OFFICE OF INSPECTOR GENERAL 

Catalyst for Improving the Environment 

Quick Reaction Report 

EPA Needs to Plan and Complete a 

Toxicity Assessment for the Libby 

Asbestos Cleanup 

Report No. 2007-P-00002 

December 5, 2006 
Abbreviations 

ATSDR Agency for Toxic Substances and Disease Registry 

CAG Community Advisory Group 

EPA U.S. Environmental Protection Agency 

NCP National Contingency Plan 

NPL National Priorities List 

NTP National Toxicology Program 

OIG Office of the Inspector General 

OSWER Office of Solid Waste and Emergency Response 
U.S. Environmental Protection Agency 2007-P-00002

Office of Inspector General December 5, 2006

At a Glance 

Catalyst for Improving the Environment 

Why We Did This Review 

At the request of both Montana 

Senators, the Office of Inspector 

General (OIG) initiated this review of 

the U.S. Environmental Protection 

Agency’s (EPA’s) efforts to clean up 

amphibole asbestos contamination in 

Libby, Montana. We are issuing this 

quick action report to bring EPA 

management’s immediate attention to

significant, time-critical issues we 

identified during our limited review. 

Background 

After 1999 media reports called 

attention to Libby citizens’ health 

problems, EPA officials requested 

that we review EPA’s actions. Also 

in 1999, EPA began a cleanup of 

Libby asbestos contamination. In 

January 2000, due to citizen 

concerns, EPA started sampling and 

analyzing lawn and garden products 

that contained vermiculite. In 

March 2001, we reported that EPA 

had addressed asbestos contamination 

at other sites, but failed to institute 

regulations or other controls that 

might have protected Libby’s citizens 

from the health effects of asbestos 

contamination. In 2002, EPA began 

an emergency response cleanup of 

Libby residential and commercial 

properties. 

For further information, contact our 

Office of Congressional and Public 

Liaison at (202) 566-2391. 

To view the full report, 

click on the following link: 

www.epa.gov/oig/reports/2007/ 

20061205-2007-P-00002.pdf 

EPA Needs to Plan and Complete A Toxicity 

Assessment For the Libby Asbestos Cleanup 

What We Found 

In our limited review, we identified the following significant issues that we 

believe are critical to a successful cleanup in Libby, Montana. 

• EPA has not completed a toxicity assessment of amphibole asbestos 

necessary to determine the safe level for human exposure; therefore, 

EPA cannot be sure that the Libby cleanup sufficiently reduces the risk 

that humans may become ill or, if ill already, get worse. 

• EPA’s public information documents Living with Vermiculite and 

Asbestos in Your Home are inconsistent about safety concerns. 

What We Recommend 

We recommend EPA: 

• Fund and execute a comprehensive amphibole asbestos toxicity 

assessment to determine (1) the effectiveness of the Libby removal 

actions, and (2) whether more actions are necessary. The toxicity 

assessment should include the effects of asbestos exposure on children. 

The EPA Science Advisory Board1

 should review the toxicity 

assessment and report to the Office of the Administrator and the Libby 

Community Advisory Group whether the proposed toxicity assessment 

can sufficiently protect human health. 

• Review and correct any statements that cannot be supported in any 

documentation mailed or made available to Libby residents regarding the 

safety of living with or handling asbestos until EPA confirms those facts 

through a toxicity assessment. 

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 Congress established the EPA Science Advisory Board in 1978, in part, to review the guidelines governing the use of scientific and 

technical information in regulatory decisions. 
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF 

INSPECTOR GENERAL

December 5, 2006 

MEMORANDUM 

SUBJECT: EPA Needs to Plan and Complete a Toxicity Assessment for the 

Libby Asbestos Cleanup 

Report No. 2007-P-00002 

TO: Marcus Peacock 

Deputy Administrator 

Susan Parker Bodine 

Assistant Administrator for Solid Waste and Emergency Response 

Robbie Roberts 

Region 8 Administrator 

This report contains time-critical issues the Office of Inspector General (OIG) identified during 

the limited work performed on this review, and proposes corrective actions. This report 

represents the opinion of the OIG and does not necessarily represent the final position of the U.S. 

Environmental Protection Agency (EPA). EPA managers will make final determinations on 

matters in this report. 

Action Required 

Please provide a written response to this report within 30 calendar days. You should include a 

corrective action plan for agreed upon actions, including milestone dates. We have no objections 

to the further release of this report to the public. This report will be available at 

http://www.epa.gov/oig. 

You may contact me at (202) 566-0847 or roderick.bill@epa.gov, or Eileen McMahon at 

(202) 566-2391, if you have any questions concerning this report. 

Sincerely, 

Bill A. Roderick 

Acting Inspector General 
Purpose 

On August 22, 2006, the Office of Inspector General (OIG) initiated a project to review EPA’s 

efforts to clean up amphibole asbestos contamination in Libby, Montana (Region 8). The 

impetus for the review was two congressional requests to evaluate whether potential problems 

exist with the Libby asbestos National Priorities List (NPL) site cleanup. In our limited work to 

date, we identified some issues, which we believe to be of imminent concern, and are presenting 

them in this report. 

The preliminary review objective was to determine whether the U.S. Environmental Protection 

Agency’s (EPA’s) Office of Solid Waste and Emergency Response (OSWER) and Region 8 

personnel developed and executed an effective cleanup based upon Federal requirements that 

protect human health. However, once we determined that EPA had not followed its own 

guidance regarding the conducting of a toxicity assessment, we felt it necessary to bring the issue 

up for immediate attention and resolution because – as reported to EPA by the Agency for Toxic 

Substances and Disease Registry (ATSDR) in their assessment on public health in Libby in 2003 

– “people in the Libby area have elevated levels of disease, and death, associated with exposure 

to asbestos.” 

Background 

The National Contingency Plan (NCP) governs the clean up of NPL sites. The NCP requires 

EPA conduct a remedial investigation and a (baseline) risk assessment for all NPL sites. The 

NCP designates ATSDR, a component of the Department of Health and Human Services, as the 

responsible agency for performing public health assessments for NPL sites. The NCP also states 

that the responsible agency shall keep the public informed about the cleanup progress. 

On May 28, 2003, ATSDR released the final version of its report, Public Health Assessment for 

the Libby NPL site, Operable Unit 4, Town of Libby and Affected Libby Valley Residential and 

Commercial Properties. The report concluded in part, that the citizens of Libby were exposed to 

hazardous levels of asbestos, and had elevated levels of disease and death from exposure to 

asbestos. It also recommended, in part, that EPA conduct a toxicological investigation (toxicity 

assessment) and epidemiology studies. (See more information about asbestos in Appendix A, 

Background of Libby Asbestos.) 

Toxicology. In their Public Health Assessment report, ATSDR defines toxicology as the study 

of the harmful effects of chemicals on humans or animals.2 The National Toxicology Program 

(NTP), a component of the Department of Health and Human Services, states that they generally 

perform tests on rodents to determine the toxicity of substances. 

Epidemiology. ATSDR’s Public Health Assessment report also defines epidemiology as the 

study of different factors that determine how often, in how many people, and in which people 

2

 This sentence, corrected in January 2007, originally stated the definition as “the study of the harmful effects of 

chemicals on humans and animals.” 

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disease will occur. The NTP states that toxicology studies along with epidemiology studies are 

the best means available for identifying potential human hazards. 

Superfund cleanups go through two phases before they are considered complete: the emergency 

response phase and the remedial action phase. While in the emergency response mode, the 

emphasis is on removing “hot spots,” or areas of high contamination. During the remedial action 

mode of a Superfund cleanup, risk is established through a formal, step-by-step, scientific 

process for quantifying health risks to humans called a risk assessment. 

OSWER staff and EPA Region 8 personnel acknowledge the importance of the toxicity 

assessment. Specifically, Region 8 defines the risk assessment as a formal step-by-step scientific 

process for quantifying human health risks. Region 8’s Human Health Risk Assessment 

procedures for Libby asbestos identify the toxicity assessment as central to completing the risk 

assessment. 

Scope and Methodology 

We conducted our review from August 22, 2006, to November 22, 2006. However, many of the 

significant facts surfaced during a related OIG investigation, which began on March 9, 2006, and 

is ongoing. We included this data in our review as well. We interviewed (or obtained responses 

from) EPA’s OSWER (senior officials and staff) and Region 8 personnel, and obtained 

documents related to the issues dated from 1990 to 2006. We are issuing this quick action report 

to bring to management’s immediate attention significant issues we identified during our initial 

review. Specifically, the objective of this quick action report is to ensure that EPA fully 

considers the role of toxicology in the remaining clean up of asbestos contamination in Libby. 

Preliminary Findings 

EPA has neither planned nor completed a risk and toxicity assessment of the Libby amphibole 

asbestos to determine the safe level of human exposure. Thus, EPA cannot be sure that the 

ongoing Libby cleanup is sufficient to prevent humans from contracting asbestos-related 

diseases. Also, EPA presented inconsistent positions on safety issues in two public information 

documents. EPA issued Living with Vermiculite to Libby residents in October 2003; the other, 

Asbestos in Your Home, is now on the EPA Internet Website. 

Risk and Toxicity Assessments 

EPA personnel stated that the Libby cleanup, which began in 1999, was limited to removing the 

most visible and prevalent signs of danger to the community. We agree that it was appropriate to 

conduct these initial cleanup actions, and they should continue. However, EPA has no way to 

determine whether the initial removals sufficiently reduced the risk that Libby residents would 

become ill or get sicker. EPA personnel informed us that this is the case because EPA had not 

completed an amphibole asbestos risk assessment. A risk assessment includes: 

• data collection (site, history, exposure potential, contaminant type and distribution), 

• exposure assessment (how much and in what ways exposure can occur), 

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• toxicity assessment (potential of the contaminants to cause harmful effects to 

humans), and 

• risk characterization (integrates previous steps to calculate risk to humans). 

The key element of the risk assessment, which the Agency has not completed, is the toxicity 

assessment. A toxicity assessment is necessary to determine the safe level of amphibole asbestos 

exposure for humans. 

OSWER Studies of Libby Asbestos 

We have had extensive conversations and correspondence with OSWER officials regarding 

EPA’s nonperformance of a toxicity assessment of the Libby asbestos. OSWER officials 

responded that a toxicity assessment was proposed but denied for two reasons: (1) EPA did not 

approve the budget request and (2) OSWER believed that they could obtain the information they 

needed to determine the toxicity of Libby asbestos based on other epidemiology studies 

(completed and ongoing). 

OSWER Epidemiology Work. As evidence that they did not ignore Libby asbestos toxicity 

assessment work, OSWER officials cited EPA’s funding, for several years, a number of efforts 

to assess hazard and risk. Those efforts included various epidemiological studies, and the 

updating of the Integrated Risk and Information System for cancer and non-cancer endpoints. 

However, that work does not include ATSDR defined toxicology (animal) studies. In addition, 

OSWER staff, as distinguished from OSWER officials, stated that: 

• The work ongoing and planned was not sufficient to determine the toxicity of the Libby 

asbestos. 

• A toxicity assessment could take up to 2 years and should include assessing the effects of 

amphibole asbestos exposure on children. 

Benefits of Toxicology and Epidemiology. Toxicology and epidemiology are not the same 

although they share the same goal of determining the hazardous effect of a substance on humans. 

Toxicology specifically determines the harmful effects on humans through animal testing. 

Epidemiology attempts to forecast how often a person gets sick, who gets sick, and how many 

people get sick. The NTP suggests that together, toxicology and epidemiology are the best 

means available for identifying potential human hazards. ATSDR agrees with the NTP 

suggestion that the studies together would be protective of human health. In their Public Health 

Assessment report, ATSDR: 

• Concluded that Libby residents could still be exposed to hazardous levels of asbestos, and 

that these levels could be especially hazardous to sensitive populations (adults previously 

exposed or who smoked, and young children). 

• Recommended that EPA conduct a toxicity assessment to help determine whether the 

chemical makeup and fiber size found in Libby pose additional risks. 

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In addition, an ATSDR official stated the epidemiology studies alone could not reliably provide 

this information due to the uncertainty associated with determining the level and duration of 

Libby asbestos exposure in individuals who are tested. 

Therefore, we do not agree that OSWER can characterize epidemiology work as toxicology 

work, or that epidemiology work alone is sufficient to protect human health. We do agree that 

the epidemiology work is a key component in protecting human health in Libby, and that work 

should continue. 

OSWER Guidance. OSWER has not ruled out performing a toxicity assessment in the future; 

however, they stated that in the guidance they prefer to use, a toxicity assessment was not 

necessary. Specifically, OSWER cited EPA’s March 2005 Guidelines for Carcinogen Risk 

Assessment: 

“When human data of high quality and adequate statistical power are available, 

they are generally preferable over animal data and should be given greater weight 

in hazard characterization and dose-response assessment, although both can be 

used.” 

Additionally, OSWER cited EPA’s December 2002 A Review of the Reference Dose and 

Reference Concentration Process: 

“Adequate human data are the most relevant for assessing risks to humans. When 

sufficient human data are available to describe the exposure-response relationship 

for an adverse outcome(s) that is judged to be the most sensitive effect(s), 

reference values should be based on human data.” 

Neither document is official policy for EPA personnel. Specifically: 

• Guidelines for Carcinogen Risk Assessment does not establish any substantive rules and 

has no binding effect on EPA and any regulated entity. 

• A Review of the Reference Dose and Reference Concentration Process is a review, not 

guidance, but makes recommendations that users should consider. 

We agree that human studies would provide better data; however, ATSDR recognized that, for 

ethical reasons, personnel could not perform toxicity tests on humans. Further, the documents do 

not discourage the use of animal studies; rather, they state their importance and how researchers 

can use animal data with, or instead of, human data. Specifically: 

• Guidelines for Carcinogen Risk Assessment states that epidemiologic (human) studies 

that show elevated cancer risk that correspond to findings in animal studies strengthen the 

evidence of human carcinogenity. The document also states that actual exposure 

measurements are not available for many retrospective (past events) epidemiology 

studies, which could lead to misclassifications (individuals placed in the incorrect 

exposure group). That in turn could reduce the reliability of the epidemiology study. 

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• A Review of the Reference Dose and Reference Concentration Process states that when 

sufficient human data are not available, users must employ animal studies. However, it 

would be advantageous to compare the animal data with human data even if the human 

data is not quantifiable to determine whether toxicity occurs in the same organs and the 

nature of the effect is similar. 

Communication with Libby Residents 

Region 8 personnel stated that because EPA does not know the toxicity of amphibole asbestos, 

EPA cannot substantiate the accuracy of any communication with Libby residents that says that 

the removal process eliminated the danger of contracting asbestos-related diseases. Region 8 

recently changed the leadership managing the Libby removal process. The new Remedial 

Program Manager stated that he has not reviewed all the communications that his predecessor 

had with Libby residents. 

Living with Vermiculite 

In Living with Vermiculite, EPA recommended that Libby homeowners not disturb asbestos 

because no guidelines exist on what is or is not safe. However, the document then states that 

homeowners would have little risk of exposure if they handle asbestos to clean up an undefined 

small release of asbestos. We believe this recommendation is inconsistent with the uncertainty 

of the dangerous levels of exposure. Potentially, Libby homeowners could expose themselves to 

dangerous levels of amphibole asbestos if they interpret the document to mean that no significant 

risks exist. 

Asbestos in Your Home 

Asbestos in Your Home, a document on the EPA Internet Website, was a product of a workshop 

with the American Lung Association and the Consumer Product Safety Commission. It provides 

information similar to that found in Living with Vermiculite. In this document, EPA defines a 

small release of asbestos to be no larger than a homeowner’s hand. Contrary to the EPA 

position, the American Lung Association warns that the homeowner should not attempt to 

remove or repair any level of asbestos. EPA does not address the difference in opinion with the 

American Lung Association so homeowners could make a fully informed decision regarding 

handling asbestos. 

Developments 

EPA Region 8 personnel have begun to address concerns with the Libby cleanup and EPA’s 

communications with Libby residents, as evidenced in the minutes of the August and September 

2006 Community Advisory Group (CAG) meetings, posted on EPA’s Website. Specifically, 

EPA personnel responded that new information, from toxicity assessment, might indicate that 

Libby homes may not be as safe as EPA thought and that EPA may have to do additional 

cleanup. EPA personnel agreed to participate in a panel to redraft Living with Vermiculite 

because an audience member stated that the document promoted a lackadaisical attitude toward 

the asbestos contamination. Additionally, the Acting Deputy Director for the Office of 

5 
Superfund Remediation and Technology Innovation and Region 8 personnel stated that EPA had 

removed the Living with Vermiculite document from the EPA Website on October 11, 2006, as a 

result of consultations with the CAG, and EPA is reviewing the Asbestos in Your Home 

document. We believe the actions of OSWER and Region 8 personnel, coupled with our 

recommendations, will help to ensure a swift and effective cleanup. 

Recommendations 

1. We recommend that EPA fund and execute a comprehensive amphibole asbestos toxicity 

assessment to determine (1) the effectiveness of the Libby removal actions, and (2) to 

determine whether more actions are necessary. The toxicity assessment should include 

the effects of asbestos exposure on children. The EPA Science Advisory Board should 

review the toxicity assessment and report to the Office of the Administrator and the 

Libby Community Advisory Group whether the proposed toxicity assessment can 

sufficiently protect human health. 

2. We recommend that EPA review and correct any statements that cannot be supported in 

any documentation mailed or made available to Libby residents regarding the safety of 

living with or handling asbestos until EPA confirms those facts through a toxicity 

assessment. 

6 
Appendix A 

Background of Libby Asbestos 

ATSDR is tracking the human health effects of Libby asbestos in 28 locations throughout the 

country that received over 80 percent of the Libby vermiculite. In What is Asbestos?, ATSDR 

makes the following statements regarding vermiculite and asbestos contamination in Libby 

Montana. 

Vermiculite Production. Zonolite Mountain in Libby produced vermiculite for more 

than 65 years (until 1990). The mine itself is approximately 6 miles from the town. A 

transfer facility was located approximately 3 miles from Libby. From the transfer facility, 

vermiculite was loaded on trains or trucks. Two expansion ("popping") facilities operated 

at different times within the town; these plants heated vermiculite to approximately 600 

degrees Fahrenheit to expand the crystals. One of these facilities was next to a baseball 

field, which was readily accessible to the community's children. 

Types of Asbestos. There are two general types of asbestos, amphibole and chrysotile. 

Some studies show that amphibole fibers stay in the lungs longer than chrysotile. This 

tendency may account for their increased toxicity (harmfulness to the body). Regulatory 

agencies such as EPA and the Occupational Safety and Health Administration recognize 

six asbestos minerals: chrysotile, a serpentine mineral with long and flexible fibers; and 

five amphibole (with relatively brittle crystalline fibers) minerals, actinolite asbestos, 

tremolite asbestos, anthophyllite asbestos, crocidolite asbestos, and amosite asbestos. 

Libby Asbestos. Vermiculite is usually free of asbestos. However, the vermiculite ore 

taken from a mining operation in Libby contained asbestiform (asbestos-like) amphibole 

minerals, including the regulated forms tremolite and actinolite. The vermiculite also 

contains winchite, richterite, and ferroedenite asbestos, which the U.S. does not currently 

regulate. Research has linked all of these forms to asbestos related diseases. 

Asbestos Risk Factors. The heating process released asbestos fibers from the 

vermiculite ore into the air. Inhalation of asbestos fibers suspended in air can result in 

lung diseases such as asbestosis, mesothelioma, and lung cancer. The risk of developing 

any of these diseases depends on many factors, including the type of fiber, the level and 

duration of exposure, and the smoking history of the exposed individual. 

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Appendix B 

Distribution 

Office of the Administrator 

Assistant Administrator for Solid Waste and Emergency Response 

Deputy Assistant Administrator for Solid Waste and Emergency Response 

Audit Followup Coordinator, Office of Solid Waste and Emergency Response 

Administrator, Region 8 

Deputy Administrator, Region 8 

Audit Followup Coordinator, Region 8 

Agency Followup Official (the CFO) 

Agency Followup Coordinator 

Associate Administrator for Congressional and Intergovernmental Relations 

Associate Administrator for Public Affairs 

General Counsel 

Acting Inspector General 

8