Every existing chemical database tells you what a substance's current GHS hazard band is. PuroChem tells you what it was, when it changed, what authority reclassified it, and what that change means for your SDS program.
The GHS is not a compendium. It is a living regulatory framework subject to continuous revision — and the revision history is not a footnote. It is the intelligence.
Since the Globally Harmonized System of Classification and Labelling of Chemicals was first adopted by the United Nations in 2003, six major revision cycles have occurred. Each modified classification criteria for multiple hazard classes. In parallel, the EU CLP Regulation's Annex VI — covering mandatory harmonized classifications for approximately 4,000 substances — is updated through ATP processes on a multi-year cycle. IARC Monographs reclassify carcinogens continuously. NTP updates its Report on Carcinogens. OSHA amends the Hazard Communication Standard. Each of these is a potential reclassification event for chemicals in your laboratory.
Under OSHA's Hazard Communication Standard, chemical manufacturers must update Safety Data Sheets within three months of becoming aware of new significant hazard information. Downstream employers — including research laboratories — are expected to maintain current SDS documentation. The problem is that no single source makes it possible to know which chemicals in your inventory have been reclassified since your last review. Until PuroChem, that information simply did not exist in a structured, searchable form.
PuroChem tracks reclassifications across all GHS hazard classes — physical, health, and environmental. Acute toxicity is one of the most frequently reclassified endpoints as new study data becomes available.
The following is an illustrative reclassification history for a hypothetical chemical substance. PuroChem maintains this structured record for approximately 85,000 substances — searchable by chemical, hazard class, authority, date range, and change magnitude.
If this chemical is in your monitored inventory, PuroChem notified your safety team at each of the above events with a structured change summary, the affected GHS hazard classes, and a prioritized SDS review recommendation.
The OSHA Hazard Communication Standard requires a written Chemical Hygiene Plan and a program for maintaining current Safety Data Sheets. What it does not provide is a mechanism for knowing when a chemical in your inventory has been reclassified. PuroChem fills that gap — continuously monitoring the reclassification sources that matter and surfacing changes to the specific chemicals in your inventory before your next OSHA inspection. The longitudinal reclassification history provides the evidence that your program is prospectively maintained, not merely current as of the date it was last audited.
Accessing reliable, structured toxicity data for candidate research chemicals currently requires navigating ECHA, NTP, IRIS, PubChem, and IARC Monographs separately — and none of them tell you how the classification has changed. PuroChem consolidates LD₅₀, NOAEL, IARC group, reproductive toxicity endpoints, and the complete reclassification history in a single structured, citable interface. Understand not only what a compound's current hazard profile is, but whether its classification trajectory suggests emerging regulatory risk that may affect your research program in future grant cycles.
OSHA HazCom program documentation, EPA Tier II threshold quantity screening reports, and institutional EHS annual review packages can all be generated directly from PuroChem's inventory integration. The longitudinal classification history is specifically the kind of evidence that demonstrates to OSHA inspectors that your SDS maintenance program is responsive to new hazard information on an ongoing basis — not simply current as of the date the program was written. Essential for organizations pursuing ISO 14001 or OHSAS 18001 environmental management system certification.
A chemical that has been upgraded from Category 3 to Category 2 to Category 1 across successive GHS revision cycles is not just a currently hazardous compound — it is a compound whose regulatory trajectory signals that future use may become constrained, substitution may become mandatory, or engineering controls may become required. PuroChem enables procurement decisions that account for regulatory trajectory, not only current band. Substitution analysis comparing full GHS profiles of candidate compounds reduces long-term regulatory exposure, not just immediate hazard.
Tell us which chemicals or chemical classes you need coverage for, the regulatory framework you are working under, and how you intend to use the data. We will respond with specifics about database coverage and the most appropriate access tier for your situation.
Alex leads the PuroChem data and methodology team. Questions about database coverage, classification methodology, discrepancy resolution between jurisdictions, or toxicological evidence sourcing go here.
alex_pchem@yashara.usIf a chemical or chemical class you need is not currently in the database, we can prioritize curation on request. Describe the substance (CAS RN or IUPAC name) and the hazard classes you are specifically interested in — carcinogenicity, reproductive toxicity, acute oral toxicity — and we will confirm current depth and expected timeline for full longitudinal history.
The REST API is available for institutional license tiers. If you need programmatic access for integration with an existing EHS management system or chemical inventory platform, mention the system and your preferred integration pattern (REST polling vs. webhook alerts) and we will provide API documentation access.
If you have questions about how we source and validate classification data, how we handle discrepancies between jurisdictional implementations, or how we verify the toxicological evidence behind reclassification events, write directly to Alex's address. These are the questions the team finds most interesting to answer.