Acute Toxicity Database
   Statistical approaches for taxonomic comparisons, and factors such as age, pH, temperature, water hardness, and diet affecting toxicological outcome. Maintained by the Columbia Environmental Research Center, Missouri.
   http://www.cerc.cr.usgs.gov/data/acute/acute.html

Distributed Structure-Searchable Toxicity Database Network
   DSSTox provides a community forum for publishing standard format, structure-annotated toxicity data files for open public access. Offers search based on chemical formula, maintained by the Environment Protection Agency, USA.
   http://www.epa.gov/nheerl/dsstox/

Tetratox
   Database of toxic potency data for more than 2,100 industrial organic compounds maintained by the College of Veterinary Medicine, University of Tennessee, Knoxville.
   http://www.vet.utk.edu/TETRATOX/

Toxicology and Environmental Health Information
   Databases and resources related to toxicity, hazardous chemicals and ecological hazards, at National Library of Medicine, Bethesda, Maryland.
   http://www.sis.nlm.nih.gov/Tox/ToxMain.html

Toxicology sites
   Toxicology sites maintained by Dr. Hardin, at University of Iowa.
   http://www.lib.uiowa.edu/hardin/md/tox.html