Review of the U.S. Navy Environmental Health Center's Health-Hazard Assessment Process (2000)

THE NAVY AND MARINE CORPS use a large number of chemicals on land at shore facilities, in the air in combat and reconnaissance aircraft, on seas around the world in surface vessels, and in submarine vessels that operate as self-contained environments. Although many of the chemicals used by the Navy might be relatively innocuous, the Navy does use a large number that can pose significant health hazards under specific exposure circumstances.

The Navy Environmental Health Center (NEHC) is the primary organization within the Navy that is tasked with assessing occupational and environmental health hazards for Navy personnel from exposures to toxic substances. It serves as the central source that provides the Navy and Marine Corps, ashore and afloat, with technical support for preventive medicine, medical management, health promotion, drug screening, and occupational and environmental health programs. For many of these programs, NEHC reviews toxicological and related data and prepares health-hazard assessments (HHAs) for potentially hazardous materials under a variety of exposure conditions. Because NEHC is continually being asked to develop HHAs for the Navy and the Marine Corps, and because the Navy is committed to protecting its personnel from exposures to toxic chemicals, the National Research Council (NRC) was asked to assess independently the validity and ef-

fectiveness of NEHC's HHA process¹; to determine whether the process as implemented provides the Navy with the state-of-the-art, comprehensive, and defensible evaluations of health hazards; and to identify any program elements that require improvement.

The NRC assigned this project to the Board on Environmental Studies and Toxicology's Committee on Toxicology (COT). COT convened the Subcommittee on Toxicological Hazard and Risk Assessment, which prepared this report. The subcommittee has expertise in general toxicology, inhalation toxicology, epidemiology, neurotoxicology, immunotoxicology, reproductive and developmental toxicology, pharmacology, medicine, risk assessment, and biostatistics.

The subcommittee's assessment of NEHC's HHA process is based on its review of documents submitted by NEHC; presentations made by NEHC personnel at subcommittee meetings; and site visits to NEHC in Norfolk, Virginia, and the aircraft carrier, U.S.S. Constellation, while docked at the Naval Air Station North Island, San Diego, California. In addition, the subcommittee reviewed the HHA processes used by some chemical and pharmaceutical companies for their adaptability and usefulness to the Navy's situation.

The subcommittee has reviewed NEHC's HHA process and concludes that NEHC has generally done an adequate job preparing routine HHAs, considering the NEHC's available resources. Several deficiencies are noted, however, especially for conducting complex HHAs. The deficiencies include (1) the lack of formal, written, standard operating procedures (SOPs) for preparing HHAs, (2) inadequate in-house staff expertise for preparing complex HHAs, (3) inadequate availability

of electronic databases, (4) inadequate quality-assurance and quality-control procedures, (5) inadequate coordination and information transfer between NEHC and other stakeholders, and (6) inadequate medical surveillance as well as the absence of a centralized medical-data management structure. The subcommittee's conclusions and recommendations with respect to each of these deficiences are discussed below.

In reviewing the NEHC's procedures for conducting HHAs, it became apparent to the subcommittee that no formal procedures (e.g., SOPs, including flow charts) have been developed as to how HHAs should be prepared and documented. To improve procedures currently used by NEHC, the subcommittee recommends that NEHC utilize procedures established in industry (e.g., pharmaceutical and chemical companies), governmental agencies, and other organizations. The subcommittee recommends that NEHC develop a set of SOPs for the preparation of its HHAs by incorporating the relevant aspects of procedures employed by those groups.

The subcommittee also recommends that the NEHC develop guidelines or criteria for developing HHAs or for deferring a review to NEHC, for use by industrial hygiene personnel on ships or at regional occupational health departments.

The effectiveness of the NEHC's HHA program is dependent on the training and expertise of the personnel tasked to develop HHAs. The subcommittee believes that much of the work performed by the NEHC can be carried out by scientists or industrial hygienists at the bachelor or master of science level. The subcommittee concludes that the current education and experience level of NEHC staff is adequate for preparing routine HHAs. However, there were a few complex risk-assessment projects, such as those that involved determining the health hazards associated with off-gassing of chemicals in submarines, which

required personnel that are more highly trained in toxicology, industrial hygiene, epidemiology, and human risk assessment. The subcommittee recommends that NEHC recruit additional scientists with expertise in toxicology, epidemiology, and risk assessment for conducting such complex tasks. The subcommittee also recommends that all naval operations handling hazardous chemical substances should have an adequate level of access to industrial hygiene personnel. This expertise needs to be commensurate with the size of the facility. For example, large facilities (such as an aircraft carrier that accommodates up to 5,000 naval personnel) should have more than one industrial hygienist to support the continuous or sustained operations typical for deploying naval vessels, and in case one of the officers becomes ill, injured, or transferred. Small facilities, such as a submarine, on the other hand, would only need periodic access to such personnel.

Because of budget reductions in the Navy, the combination of decreasing numbers of experienced staff and an increasing demand for greater number of HHAs requires development of a more effective approach for conducting HHAs. The subcommittee recommends that the NEHC develop a long-term strategy to deal with increasing demand for services in the face of decreasing resources. This strategy would include elements such as streamlined processes to conserve staff time; increased training of current staff to keep up to date with advances in toxicology and risk assessment; and development of a workforce planning strategy that would include a succession plan for NEHC staff and a projection of future personnel needs, along with minimal training and experience requirements for each position. Particular attention should be given to the qualifications necessary for personnel exercising key technical oversight review function for HHAs.

Based on its review of the information sources currently available to key NEHC staff for conducting HHAs, the subcommittee concluded that there is an absence or limited availability of computerized hardware and software for accessing electronic information databases. Routine access to such databases is needed to ensure that the most up-to-date information is obtained for preparing HHAs. The absence of a data-management structure also impedes meaningful analysis of the

vast array of existing data available throughout the Navy on chemicals, exposures, and health outcomes. The subcommittee recommends that NEHC staff be provided with, and trained to use, up-to-date computer hardware and software for conducting electronic searches. In addition, the subcommittee recommends that NEHC develop a literature-search strategy for obtaining the most up-to-date information. In-depth literature searches should be performed for new or experimental compounds or substances, whereas less comprehensive searches are needed for chemicals or substances that are in common use (e.g., cleaning supplies and certain paints).

NEHC currently relies heavily on SmartRisk/SmartTox® assessment software and Material Safety Data Sheets (MSDSs) when conducting HHAs. The subcommittee recommends that NEHC not rely solely on these sources. Although it is appropriate to begin an assessment with consideration of the MSDSs, all data contained in them should be independently confirmed before their use. SmartRisk/SmartTox® software is of limited usefulness when evaluating the toxicity of compounds, because the information contained in it might not be current and must be updated periodically.

There are a number of highly credible information sources on the toxicology of industrial and commercial compounds that could provide valuable technical input in this context. Many are already used to some extent by the NEHC HHA staff. Examples include the U.S. Environmental Protection Agency (EPA) Integrated Risk Information System, Health Effects Assessment Summary Tables, the Hazardous Substances Data Base (HSDB), Registry of Toxic Effects, the Agrochemicals Handbook (Royal Society of Chemistry 1994), Sax's Dangerous Properties of Industrial Materials (Lewis 1996), Patty's Industrial Hygiene and Toxicology (Clayton and Clayton 1993), the International Agency for Research on Cancer (IARC) series, and the Air Force toxicology guide Installation Restoration Program Toxicology Guide (ORNL 1989, 1990). The EPA Exposure Factors Handbook can be consulted for updated exposure factors.

To avoid duplication, NEHC should explore the use of additional authoritative sources, such as existing hazard and risk assessments conducted by other Department of Defense (DOD) and governmental organizations, private organizations, and those available in the open literature. Examples include acute exposure guideline levels (AEGLs) developed by the National Advisory Committee on AEGLs (these documents are also reviewed by COT), carcinogenicity evaluations pre-

pared by IARC, and documents prepared by COT such as spacecraft maximum allowable concentrations (SMACs), emergency exposure guidance levels (EEGLs), and continuous exposure guidance levels (CEGLS). For repeated exposures, the Navy should also routinely review threshold limit values proposed by the American Conference of Governmental Industrial Hygienists, and the workplace environmental exposure limits proposed by the American Industrial Hygiene Association.

The subcommittee concludes that the NEHC's HHA program has inadequate formal quality-assurance and quality-control (QA/QC) procedures. The subcommittee recommends that NEHC establish a QA/QC program to (1) review and maintain updated SOPs for developing HHAs, and (2) ensure that HHA documents developed by NEHC, staff, and contractors are scientifically sound and instructive.

To ensure the scientific accuracy of HHA reports, the subcommittee recommends that a system be developed for regular peer review of HHAs by qualified internal and external reviewers. This system should include criteria for determining whether an HHA would undergo external or internal review and what types of expertise and institutions are needed to perform such reviews, and for documenting the process and its results.

This review would help to ensure scientific rigor and objectivity and provide an opportunity for staff to obtain additional perspective from scientists outside the Navy. Furthermore, the subcommittee recommends that a peer review board be established to provide a periodic external review of NEHC's HHA process. The board should be an independent body comprised of scientists possessing experience in industrial hygiene, toxicology, and risk assessment.

The subcommittee observed that there is little or no communication between the NEHC's HHA program and its clients in various Navy

commands. The subcommittee recommends that the NEHC establish and implement systematic customer survey and feedback mechanisms to determine utility and timeliness of its HHAs in decision making, and to obtain suggestions for improvement to better serve the needs of its clients or customers (e.g., Naval Sea Systems Command).

The subcommittee believes that there is a need for greater coordination and information transfer between the NEHC and other Navy or governmental bodies that also perform HHAs. This interaction could provide insight for addressing issues and solving problems that may be common between institutions. NEHC would benefit by interacting more with the U.S. Army Center for Health Promotion and Preventive Medicine; the U.S. Air Force's Institute for Environmental Safety and Occupational Health Risk Analysis at Brooks Air Force Base, Texas; Triservice Toxicology Research Laboratories at Wright-Patterson Air Force Base in Ohio; United States Environmental Protection Agency; Occupational Safety and Health Administration; National Institute for Occupational Safety and Health, and the U.S. Department of Energy.

The subcommittee recommends that the NEHC actively communicate the findings and recommendations of HHA reports to a wide array of stakeholders throughout the service, ranging from the client of the HHA to the staffs of the health, safety, and environmental programs. In addition, the basic HHA information should also be made available to all naval personnel and civilian and contract workers, and to the lay public.

The Navy's Bureau of Medicine and Surgery collects medical data on Navy personnel. A centralized medical-data management system is being developed for the entire DOD and will eventually include both occupational medicine and industrial hygiene data. Such a system would allow NEHC to access medical data to conduct Navy-wide surveillance studies to detect possible adverse health outcomes related to potential chemical exposures.

The centralized approach for data collection and processing would facilitate communication between various commands within the Navy, such as between NEHC and industrial hygiene personnel at remote locations. Data from the medical-surveillance program should be ana-

lyzed by NEHC to evaluate the effectiveness of HHAs in protecting the health of naval personnel on a regular basis. Medical records can be used to verify the effectiveness of the HHA program and its recommendations.

The Industrial Hygiene Directorate's HHA program is designed to protect the health of naval personnel. In a reduced-size Navy, the preventive functions of the NEHC can be an important factor in reducing costs associated with Navy health care and readiness. At present, NEHC's HHAs provide advice only. The subcommittee recommends that the Navy consider elevating the importance of the HHA program (e.g., by delegating authority to the NEHC for “signing off” on decisions to use or not use products) and increasing support for the HHA program throughout the Navy command structure.

The subcommittee concludes that the development of formal, written SOPs; the addition of senior scientists with expertise in toxicology, epidemiology, risk assessment and industrial hygiene; increased training of the current staff; better quality control and quality assurance procedures, including the formation of a peer review board; improvements in data acquisition and management; increased communication between NEHC and other DOD agencies and stakeholders; and the development of a centralized medical-data management system would lead to a more effective HHA process that would stand up to critical and objective scrutiny.

Review of the U.S. Navy Environmental Health Center's Health-Hazard Assessment Process