TOXNET(TOXicology Data NETwork) is a cluster of databases from NLM covering chemicals and drugs, diseases and the environment, environmental health, occupational safety and health, poisoning, risk assessment and regulations, and toxicology. TOXNET provides free access to several toxicology databases, such as HSDB (Hazardous Substances Data Bank)and TOXMAP, Toxics Release Inventory (TRI), and TOXLINE.