Executive Summary

Publication Details

Health professionals need access to environmental health1 and toxicology information for many reasons. Certainly, public awareness about human health risks from chemical and biologic agents in the environment has increased dramatically in recent years. Similarly, changing trends in health care and an emphasis on prevention, coupled with increasing computer literacy, all support the need for readily available information about the impacts of hazardous substances in the environment on individual and public health. Reports in the popular press and news media have highlighted the public's concern. For example, pesticides on foods; second-hand tobacco smoke; asbestos and lead paint in homes and public buildings; dioxin contamination; occupational exposures to gasoline and other chemicals; exposure to radon and benzene; and drinking water contaminated with biologic or chemical agents are just a few of the issues that may confront the American public.

Although the public relies heavily on federal and state regulatory agencies for protection from exposures to hazardous substances, they frequently look to health professionals for information on routes of exposure and the nature and extent of associated adverse health consequences. However, most health professionals acquire only a minimal knowledge of toxicology during their education and training. As a result, their working knowledge of the adverse effects of chemicals on health and the conditions under which those effects might occur is often limited. Furthermore, with the many competing demands on health professionals' time, it is difficult, even for specialists, to keep apprised of rapidly evolving toxicology information. Thus, health professionals need ready access to toxicology and environmental health information resources to assist them with patient care. Policymakers, health advisors, researchers, health educators, and the general public also need access to this information as they pursue their own inquiries.

Established in 1956, the National Library of Medicine (NLM) was charged with improving the nation's health by collecting and providing access to the world's biomedical literature. In 1967, NLM established a specialized information program on toxicology and environmental health known today as the Toxicology and Environmental Health Information Program (TEHIP). Its mission is to provide selected core information resources and services, facilitate access to national and international information resources, and strengthen the infrastructure for toxicology and environmental health information.

In 1995, at the request of NLM, the Institute of Medicine (IOM) formed the Committee on Toxicology and Environmental Health Information Resources for Health Professionals. The committee was charged with examining the utility and accessibility2 of NLM's TEHIP program for the work of health professionals. It was asked to consider the current toxicology and environmental health information needs of health professionals and how those needs are currently being met. The committee conducted an 18-month study and received extensive input from health professionals representing a range of disciplines and expertise. These individuals met with the committee, participated in one of four focus group sessions at a committee workshop, or responded to a questionnaire developed by the committee. Additionally, NLM staff members provided the committee with information about the databases and ongoing research and development efforts at NLM.


Both the public health effects of hazardous substances and the changing trends in health care are reinforcing the need for authoritative and easily accessible information in the fields of toxicology and environmental health. Pathways of human exposure to chemicals in the environment are diverse. Chemicals in air, food, water, and soil can be inhaled, ingested, or absorbed in any number of settings. Vulnerable populations, such as children, the elderly, the chronically ill, minorities, and the poor may be at increased risk of harm related to environmental contamination because of biologic and demographic factors, including where they live.

Despite the complexities involved in studying human exposures, the roles of certain hazardous substances in the development of human disease are well-known. Environmental and occupational chemical exposures can affect all organ systems. They can cause or contribute to the development of a variety of human illness, including cancer, asthma and other respiratory diseases, reproductive disorders, neurologic and immune system impairments, and skin disease, as well as cardiovascular, renal, hepatic, and psychological disorders. The proliferation of the manufacture, transport, use, and disposal of chemicals coupled with the potential for human exposures makes it essential that health professionals have easy access to resources and information to assist them in the prevention, diagnosis, and treatment of disorders possibly stemming from exposures to hazardous substances in the environment.


Currently, the TEHIP program encompasses 16 online databases that contain bibliographic and factual information on environmental contaminants including chemical properties, carcinogenicity, exposure levels, adverse health effects, emergency treatment protocols, and federal regulations. The evolution of NLM's TEHIP program has been the result of both internal NLM commitments to developing toxicology and environmental health information resources (e.g., TOXLINE and the Hazardous Substances Data Bank) and the interests of other federal agencies in fulfilling their missions and legislative mandates (e.g., the Environmental Protection Agency's Toxic Chemical Release Inventory).

Although the budgeted funding for the TEHIP program (from federal appropriations) has remained relatively constant over the past 29 years (in fiscal year [FY] 1994, the TEHIP program's appropriated budget in current dollars was approximately $7.4 million), the TEHIP program's reimbursements from other agencies for collaborative projects have fluctuated. In FY 1992, the TEHIP program's total reimbursable budget from other agencies was $2.45 million, whereas in FY 1993 the reimbursable budget dropped by approximately 50 percent to $1.27 million. Since 1993, the reimbursable budget has remained relatively level (the FY 1995 reimbursable budget was $1.23 million).


The TEHIP databases represent only a small subset of the numerous databases containing information related to toxicology and environmental health. Responsibilities for research, regulation, and risk communication on environmental health issues are fragmented between numerous local, state, and federal government agencies, international organizations, industry, and other private-sector businesses. As a result, numerous databases that are relevant to fulfilling each organization's specific environmental health mission or goals have been developed. The committee became aware of the vast extent of information available and the utility of these information resources to health professionals. The committee believes that it is important for NLM to carry out the traditional and expert role of a library by organizing (cataloging) online information resources in toxicology and environmental health beyond the TEHIP databases and increasing health professionals' and other interested users' awareness of the relevant resources. By providing users with information on non-NLM resources (e.g., a description of the information resource and its access points), NLM will be delivering the valuable library service of providing users with the information needed to access the most relevant resource available.

The committee recommends that NLM consider expanding its traditional library services in toxicology and environmental health by organizing and cataloging the full spectrum of online toxicology and environmental health information resources.


As knowledge about the health effects of exposure to occupational and environmental chemicals increases, health professionals and other interested individuals need to be able to access and use resources that provide timely and accurate toxicology and environmental health information in an efficient and accessible manner. The committee discussed the health professional communities that potentially have information needs in toxicology and environmental health and use for the information available in the TEHIP databases. The committee realizes that the health professional community does not have homogeneous information needs and that there is a wide range of variation in access to online databases and other information resources. Potential user communities include primary care professionals and pharmacists; specialists in occupational and environmental health; emergency medicine and poison control center personnel; health science librarians and faculty at health professional schools; environmental health researchers and scientists; patients, the general public, and community organizations; and health professionals in local public health departments or in state and federal agencies.

Through committee deliberations and input provided to the committee from the focus groups and questionnaire respondents,3 the disparate nature of the 16 databases in the TEHIP program became more evident. The committee recognized that the databases are not equally useful for the work of the different segments of the health professional community. Although the committee realized that the current TEHIP complement of databases is the result of both NLM initiatives and interagency agreements and that each database fills an important information niche, the committee believes that the TEHIP program should set priorities that would allow efforts to be focused on those databases that meet the information needs of the greatest number of health professionals. This is particularly critical in light of the fact that the TEHIP program has experienced reduced funding levels from interagency agreements in recent years.

Comparable to a business marketing strategy that necessitates an understanding of the specific needs of current and potential customers prior to designing and distributing the product, this prioritization of the TEHIP program would first require a more in-depth analysis of the toxicology and environmental health information needs of health professionals. The goal of this user profile analysis would be to match, as closely as possible, the needs of health professionals with specific TEHIP databases. Upon completion of the user analysis, TEHIP program staff could not only prioritize their training and outreach efforts with an emphasis on those databases that are the most useful to health professionals but could also prioritize the resources that are devoted to the databases with the greatest utility for health professionals.

The committee recommends that NLM further expand its efforts to understand the toxicology and environmental health information needs of health professionals and the barriers they face in accessing that information by conducting a detailed user profile analysis. Additionally, the committee recommends that the results from that analysis be used to set priorities for subsequent efforts of the TEHIP program.


An important component of expanding the use of toxicology and environmental health information resources is increasing the awareness of these resources in the health professional and other interested user communities. Potential users of online toxicology and environmental health databases must be cognizant of the existence of the databases and of their content, must be computer literate (assuming that the user will perform his or her own search), and must have some familiarity with toxicology and environmental health data in order to interpret the retrieved information correctly.

Computer use is largely a matter of demographics. Younger health professionals are more likely to feel comfortable with computer use and to have become accustomed to retrieving information through computers. There is, however, a continuing need to train health professionals about specific databases and the use of health-related information resources.

Although no health professional can be expected to know the toxic effects of all chemicals, it is critical that health professionals be informed about the issues and familiar enough with the field to consider environmental and occupational exposures in assessing a patient's symptoms, making a diagnosis, answering a patient's questions, and counseling patients about environmental health risks. However, health professionals, especially clinicians, receive limited education and training in toxicology and environmental health in part because of an overcrowded and increasingly specialized curriculum. The committee supports the recommendations of several recent IOM studies (Environmental Medicine: Integrating a Missing Element into Medical Education [1995]; Nursing, Health, and the Environment: Strengthening the Relationship to Improve the Public's Health [1995]) that have focused on strategies for enhancing the environmental health content in health sciences curriculum and continuing education courses.

NLM's training and outreach efforts are primarily conducted through the National Network of Libraries of Medicine (NN/LM), a nationwide network of more than 4,500 local medical libraries (primarily hospital libraries), more than 140 Resource Libraries (primarily at medical schools), and eight Regional Medical Libraries. The medical librarians and information specialists at each NN/LM member library play an integral role in educating, training, and providing access to NLM's resources.

Additionally, the Division of Specialized Information Services (SIS) (which manages the TEHIP program) has been active in targeting outreach efforts to reach those populations that are particularly interested in environmental health information. In 1991, SIS implemented a pilot Toxicology Information Outreach Project with the objective of strengthening the capacity of Historically Black Colleges and Universities to train medical and other health professionals in the use of NLM's toxicology and environmental health information resources. Additionally, SIS is actively involved in a collaborative project between NLM and the Wheaton Regional Public Library (in Montgomery County, Maryland) that promotes access to information resources on environmental health and HIV/AIDS.

The committee believes that the TEHIP program can make significant contributions to health professionals by providing information on the wide scope of relevant toxicology and environmental health information resources. Outreach efforts should be targeted to meet the specific interests of the audience and should be expanded to utilize dissemination networks and environmental health efforts and initiatives currently underway. Utilization of the user analysis could assist NLM in focusing its outreach and training efforts on those databases that best meet the needs of the user community.

The committee recommends that NLM's training and outreach efforts in toxicology and environmental health information be increased to improve awareness and recognition of these resources. Mechanisms that may improve awareness include emphasizing the broad spectrum of toxicology and environmental health information resources, matching training to meet the specific needs of the target audiences, and expanding the use of already-existing distribution mechanisms for promoting the availability of toxicology and environmental health information.


Access to the TEHIP databases and difficulties in navigating the user interface were selected by focus group participants and those individuals responding to a committee questionnaire as two of the primary factors limiting use of the TEHIP databases. The only fully operational access method available for accessing all of the TEHIP databases is direct searching, a complex command-line method requiring considerable expertise in online searching. Grateful Med—a software program developed by NLM—provides a user-friendly interface for searching the NLM databases, however Grateful Med does not offer input screens for all of the TEHIP databases. NLM staff are in the process of developing a new approach to searching the TEHIP databases using the hypertext and graphics capabilities available through the World Wide Web.

The committee believes that to increase the use of the TEHIP databases by health professionals, it is critically important that they be easily accessible and that the user interfaces be intuitive. The pioneering efforts applied to MEDLINE should, when applicable, be incorporated into the TEHIP program. The committee recommends that a two-step approach be implemented in making refinements to the TEHIP databases and emphasizes the need for evaluation components to be incorporated and then monitored throughout this process. The first step would entail improvements that could be made in the short term and while the user analysis is being conducted. The second step could be implemented over the long term and would be based on the results of the user analysis. Once the results of the user analysis are examined and it has been determined which of the TEHIP databases are most useful to health professionals, then a prioritization of activities (including outreach and training, access, and navigation) should be undertaken around those most useful databases.

The committee recommends that in the short term (during the time that the user analysis is being conducted) NLM continue its efforts to increase access to the TEHIP databases and to simplify navigation of the databases by coordinating the development of the TEHIP Experimental World Wide Web Interface with Internet Grateful Med, promoting online registration for database access, and exploring the possibilities of linking TEHIP's World Wide Web site with the Web sites of other health professional organizations and establishing pointers to the TEHIP databases from World Wide Web search engines.

The committee recommends that in the long term and on the basis of the priorities set as a result of the user analysis, NLM expand its efforts to facilitate access and navigation of the TEHIP databases by making full use of the navigational tools being developed within NLM and beyond. This includes implementation of more efficient and intuitive user interfaces, incorporation of the Unified Medical Language System (UMLS) knowledge sources and other expert systems that would enhance symptom-related and other natural language searches, incorporation of navigational tools and interfaces that would create a seamless interface between databases, and implementation of indicators of peer review into new search interfaces.


As the committee conducted this study, several programmatic issues came to the forefront. It is clear that NLM has taken a great deal of initiative in disseminating toxicology and environmental health information; however, there is a need for a stabilized funding base, an internal commitment to the TEHIP program and involvement of the TEHIP program in broader NLM research and development (R&D) efforts, an interdisciplinary advisory committee, and the development and implementation of a TEHIP-specific evaluation plan. The TEHIP program continues to make a substantial contribution to the fields of toxicology and environmental health, and the beneficial use of toxicology and environmental health information resources by health professionals and other interested user communities can be considerably increased given the necessary resources and support.

The committee recommends that the TEHIP program be given the responsibilities and resources needed to strengthen its growth and development. This may be accomplished by providing a stable funding base, ensuring a leadership role for the TEHIP program and promoting the incorporation of the TEHIP program into broader technological developments at NLM, establishing an interdisciplinary advisory committee, and the implementation of an evaluation plan.


The committee believes that it is important to provide health professionals with the tools needed to retrieve toxicology and environmental health information. During the course of its deliberations, the committee determined that the optimal approach would be to provide health professionals with two different options for accessing toxicology and environmental health information. Primary access would be via an online directory or ''road map" that would assist the user in identifying and connecting with the relevant TEHIP database or other (non-TEHIP) online information resource (e.g., Web sites of government agencies, directory information for environmental health organizations).4 The second access option would be a toll-free telephone number or similar single-access information center that would link health professionals (person-to-person) with a specialist who could provide consultative services on environmental health issues and concerns.

This two-part approach would require cooperative efforts between NLM, other federal agencies, and private-sector organizations. NLM's expertise and current R&D efforts in medical informatics would make it the logical agency to take the leadership role for the online directory, although the assistance of other agencies and organizations would be needed to provide directory information. The development and implementation of the second option, the single-access information center, go beyond NLM's mandate, and this recommendation should be considered by multiple federal agencies and other private-sector organizations involved in environmental health. Public-private partnerships could play a key role in providing these information services. The collaboration of NLM with universities, industry, international resources, and local, state, and federal governments could be particularly productive given the numerous information resources in this field.

The implementation of a single-access information center would have budgetary and interagency ramifications that the committee did not have the mandate to explore. In its exploration of the TEHIP databases and its inquiries into the dissemination of toxicology and environmental health information—especially to health professionals—the committee realized the need for this type of information resource for toxicology and environmental health information. Poison control centers are examples of single-access points that are effectively meeting the information needs of health professionals and other user communities, and the committee believes that poison control centers would make excellent resources for providing toxicology and environmental health information to health professionals. However, the committee is particularly mindful of the budgetary considerations and of the problems that poison control centers would face if their mandate were expanded without the necessary financial resources for implementation. Although the provision of a single-access information center for toxicology and environmental health information is not within the purview of NLM, the issue should be explored because it is important to expanding the use of this information by health professionals.

The committee recommends that NLM, other relevant federal agencies, and private-sector organizations work cooperatively to provide health professionals and other interested user communities with the tools that they need to access toxicology and environmental health information. This would involve two different types of access points:

  • an online directory that would contain information on the full spectrum of information resources in toxicology and environmental health and that would direct the user to the appropriate online information resource; and
  • a single-access information center (e.g., regional poison control centers) that would connect the user with individuals with expertise in environmental health.



The committee's use of the term environmental health includes health issues involving exposures to hazardous substances in the workplace, home, and community settings.


Factors examined in assessing the utility (usefulness) and accessibility (ease of use) of the databases include the subject content, search interface, and available access points.


It is important to note the limitations of the focus groups and questionnaire. The committee did not attempt to obtain a random scientific sample for the distribution of the questionnaire. Rather, the questionnaire was distributed both to professional association members and via the Internet. Thus, it was not feasible to determine the rates of response or to charecterize the nonresponders. Additionally, responding via the Internet requires some degree of computer expertise. Because travel time and expenses were considerations in inviting focus group participants, most of the participants were drawn from the mid-Atlantic, particularly the Washington, D.C. metropolitan area.


The committee's vision of the online directory includes simple interactive screens that walk the user through various options for reaching the appropriate information rerource through hypertext links, graphical interfaces, and search engines.