HSDB, the Hazardous Substances Data Bank, and where it is now
HSDB was the US NLM's peer-reviewed toxicology database on 5,000+ chemicals. TOXNET closed in December 2019 and HSDB records are now in PubChem.
HSDB and the Hazardous Substances Data Bank in PubChem
HSDB, the Hazardous Substances Data Bank, was the US National Library of Medicine's peer-reviewed toxicology database on over 5,000 substances. NLM retired TOXNET on 16 December 2019 and moved HSDB into PubChem. You can still open the records, but don't treat an exposure limit or regulatory line in them as current law.
What was in the HSDB database
HSDB was one of the primary databases in NLM's TOXNET system. Records held excerpts from the published literature on human health effects, exposure, emergency medical treatment, standards and regulations, safety and handling, and environmental fate. NLM referenced and derived that data from books, government documents, technical reports, selected primary journal literature and electronic sources, including IARC, WHO and ACGIH (NLM Technical Bulletin, 2007).
Records were split into 15 categories with over 150 fields. They included human health effects, emergency medical treatment, animal toxicity studies, metabolism and pharmacokinetics, environmental fate, occupational exposure standards, safety and handling, and manufacturing and use. A Scientific Review Panel of experts in the database's subject areas reviewed the content. Each record's administrative section listed the last revision date, the last review date and the update history (NLM, 2007). NLM's data.gov entry still says a Scientific Review Panel assessed the information.
Why TOXNET was retired in 2019
On 24 September 2019, NLM announced that the TOXNET website would be retired on 16 December 2019 (NLM, 2019). The old address, toxnet.nlm.nih.gov, no longer serves the databases. The most frequently used databases went into PubChem, PubMed and Bookshelf. Some databases were retired.
NLM's stated reason is one sentence: "As part of a broader NLM reorganization, most of NLM's toxicology information services have been integrated into other NLM products and services" (TOXNET has moved). Under its Strategic Plan 2017-2027, NLM closed the Specialized Information Services division, which ran TOXNET, effective 30 June 2019. An editor's note on that bulletin says SIS was retired on 16 December 2019 (NLM, 2019).
Where the TOXNET databases went
If an old TOXNET link is dead, NLM's migration notice and transition page put the main databases here.
| TOXNET database | Where it is now |
|---|---|
| HSDB | PubChem, plus a data download |
| CCRIS, GENE-TOX | PubChem, archived and no longer updated |
| ChemIDplus | PubChem (standalone site retired December 2022) |
| LactMed (Drugs and Lactation Database) | NCBI Bookshelf |
| LiverTox | NCBI Bookshelf |
| TOXLINE | Data download only |
| IRIS, TRI | US EPA |
| TOXMAP | Retired; data via EPA geospatial resources |
| CTD (Comparative Toxicogenomics Database) | NC State University |
| Haz-Map | Haz-Map.com |
| HPD (Household Products Safety Database) | Consumer Product Information Database |
| ITER (International Toxicity Estimates for Risk) | Some content at Toxicology Excellence for Risk Assessment (TERA) |
| CPDB (Carcinogenic Potency Database) | Retired; download from NLM Data Discovery |
For breastfeeding questions that used to start at TOXNET LactMed, open the LactMed page on Bookshelf. NLM said it "will continue to be updated there" (NLM, 2019). The migration notice says the LactMed mobile apps are no longer being updated.
TOXLINE is now a data download only. NLM removed the PubMed toxicology subset in early December 2021, kept the last version of the query as a search strategy, and said those selected queries are no longer updated (NLM, 2021). ChemIDplus stayed up after TOXNET closed. NLM retired the standalone site on 12 December 2022 and made PubChem its single source for chemical information (NLM, 2022).
How to find an HSDB record in PubChem
NLM's how-to page gives these steps:
- Search PubChem by chemical name, molecular formula, CAS RN, SMILES, or InChI.
- Select the "Best Match" compound.
- HSDB text is spread through the compound page. Expand the sections, then use Ctrl+F for a field name.
- For HSDB-only content, scroll to the last section, "Information Sources", expand "FILTER BY SOURCE", and select HSDB under the TOXNET sources.
If the citation gives an HSDB number, there's a shorter path. Put the number on the end of pubchem.ncbi.nlm.nih.gov/source/hsdb/. Benzene is HSDB 35 at pubchem.ncbi.nlm.nih.gov/source/hsdb/35. Use that style of URL when you replace a dead toxnet.nlm.nih.gov link in an SDS or a dossier.
PubChem lists HSDB as data source 11933, from NLM, with 6,060 annotations. Annotations are PubChem's unit, not a count of chemicals. The source table showed Last Updated 2026/07/10 on 14 October 2026. That date reflects PubChem processing, not a revision of the scientific content.
For bulk work, NLM offers a download of "over 5,000 hazardous substance records" from data.gov. That page says this subset "is no longer updated." NLM Data Discovery holds a 2015-2019 subset "for research and historical relevance."
Using HSDB data in 2026
On the original records, the administrative section held the last revision and review dates (NLM, 2007). Look for those dates on the PubChem record before you quote a number. Before an HSDB value goes into an SDS or a submission, check it with the regulator or body that sets it.
RegAffairs AI's cited answer on HSDB links to the records' current locations and NLM's archived downloads.