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Dr. HOEL. I think the most important thing we have started, which we had not done in the past, is to form a group of experts to concentrate on a particular area. We are starting with agricultural chemicals to see which ones they believe to be of the greatest importance from a public health standpoint with regard to toxicological testing-what types of tests and so on. They can advise us as to what the priorities should be.

Then the second issue would be what are we doing in terms of the toxicity testing. It is a long process

in terms of nomination and going through preliminary research and testing. In 1991, among our subchronic tests we are beginning 21, of which 3 are agricultural chemicals, and of the chronic tests, we are beginning, 13, of which 1 is agricultural. In 1992, of our subchronics, we will begin 14, of which 4 are agricultural, and of the chronics, 2 of the 12 are agricultural.

We have many competing issues here. For example, research on electromagnetic fields will begin. The retroviral vector that was mentioned relative to gene therapy will be tested. And so, there are quite a few other competing issues.

QUESTIONS SUBMITTED BY THE SUBCOMMITTEE Senator HARKIN. Thank you very much, Dr. Hoel. There will be some additional questions which will be submitted for your response in the record.

(The following questions were not asked at the hearing, þut were submitted to the Institute for response subsequent to the hearing:)



Question. The Clean Air act Amendments which passed last October placed a number of requirements on your Institute to perform air pollution studies. More specifically, the studies are to identify the critical toxic elements in the air and the level at which they become health hazards. These additional responsibilities I understand would cost your Institute approximately $8 million.

Why is there no request for these funds ?

Answer. When the Clean Air Act Amendments were signed into law on November 15, 1990, the process of preparation of the budget request for NIEHS for fiscal year 1992 was too far along to permit the major revisions and recalculations needed to justify additional funds to support a major expansion of research into the health effects of air toxics. However, our internal planning process tracked the progress of the Clean Air Act Amendments relating to health effects research over the summer of 1990 in anticipation of passage and enactment. We have completed a research plan which describes and sets priorities for additional studies authorized in the new law including biomedical, epidemiologic, and toxicologic studies intended to characterize the health risks of the air toxics cited in the 'reauthorization.


Question. Last year, the Committee raised a concern that your National Toxicology Program (NTP) has developed a number of non-animal methods, or tests, that could be used for examining the health effects of chemical compounds but funding has been too short to validate these tests. In fact, the budget of the portion of the National Toxicology Program which validates nonanimal tests dropped from $5.7 million in 1984 to $2.8 million in 1990. I see you are requesting $3.9 million for this program in 1992. What can you tell the Committee about your efforts to validate these non-animal tests?

Answer. Since NTP's establishment, it has given high priority to development and validation of toxicologic assay methods which may reduce the use of whole animals and/or provide other non-animal models in toxicologic studies. One of our major efforts has been in the extensive validation of short-term mutagenicity studies. We have learned that a small battery of assays, including the bacterial Salmonella assay, identifies mutagenic activity and that a positive in-vitro mutagenicity result is a clear signal that a chemical is 11kely to be carcinogenic in animals. A negative mutagenicity result, however, is unclear regarding carcinogenicity. The demonstration that the existing short-term methods were severely limited for identifying carcinogens dictated that we explore methods that reduce our dependence on animals. New efforts will be directed to specific projects thať utilize computer-assisted chemical analysis and the latest methods of gene manipulation to develop non-animal models.

Question. To what extent will the validation of these tests help reduce the use of animals in your research?

Answer. One effort to reduce the use of animals in research is in the area of computer-assisted chemical analysis of the diverse chemical classes that have been assayed for cancer and other toxic endpoints. If such information proves diagnostic, it could be used to reduce the necessity to test additional chemicals within a given class, thereby reducing numbers of animal studies needed. Another major effort enables researchers to transfer and direct the expression of genes into cells. As knowledge of molecular aspects of cancer improves, it becomes increasingly possible to introduce and activate metabolically important genes in cultured cells so that individual cells can assume many of the functions found in intact tissues in animals. Among the

advantages of these cells would be their ability to activate and detoxify chemical substances and their ability to exhibit easily measurable biochemical responses. While these efforts should reduce our dependence on animals, there is considerable scientific doubt about the prospects for total replacement of mammalian systems for toxicologic studies in the foreseeable future.


Question. Last year the Committee expressed concern about the health effects of constant exposure to low radiation emitting from such sources as electric blankets and power lines. Tell us the progress you are making on the research in this area and how it is coordinated with work funded by the Environmental Protection Agency.

Answer. The NIEHS has a number of activities which address the concerns raised about the health effects of low frequency electromagnetic fields (EMF) emitted by sources such as power lines. In September 1990, the Institute held a planning conference with participation by the Environmental Protection Agency (EPA), the National Institute of Child Health and Human Development, the National Institute for Neurologic Disorders and Stroke, the Electric Power Research Institute, and selected principal Investigators. This meeting provided a direction for a program announcement planned for May 1991. The focus of this announcement is on the biological effects and basic mechanisms of low frequency EMF. In addition, this announcement encourages , investigators to develop improved exposure systems for EMF studies.

In February of this year, the NIEHS hosted a workshop entitled "Recent Developments on the Health Consequences and clinical Applications of Low Frequency Electromagnetic Fields." This workshop helped to provide an awareness of the methodological problems encountered in conducting studies on EMF health effects, and provided an overview of the status of EMF research.

In FY 1991 the NIEHS funded three new grants on EMF health effects. Two of the grants are examining the effects of EMF at the cellular level, and the other grant is developing methodologies for precisely measuring exposures to low frequency radiation.

The NTP has been requested by the Department of Energy (DOE), the National Association of Regulatory Utility Commissioners, and the utilities Industries to evaluate the toxic and carcinogenic potential of EMF in laboratory animals. The nomination was approved by the NTP Executive Committee which is comprised of nine Federal Agency Heads including the Administrator, EPA. The study design has been reviewed and approved by many expert scientists, including those from the EPA. No comparable studies have been planned by the EPA, DOE, or other Federal agencies. The first studies on the reproductive effects and possible carcinogenicity of 60 Hz magnetic fields will begin this year.


Question. For a number of years the Committee has been aware of your Institute's interest in constructing a new building to replace your North Campus building in Research Triangle Park. I understand the lease on your existing building expires in May and that you are anticipating the costs of improvement for safety and air handling plus inflation will increase the rental costs by up to 50 percent at renewal time. This seems to make the option of building even more cost effective.

We have already paid for the architectural and engineering work of the new building, which I believe was finished last November. What is the shelf life of this work?

Answer. The plans that we now have will be good until July 1992. If we haven't received a building permit by that time we would have to update the design to meet new building code requirements at a cost of approximately $1 million.



Question. Dr. Hoel, earlier today I raised a question with Dr. Broder regarding the health effects of electromagnetic fields. As you may have heard, the residents of South Scranton are deeply concerned over the high voltage power lines which run through their community, and reports of an elevated incidence of cancer. Has the Institute supported studies on this matter?

Answer. Yes, the Institute began several projects in FY 1991 which address the concerns raised about the health effects of low frequency electromagnetic fields (EMF) emitted by sources such as power lines. Three new grants were funded which deal with the effects of EMF at the cellular level and with developing methodologies for precisely measuring exposures to low frequency radiation. NIEHS' National Toxicology Program (NTP) has begun studies on the reproductive effects and possible carcinogenicity of 60 Hz magnetic fields,

Question. Should a health effects study be done and what role could the National Institute of Environmental Health Sciences play in the matter?

Answer. Health effects studies should certainly be done. The Institute held a planning conference in September 1990 with participation by the Environmental Protection Agency, the National Institute of Child Health and Human Development, the National Institute for Neurologic Disorders and Stroke, the Electric Power Research Institute, and selected principal investigators. The focus of the conference was on the biological effects and basic mechanisms of low frequency EMF. Also, the Department of Energy, the National Association of Regulatory Utility Commissions, and the utilities industries have requested the NTP to evaluate the toxic and carcinogenic potential of EMF in laboratory animals,



BUDGET REQUEST Senator HARKIN. Dr. Schambra, the committee has your request of $19.9 million, which is $13.7 million more than last year.

We are familiar with your programs to support visits of foreign scientists to the United States and the placement of U.S. scientists overseas. The committee looks forward to hearing about your expanding Eastern European and Latin American initiatives.

Welcome and please proceed with your statement.
Dr. SCHAMBRA. Thank you, Senator.

Senator, I will be even briefer than the prepared summary of my opening statement, both of which I would like to submit for the record with your permission.

Senator HARKIN. Certainly.

Dr. SCHAMBRA. Mr. Chairman, I think it is clear that we live in a time of enormous changes and of enormous challenges and opportunities. The countries of central and Eastern Europe and the Soviet Union have opened up and our scientists have responded. We have much to give and much to learn in the exchanges which are taking place and growing day by day aided by our Eastern European initiative which the Congress has so strongly supported. I would be pleased to tell you more about what we are doing under that initiative later on in response to a question or for the record, if you wish.

Likewise, the importance of collaborating with scientists and institutions in developing countries is becoming increasingly clear. Not only must these countries deal with old, unconquered diseases such as malaria and cholera—and as you know from the papers right now, cholera is killing hundreds of people in South America even today—but also the poorer regions of the world are often the source of new diseases such as AIDS which threaten the entire world.

AIDS TRAINING PROGRAM Our international AIDS training programs, now in their third year, constitute one of the most important responses by the U.S. Government to addressing the AIDS problem by helping developing countries participate in research on this disease and eventually participate in the field trials of vaccines now under development in the NIH and elsewhere.

Because of the threat which diseases in developing countries represent not only to the people of these countries, but also to the people of the United States, we began our Latin American initiative last year to expand cooperation between biomedical scientists of

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