Toxnet consists of the following nine databases:

HSDB hazardous substances database. Broad scope in human and animal toxicity, safety and handling, environmental fate, and more. Scientifically peer-reviewed.
IRIS Integrated Risk Information System - data from the EPA in support of human health risk assessment, focusing on hazard identification and dose-response assessment.
ITER A product of the Cincinnati based Toxicology Excellence for Risk Assessment, ITER presents chemical risk information from authoritative groups worldwide, including the U.S. Environmental Protection Agency, the U.S. Agency for Toxic Substances and Disease Registry, Health Canada, the Dutch National Institute of Public Health and the Environment, the International Agency for Research on Cancer, as well as independent parties whose risk values have undergone peer review.
GENE-TOX Peer-reviewed mutagenicity test data from the Environmental Protection Agency (EPA).
CCRIS Chemical Carcinogenesis Research Information System - carcinogenicity, mutagenicity, tumor promotion, and tumor inhibition data provided by the National Cancer Institute (NCI).
TOXLINE Extensive array of references to literature on biochemical, pharmacological, physiological, and toxicological effects of drugs and other chemicals.
DART/ETIC Developmental and Reproductive Toxicology and Environmental Teratology Information Center - Current and older literature on developmental and reproductive toxicology.
TRI Annual estimated releases of toxic chemicals to the environment - the Environmental Protection Agency's TRI (Toxics Release Inventory) - reporting years 1995 - 2000.
ChemIDplus Numerous chemical synonyms, structures, regulatory list information, and links to other databases containing information about the chemicals.