TSCATS (Toxic Substances Control Act Test Submissions) is an online index to unpublished, nonconfidential studies covering chemical testing results and adverse effects of chemicals on health and ecological systems. The studies are submitted by U.S. industry to EPA under several sections of the Toxic Substances Control Act (TSCA). There are four types of documents in the database: Section 4 chemical testing results, Section 8(d) health and safety studies, Section 8(e) substantial risk of injury to health or the environment notices, and voluntary documents submitted to EPA known as a For Your Information (FYI) notice. TSCATS contains information that is pertinent to the risk assessment and hazard evaluation processes. The information can be used in conjunction with published material and is a valuable source along with or in the absence of published data. The data are used by federal and state agencies, researchers, toxicologists, risk assessors, the regulated industry, attorneys, trade and professional associations. TSCATS was developed to make ongoing and completed chemical testing studies available to the public and includes chemical exposure studies, epidemiology, environmental fate, monitoring, episodic incidents, such as spills and case reports. There are 81,000 studies on 6,700 unique chemical substances are contained in 23,000 documents. On average three or four individual studies are extracted from each document. Studies are indexed under three broad categories: health effects, ecological effects and environmental fate. Additional controlled vocabulary terms are assigned to describe the experimental protocol and test observations. A TSCATS record also includes: the chemical name, CAS (Chemical Abstracts Service) Registry Number, Section of TSCA, title, document number, microfiche number, submitting organization, and performing organization. A select number of studies also have abstracts. Microfiche copies of the full-text documents of the unpublished reports referenced by TSCATS are directly available from NTIS. The titles of these 23,000 unpublished reports can be searched directly on the NTIS web site at www.ntis.gov/yellowbk/1nty834.htm.