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Fact Sheet
TOXNET®: Toxicology Data Network

TOXNET (TOXicology Data NETwork) is a cluster of databases covering toxicology, hazardous chemicals, environmental health and related areas. It is managed by the Toxicology and Environmental Health Information Program (TEHIP) in the Division of Specialized Information Services (SIS) of the National Library of Medicine (NLM). TOXNET provides free access to and easy searching of the following databases:

Toxicology Databases

HSDB® (Hazardous Substances Data Bank)
A factual database focusing on the toxicology of over 5,000 potentially hazardous chemicals. In addition to toxicity data, HSDB provides information in the areas of emergency handling procedures, industrial hygiene, environmental fate, human exposure, detection methods, and regulatory requirements. The data are fully referenced and peer-reviewed by a Scientific Review Panel composed of expert scientists.
IRIS (Integrated Risk Information System)
A database from the U.S. Environmental Protection Agency (EPA) containing carcinogenic and non-carcinogenic health risk information on over 500 chemicals. IRIS risk assessment data has been scientifically reviewed by EPA scientists and represents EPA consensus.
ITER (International Toxicity Estimates for Risk)
This database contains data in support of human health risk assessments. It is compiled by Toxicology Excellence for Risk Assessment (TERA) and contains over 650 chemical records. ITER provides a comparison of international risk assessment information in a side-by-side format and explains differences in risk values derived by different organizations. ITER data, focusing on hazard identification and dose-response assessment, is extracted from each agency’s assessment and contains links to the source documentation.
CCRIS (Chemical Carcinogenesis Research Information System).
A scientifically evaluated and fully referenced data bank, developed and maintained by the National Cancer Institute (NCI). It contains over 9,000 chemical records with carcinogenicity, mutagenicity, tumor promotion, and tumor inhibition test results. Data are derived from studies cited in primary journals, current awareness tools, NCI reports, and other special sources. Test results have been reviewed by experts in carcinogenesis and mutagenesis.
GENE-TOX (Genetic Toxicology)
A toxicology database created by the U.S. Environmental Protection Agency (EPA) containing genetic toxicology test results on over 3,200 chemicals. Selected literature was reviewed by scientific experts for each of the test systems under evaluation; the results are represented in GENE-TOX.
Tox Town®
An interactive guide to commonly encountered toxic substances, your health, and the environment. It uses color, graphics, sounds and animation to convey connections between chemicals, the environment, and the public's health. The Town, City, Farm, U.S. Mexico Border and Port are designed to provide facts on toxic chemicals found in everyday locations, information about how the environment can impact human health, non-technical descriptions of chemicals, links to authoritative chemical information on the Internet, and Internet resources on environmental health topics. Tox Town's target audience is students above elementary-school level, educators, and the general public. It is a companion to the extensive information in the TOXNET collection of databases that are typically used by toxicologists and health professionals. Tox Town also offers some resources in Spanish (
Household Products Database
This database provides information on the potential health effects of chemicals contained in more than 7,000 common household products used inside and around the home. The database allows users to browse a product category, such as 'Pesticides' or 'Personal Care,' by alphabetical listing of brand names. Products can also be searched by type, manufacturer, product ingredient/chemical name and by health effects. The record for each product shows the ingredients as reported in the manufacturer's Material Safety Data Sheet (MSDS) and includes other information such as handling, disposal, and health effects.
An occupational toxicology database designed primarily for health and safety professionals, but also for consumers seeking information about the health effects of exposure to chemicals and biologicals at work. It links jobs and hazardous tasks with occupational diseases and their symptoms. The 1,595 chemicals and biological agents in the database are related to industrial processes and other activities such as hobbies. The linkage indicates the potential for exposure to the agents. The 224 occupational diseases and their symptoms are associated with hazardous job tasks. This association indicates an increased risk for significant exposure and subsequent disease.
A web site from the National Library of Medicine (NLM) that uses maps of the United States to show the amount and location of toxic chemicals released into the environment. Data is derived from the EPA's Toxics Release Inventory (TRI), which provides information on the releases of toxic chemicals into the environment as reported annually by industrial facilities around the United States.
LactMed (Drugs and Lactation)
A database of drugs and other chemicals to which breastfeeding mothers may be exposed. It includes information on the levels of such substances in breast milk and infant blood, and the possible adverse effects in the nursing infant. Statements of the American Academy of Pediatrics concerning a drug’s compatibility with breastfeeding are provided, as are suggested therapeutic alternatives to those drugs where appropriate. All data are derived from the scientific literature and fully referenced.
CPDB (Carcinogenic Potency Database)
This database was developed at the University of California, Berkeley, and Lawrence Berkeley Laboratory. It provides standardized analyses of the results of 6540 chronic, long-term animal cancer tests that have been conducted since the 1950's and reported in the general published literature or by the National Cancer Institute and the National Toxicology Program.

The TOXNET "Multiple Databases" option allows for simultaneous searching of HSDB, IRIS, CCRIS, and GENE-TOX.

Toxicology Literature

A bibliographic database providing comprehensive coverage of the biochemical, pharmacological, physiological, and toxicological effects of drugs and other chemicals from 1965 to the present. TOXLINE contains over 3 million citations, almost all with abstracts and/or index terms and CAS Registry Numbers.
DART®/ETIC (Development and Reproductive Toxicology/Environmental Teratology Information Center)
A bibliographic database covering literature on reproductive and developmental toxicology. DART is managed by NLM and funded by the EPA, the National Institute of Environmental Health Sciences (NIEHS) and NLM. DART/ETIC contains references to reproductive and developmental toxicology literature published since 1965.
Toxics Release Inventory (TRI)
A series of databases that describe the releases of toxic chemicals into the environment annually for the 1987-2006 reporting years. TRI is mandated by the Emergency Planning and Community Right-to-Know Act and is based on data submitted to the EPA from industrial facilities throughout the U.S. These data include the names and addresses of those facilities, and the amounts of certain toxic chemicals they release to the air, water, or land, or transfer to waste sites. Information is included on over 650 chemicals and chemical categories. Pollution prevention data are also reported by each facility for each chemical. There were two changes to reporting requirements for the 2006 data. Facilities were required to submit appropriate North American Industry Classification System (NAICS) codes rather than the Standard Industrial Classification (SIC) codes previously used. To do trends analysis, EPA assigned NAICS codes to prior years’ data, so now both SIC codes and NAICS codes are searchable on TOXNET. EPA also expanded Form A eligibility to include PBT chemicals in 2006.

Chemical Information

A database providing access to structure and nomenclature authority databases used for the identification of chemical substances cited in NLM databases. ChemIDplus contains over 380,000 chemical records, of which over 289,000 include chemical structures. ChemIDplus is searchable by Name, Synonym, CAS Registry Number, Molecular Formula, Classification Code, Locator Code, Structure, and/or Physical properties. Enhanced structure display is available in ChemIDplus Advanced.

Web Access/Searching

TOXNET databases are accessible free of charge at:

TOXNET's web interface is designed as an easy way to search databases of varying formats and content. It can be used to locate toxicology data, literature references, and toxic release information on particular chemicals as well as to search to identify chemicals that cause specific effects. TOXNET offers a variety of ways to display and sort information. Its "Multi-Databases" feature provides an integrated search of any or all of several databases (HSDB, IRIS, CCRIS, GENE-TOX, ITER, LactMed). Its "Search All Databases" feature provides a list of TOXNET databases in which a search term is found, each paired with the retrieval record count and with links to the Search Results page of those databases.

Links are available from TOXNET to PubMed®, NLM's free web interface to the world's biomedical literature, and to additional sources of toxicological information.

Further Information

For detailed information on TOXNET, contact:

Specialized Information Services
National Library of Medicine
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6707 Democracy Boulevard, MSC 5467
Bethesda, MD 20892-5467
Telephone: (301) 496-1131

For general information on the Library's computerized information services, including TOXNET, contact:

National Library of Medicine
Customer Service
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Bethesda, MD 20894
Telephone: 1-888-FINDNLM (1-888-346-3656)

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Last reviewed: 15 April 2008
Last updated: 15 April 2008
First published: 22 February 2005
Metadata| Permanence level: Permanent: Stable Content
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