Government
HEW National Toxicology Program on target Program is meeting goals to increase toxicological testing of chemicals and develop testing procedures to meet needs of regulatory agencies Not yet a year old, the Department of Health, Education & Welfare's National Toxicology Program (NTP) appears to be working well. According to its first annual plan, NTP is on its way to meeting its goals of broadening the toxicological characterization of chemicals being tested; increasing the rate of chemical testing, within the limits of available resources; and developing and validating a new series of testing protocols that will meet the regulatory needs of its participating agencies. NTP encompasses the toxicology activities of the Food & Drug Administration, the National Cancer Institute, National Institute of Environmental Health Sciences, and the National Institute for Occupational Safety & Health. Its fiscal 1979 budget of $260 million provided about $70 million for basic research, $71 million for testing, and $19 million for methods development. The program is under the direction of David Rail, who is also the head of NIEHS. In announcing the annual plan, he characterized NTP as "one of the most exciting developments in the field of toxicology." He admits that "the problems of chemicals in our environment and their potential for adversely affecting human health are so vast and so important that the government alone cannot solve the problem." But he says that NTP does provide an effective organizational framework within which the federal health-related research and regulatory agencies can work together as has not been possible in the past. The program's most important function is consolidating and coordinating a number of activities, such as selecting chemicals to be tested, data management and analysis, and laboratory animal production and quality control, that used to be carried out separately by the agencies involved.
Rail: NTP provides effective framework
In its first year NTP has assumed responsibility for 147 chemicals already being tested by the four agencies for carcinogenic potential in lifetime rodent bioassays. An additional 106 chemicals have been selected for extensive toxicological and carcinogenic testing. Testing on 60 of the chemicals commenced this year and testing of the rest is scheduled to begin in fiscal 1980. In addition, the nomination of 104 other chemicals for testing will be evaluated. NTP is giving high priority, it says, to establishing a process for scientific review of the adequacy of the test data it develops. It is also developing a set of principles for selecting chemicals for testing that takes into account such factors as the extent and intensity of human exposure, severity of toxicological effects, and the scientific need to compare testing methodologies and/or study structure-activity relationships. Selection of a chemical does not commit it to testing a priori, NTP says. What it does is commit NTP to ascertain the specific toxicological and regulatory concerns about the chemical, evaluate the adequacy of existing data, and then propose and conduct the specific tests that are needed, if any. In addition to selecting chemicals to be tested, NTP is also developing and validating new test methods. For instance, in the area of teratogenesis,
NTP points out that in recent years experiments have clearly shown that functional abnormalities, without gross malformations, can result from chemical exposure during development, behavioral abnormalities being the principal example. Several foreign countries have recently imposed general requirements for behavioral teratology, NTP says, and the Toxic Substances Control Act also may mandate such testing. Therefore, NTP says it is imperative that the validity of behavioral teratology test procedures be established. To do so, NTP is proposing that four to six test methods, which appear to have the greatest potential utility, will be used in six laboratories using standard chemicals. Recommendations concerning the incorporation of behavioral teratology methods into reproduction and teratology testing guidelines should then be possible, based on the result of these studies, NTP says. The project will take two to three years to complete. In the area of mutagenesis testing, NTP's major goal is to establish a battery of procedures that, when used as a prescreen, can aid in establishing priorities for in-depth animal studies. Thus, it is directing its efforts toward development, definition, and standardization of methods for routine testing; determination of the intraand interlaboratory reproducibility of defined protocols; and evaluation of tests using coded chemicals and representing different chemical classes of known mutagenic activity. The most complex and highest priority need in the data management and analysis area, according to the plan, is management of lifetime bioassays. Current systems lack an automated data input system and quality control features at the testing laboratory. NTP has selected a modular computer system, the Toxicology Data Management System, for continued prototype development and on-line installation at three laboratory facilities in early 1980, with additional installation projected for later in the year. NTP also is giving high priority to early development of a simple system to provide on-line information on chemicals selected for testing, the nature of the test(s), and test status. D Sept. 3, 1979 C&EN
21
