CompTox Chemicals Dashboard: EPA Data Guide

The Computational Toxicology (CompTox) Chemicals Dashboard is a publicly accessible web platform developed by the United States Environmental Protection Agency (EPA) to evaluate the hazard profiles, physicochemical properties, and environmental fate of chemicals. Formerly known as the Chemistry Dashboard, the platform integrates empirical measurements, predictive models, and high-throughput screening data into a standardized resource for toxicologists, exposure scientists, and environmental health researchers. It provides structured access to chemical structures, regulatory lists, in vivo hazard points of departure, and in vitro bioactivity screening metrics.

In modern chemical hazard assessment and environmental testing laboratories, computational tools serve as an essential screening tier alongside analytical chemistry workflows. Facilities conducting laboratory environmental monitoring or tracking chemical residues rely on centralized databases to associate observed structures with established toxicity thresholds and regulatory hazard listings. The CompTox Chemicals Dashboard integrates predictive quantitative structure-activity relationship (QSAR) models with analytical standards, allowing research teams to evaluate emerging contaminants, prioritize testing candidates, and assess structural analogues without unnecessary animal testing.

What It Is

The CompTox Chemicals Dashboard is the centralized discovery platform for the EPA Center for Computational Toxicology and Exposure (CCTE). The dashboard addresses the data gap between the hundreds of thousands of commercial chemicals in use and the traditional in vivo toxicological datasets that exist for only a fraction of them. It aggregates empirical measurements and predicted values from EPA research programs, federal partners, international regulatory bodies, and public repositories.

At the structural core of the dashboard is the Distributed Structure-Searchable Toxicity (DSSTox) Database. DSSTox enforces rigorous curation by mapping substance names and Chemical Abstracts Service Registry Numbers (CASRN) to validated structural representations, InChIKeys, and DSSTox Substance Identifiers (DTXSID). This standard allows researchers to query compounds by exact structure, substructure, or structural similarity using Tanimoto metrics, linking chemical identity directly with biological activity.

Who Runs It and What It Covers

The CompTox Chemicals Dashboard is operated and maintained by the EPA Office of Research and Development (ORD) through its Center for Computational Toxicology and Exposure. As of the August 2026 release, the platform indexes 1,386,492 chemical substances and maintains over 300 curated chemical lists grouped by regulatory interest, structural class, and industrial use.

The platform covers several primary domains:

• Substance Identification: Curated mappings between DTXSID, CASRN, IUPAC names, synonyms, molecular formulas, mass, and SMILES strings.
• Physicochemical Properties: Experimental values alongside consensus predictions from the Open Structure-activity Relationship App (OPERA) and the Toxicity Estimation Software Tool (TEST) for boiling points, logP, vapor pressure, and water solubility.
• Environmental Fate and Transport: Parameters covering atmospheric degradation, bioconcentration factors, soil sorption (Koc), and biodegradation rates.
• Hazard and In Vivo Toxicity: Points of departure (POD), reference doses (RfD), and reference concentrations (RfC) from EPA Integrated Risk Information System (IRIS) assessments, Provisional Peer-Reviewed Toxicity Values (PPRTV), and regulatory dossiers.
• In Vitro Bioactivity: Quantitative high-throughput screening results from ToxCast and Tox21 initiatives, cataloging concentration-response curves across hundreds of biological assays and gene targets.
• Exposure and Product Usage: Consumer product composition data, functional use categories, and manufacturing volumes from the Chemical and Products Database (CPDat) and ChemExpo.

How to Search or Use It

Navigating the CompTox Chemicals Dashboard follows structured search workflows. When establishing a sample chain of custody or screening unidentified peaks from non-targeted mass spectrometry, researchers use the following steps:

1. Select the Search Mode: Open the dashboard homepage and choose Basic Search (for individual compounds), Batch Search (for multi-analyte processing), Product/Use Categories, or Assay/Gene querying.
2. Enter Chemical Identifiers: In Basic Search, input a chemical name, CASRN, DTXSID, or InChIKey skeleton into the search bar. Alternatively, enter a Mass Spectrometry (MS) Ready monoisotopic mass with a defined tolerance window (e.g., ±5 ppm) for non-targeted identification.
3. Select the Matched Substance: Review the auto-suggest dropdown list and select the confirmed substance to load the chemical summary overview.
4. Review Identity on the Details Tab: Inspect the Details tab to verify molecular formulas, average mass, DSSTox curation quality flags, and memberships in curated lists such as federal drinking water standards or PFAS monitor lists.
5. Evaluate Measured and Predicted Properties: Navigate to the Properties and Environmental Fate/Transport tabs to examine physicochemical parameters, comparing experimental values against OPERA and TEST predictions.
6. Screen Bioactivity Endpoints: Check the Executive Summary for an at-a-glance profile of data completeness, then open the Bioactivity tab to examine ToxCast concentration-response curves and active assay targets across cellular pathways.
7. Execute Batch Downloads: When evaluating multi-analyte panels (up to 10,000 substances), open Batch Search, paste your identifier list, select the required output fields, and export data in CSV, Excel, or SDF format.

Strengths and Limits

The CompTox Chemicals Dashboard provides distinct advantages for toxicologists and analytical chemists:

• Centralized Data Integration: Unifies physical properties, bioassays, and exposure estimates into a single open-access interface, eliminating manual aggregation across fragmented agency databases.
• Transparent Modeling: Distinguishes measured values from QSAR computational estimates and provides QSAR Model Reporting Format (QMRF) documentation.
• High-Throughput Screening Depth: Direct access to complete ToxCast and Tox21 in vitro bioactivity data provides biological context prior to animal testing.
• Scalable Batch Export: Enables automated processing of up to 10,000 chemical identifiers simultaneously in standardized structural and tabular formats.

Researchers must also account for practical platform limits:

• Model Applicability Domains: Predicted endpoints derived from QSAR algorithms depend on training set chemistry; highly unusual novel structures may fall outside reliable model bounds.
• Variable In Vivo Coverage: While indexing exceeds 1.3 million chemicals, comprehensive in vivo toxicological studies and definitive hazard thresholds exist for only prioritized commercial subsets.
• Versioned Release Cycles: Updates occur periodically; research teams must document specific data release dates when preparing regulatory submissions.

Alternatives

Depending on analytical requirements, researchers cross-reference the CompTox Chemicals Dashboard with alternative chemical repositories, including an organic spectroscopy database or international hazard registries. The table below summarizes key differences.

Platform	Operating Institution	Primary Scope	Chemical Identifiers Used	Key Strengths
CompTox Chemicals Dashboard	US EPA (CCTE / ORD)	Environmental toxicology, high-throughput screening, and predictive exposure	DTXSID, CASRN, InChIKey	ToxCast bioassay integration, OPERA QSAR models, batch search up to 10,000 terms
PubChem	NIH / NLM (NCBI)	Broad biomedical chemistry, bioassays, and patent literature	CID, SID, InChIKey	Massive scale (110M+ compounds), extensive bioactivity data, robust PUG-REST API
ECOTOX Knowledgebase	US EPA (ORD)	Ecological toxicity endpoints for aquatic and terrestrial wildlife species	CASRN, Chemical Name	Single-chemical in vivo laboratory and field ecotoxicology test records
ECHA REACH Dossiers	European Chemicals Agency	European regulatory compliance, industrial chemical registration dossiers	EC Number, CASRN	Legally mandated industrial safety registrations and European risk assessments
eChemPortal	OECD	Global government hazard and exposure data aggregation	CASRN, Chemical Name	International regulatory harmonization linking multiple national chemical inventories

FAQ

What is the difference between a DTXSID and a CASRN in the CompTox Dashboard?

A CASRN (Chemical Abstracts Service Registry Number) is an internationally recognized identifier for chemical substances. A DTXSID (DSSTox Substance Identifier) is the curated identifier assigned by the EPA DSSTox database. The DTXSID ensures stereochemistry, salts, and mixtures are systematically linked to an exact chemical representation within the dashboard.

Can researchers export bulk data for chemical panels from the dashboard?

Yes. The dashboard features a Batch Search function capable of processing up to 10,000 identifiers simultaneously. Users can input substance names, CASRNs, DTXSIDs, InChIKeys, or monoisotopic masses and export selected property and bioactivity fields in CSV, Excel, or SDF formats.

What biological data are included in the ToxCast section?

The ToxCast section compiles results from quantitative high-throughput screening assays that evaluate chemical interactions across cellular pathways, nuclear receptors, and enzymatic targets. Assays quantify concentration-response curves, identifying half-maximal activity concentrations (AC50) to evaluate mechanistic bioactivity.

How does the dashboard support FAIR data principles in environmental testing?

By standardizing chemical substance identifiers, exposing persistent DTXSID mappings, and providing open programmatic APIs, the platform adheres to modern research data standards. For publications documenting dashboard analyses, linking formal persistent identifiers such as a Crossref DOI ensures that toxicological workflows and datasets remain transparent and reproducible.

Sources

• US Environmental Protection Agency. “CompTox Chemicals Dashboard.” https://comptox.epa.gov/dashboard/ (Read November 8, 2026).
• US Environmental Protection Agency. “CompTox Chemicals Dashboard Overview.” https://www.epa.gov/chemical-research/comptox-chemicals-dashboard (Read November 8, 2026).
• US Environmental Protection Agency. “CompTox Chemicals Dashboard Help.” https://www.epa.gov/comptox-tools/comptox-chemicals-dashboard-help (Read November 8, 2026).
• US Environmental Protection Agency. “Chemicals Dashboard Help: Basic Search.” https://www.epa.gov/comptox-tools/chemicals-dashboard-help-basic-search (Read November 8, 2026).
• US Environmental Protection Agency. “Chemicals Dashboard Help: Batch Search.” https://www.epa.gov/comptox-tools/chemicals-dashboard-help-batch-search (Read November 8, 2026).
• US Environmental Protection Agency. “Distributed Structure-Searchable Toxicity (DSSTox) Database.” https://www.epa.gov/chemical-research/distributed-structure-searchable-toxicity-dsstox-database (Read November 8, 2026).