This testimony before the Subcommittee on Consumer Protection and Finance concerned the recommending of occupational exposure levels for toxic substances and other activities of NIOSH. In fulfilling the responsibilities given to it, NIOSH has transmitted recommended standards to the Department of Labor concerning 26 substances, including asbestos (1332214), arsenic (7440382), mercury (7439976) and vinyl-chloride (75014). NIOSH annually distributed 20,000 copies of a list of about 17,000 toxic substances with information on their animal lethality, carcinogenic, teratogenic, and mutagenic effects and routes of human exposure. Additional information is being sought on 1500 of these substances which are reported to produce tumors in animals. The Division of Field Studies and Clinical Investigations has undertaken about 35 industrywide studies to determine the long term effects of exposure to low levels of substances, particularly those suspected of causing cancer. Such investigations support the need for pretesting programs that yield experimental evidence of the effects of chemicals on animals prior to commercial production.