminant(s),
- a route for the contaminant to enter the body, and
- a receptor population.
For a person to be exposed to a contaminant, the exposure pathway must contain all of theelements listed above, resulting in a completed exposure pathway. In some cases, a potentialexposure pathway might exist in which at least one of the elements of the exposure pathway ismissing, but could exist. Potential pathways indicate that exposure to a contaminant could haveoccurred, could be occurring, or could occur in the future. Potential exposure pathways refer tothose pathways where (1) exposure is documented, but there is not enough information availableto determine whether the environmental medium is contaminated, or (2) an environmentalmedium has been documented as contaminated, but it is unknown whether people have been, ormay be exposed to the medium, or may be exposed in the future. A potential completedexposure pathway exists for the inhalation route of exposure if saltcake is blown off-site into theresidential neighborhood located adjacent to the site. Indoor air samples were collected in eightresidences, located adjacent to the fenceline to represent a "worst case" scenario, to determine ifcontaminants were at levels which could cause potential adverse health effects.
On October 24-30, 2000, indoor air samples were collected from eight houses located on LoweStreet adjacent to the RRA fenceline. In addition, samples were collected on December 4 and 5,2000, from two Pride Addition houses, two houses in Stamps, and two houses located inLewisville for comparison purposes . The indoor air samples were collected using theNational Institute for Occupational Safety and Health (NIOSH) Methods 7300 and 7600. Theindoor air samples were analyzed for metals (see Appendix B: Table 1).
Air sample results were compared to the Agency for Toxic Substances and Disease Registry(ATSDR) air specific Intermediate Environmental Media Evaluation Guide (EMEG) values,Chronic EMEG values, the Environmental Protection Agency (EPA) Reference Dose MediaEvaluation Guide values, and/or the EPA Region VI Human Health Medium-Specific ScreeningLevels [2, 3].
Low levels of chromium were detected in the indoor air in all the homes sampled. Chromiumoccurs in a number of chemical forms. The most common forms are trivalent and hexavalentchromium, and the toxicity is different for each type. Hexavalent chromium is much more toxicthan trivalent chromium, and can be toxic to people at low levels. The laboratory analyses didnot distinguish trivalent chromium from hexavalent chromium. Therefore, to assume a "worstcase" scenario, chromium levels were compared to hexavalent chromium health screeningvalues. Indoor air levels were lower than the hexavalent chromium intermediate environmentalMedia Evaluation Guide (EMEG) of 1 microgram per cubic meter (ug/m3) , however the levelsexceeded the EPA Reference Concentration (RFC) of 0.1 ug/m3. ADH staff collected indoor airsamples December 4-6, 2000 at houses which were previously tested. The samples wereanalyzed for hexavalent chromium to determine if it was present in houses at unsafe levels. Nohexavalent chromium was measured in the indoor air samples from the houses. Therefore,indoor air chromium levels were compared to the EPA Risk Based Comparison (RBC) value of5,500 ug/m3 for trivalent chromium, because ATSDR has not established health screening valuesfor trivalent chromium. Chromium levels in all houses were lower than these values, and nohealth threat is expected by breathing air containing these levels of chromium.
Low levels of iron and titanium were found in one house; iron and copper in a second house, andcopper and zinc in a third house. Iron, titanium, copper, and zinc are naturally occurring andmake up the earth's crust. The indoor air samples collected in the Lowe Street, Pride Addition,Stamps, and Lewisville houses contained similar amounts of these metals. The airconcentrations of these elements were below health screening values for non-cancer endpoints. Air concentrations below these levels are unlikely to pose a health threat.
The Child Health Consideration Section recognizes that the unique vulnerabilities of infants andchildren demand special emphasis in communities faced with contamination of soil, water, airand food. Children are at a greater risk than adults from certain kinds of exposures to hazardoussubstances. They are more likely to be exposed because they play outdoors and they often bringfood into contaminated areas. They are more likely to come into contact with dust, soil, andheavy vapors close to the ground. Also, they receive higher doses of chemical exposure due tolower body weights. The developing body systems of children can sustain permanent damage iftoxic exposures occur during critical growth stages.
The unique vulnerability of children to contaminants in air was considered in conducting thishealth consultation. Adverse health effects have not been documented at the levels ofcontaminants found in the air samples.
- No apparent public health hazard exists in the houses located adjacent to the east RRAfenceline under present conditions. No adverse health effects are anticipated from indoorair exposure.
- Continue health education on an as needed basis.
ADH presented and discussed the indoor air sampling results with the residents.
ADH distributed educational materials to the residents in the Pride Addition of Stamps.
ADH conducted a public availability session so that citizens could have a forum to present theirhealth associated concerns about the site.
Future Action Plans
ADH will continue to review any new data that is received concerning RRA off-sitecontamination.
ADH will provide environmental health education to affected residents and to medical personnel as appropriate, or requested.
Chris C. Hemann
Arkansas Department of Health
ATSDR Region VI Representative:
ATSDR Senior Representative
ATSDR Technical Project Officer:
Division of Health Assessment and Consultation
- DATA CHEM Lab Report #'s 00I-2239-01;00I-2465-03; and 00I2465-04, Unpublisheddata. November and December 2000.
- ATSDR. Agency for Toxic Substances and Disease Registry. Air Comparison Values. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service.2002.
- U. S. Environmental Protection Agency (EPA), EPA Region 6 Human Health Medium -Specific Screening Levels Version 4. Dallas, TX. November 2002.
- ATSDR. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Chromium. Atlanta, GA: U.S. Department of Health and Human Services, Public HealthService. September 2002.
This Health Consultation, Assessment of Indoor Air in Residences Adjacent to the Red RiverAluminum Site in Stamps, Arkansas, was prepared by the Arkansas Department of Health undera cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation was begun.
Tammie McRae, MS
Technical Project Officer
Superfund Site Assessment Branch (SSAB)
Division of Health Assessment and Consultation (DHAC)
The Division of Health Assessment and Consultation, ATSDR has reviewed this healthconsultation, and concurs with its findings.
Sven E. Rodenbeck
for Roberta Erlwein
Section Chief, SSAB, DHAC, ATSDR
micrograms per cubic meter
|Health ScreeningValue||Notapplicable||EMEG - 1.01|
RFC - 0.12
|RBC - 1503||RBC - 1,100||RBC - 31||RBC - 1,100|
1 - Environmental Media Evaluation Guide (ATSDR)
2 - Reference Concentration (EPA)
3 - Risk Based Comparison value (EPA)
4 - Results bolded when metals were detected for ease of reading table
Metals Not Detected in Indoor Air Samples