About Pharos



Pharos provides resources to assess human and environmental health hazards of chemicals and building materials, plus tools to collaborate to find safer alternatives. The goal of this effort is to reduce the use of hazardous chemicals and improve the inherent safety of materials and products.

Who We Are

Pharos is a project of Healthy Building Network (HBN) a nonprofit founded in 2000 to reduce the use of hazardous chemicals in building products as a means of improving human health and the environment. Pharos is comprehensive, not limited to chemicals used in the building industry.

Data Sources & Analyses

Pharos integrates the following data sources and analyses to show what is known about the hazards of chemicals and facilitate comparisons:

  • Hazard listings - Pharos aggregates over 40 authoritative hazard lists to make associations between chemicals and 22 specific human and environmental health endpoints. We constantly monitor the sources to keep up to date. For a list of all the hazard sources and to learn more, check out the Pharos system description.

  • Restricted substance lists - Listings of chemicals whose use is restricted and/or managed by regulatory or corporate policy or subject to voluntary program guidance. Pharos references over 30 restricted substance lists. To learn more, check out the Pharos system description, starting on page 20.

  • Exempt & Positive lists - Listings of chemicals that have been exempted from regulatory actions (such as EPA VOC exemptions) or are preferable for use for certain applications based upon an assessment of lower hazard (such as the EPA SCIL list). Beware, these lists generally have constraints - exemptions of preferences based on a limited set of health endpoints or for limited uses

  • List Screening - Pharos is an approved GreenScreen Automator, assessing all chemicals in the database against the GreenScreen List Translator to generate LT scores identifying known chemicals of high concern.

  • Hazard assessments - Pharos provides access to all GreenScreen™ hazard assessments published for public use. These toxicological assessments benchmark the inherent hazards of chemicals across a broad range of health endpoints.

  • Identification - Over 100,000 substances are listed in Pharos, searchable by over 270,000 CASRNs and synonyms utilizing the NIH PubChem and ChemIDplus databases.

  • Physical properties - chemical formulas and some key physical data are drawn from the NIH PubChem database.

  • Compound groups - Pharos is the home of the Compound Group Population Project which creates structural or other definitions for the chemical compound groups referenced by authoritative hazard lists. We use those definitions to associate relevant CASRN with those groups to ensure comprehensive list screening.

The above data is summarized in the Profile tab for each chemical.

The External Resources tab for each chemical provides links to information on that chemical in other databases that cover a range of topics:

  • Release - Releases to air, water, and land in the US are available from the USEPA Toxic Release Inventory database for almost 500 chemicals.

  • Contamination - Information on contaminated sites and remediation efforts around the globe are available from the Pure Earth Toxic Sites Identification Program Global Database.

  • And more - Links to other sites with information on chemical manufacturing, uses, physical properties, toxicity, exposure, REACH registrations, and more. Links include PubChem, ChemIDPlus, OECD eChemPortal, ECHA, and Pharos.

Get this data into your application

Most of the data displayed in the Profile tab for each chemical is available through bulk download and an API for use in your applications. Contact us at sales@healthybuilding.net for information.


Discussions provide a place to discuss chemical hazard issues. Pharos also hosts collaborative Projects such as the Compound Group Population project mentioned above and a project exploring safer alternatives for chemicals used in plastic packaging.

Learn more

Roll your cursor over headings and titles and “?” icons and click on FAQs for more descriptive information about the sources used and functions provided throughout the site. The Help page provides more pointers. 

What happened to the Chemical Hazard Data Commons?

The Chemical Hazard Data Commons was created as an offshoot of Pharos to test collaborative workspaces, crowdsourcing hazard data, and new ways to share information. After two years of testing we have taken what we learned and brought it back to Pharos to make a powerful tool to support alternatives assessment. Additional background information about the Chemical Hazard Data Commons.


Pharos is supported by the Forsythia Foundation, the Lisa & Douglas Goldman Fund, and the John Merck Fund.


Advisory Committee
  • Martin Mulvihill, PhD, Safer Made & UC Berkeley Center for Green Chemistry
  • Sally Edwards, Sc.D., UMass Lowell, Lowell Center for Sustainable Production
  • Catherine Bobenhausen, CIH, CSP, LEED AP BD+C, Vidaris
  • Mike Schade, Safer Chemicals, Healthy Families
  • Shari Franjevic, Clean Production Action
  • Annie Schmidt, Seagate
  • Anne Lebleu, Arabella Advisors
Managing Staff
  • Michel Dedeo - Manager of Chemical Information Systems
Engineering Staff
  • Jon Stavis
  • Sarah Gilberg

And, a special thanks to the following people, who have dedicated significant volunteer time to helping shape the new Pharos:

  • Akos Kokai
  • Ann Blake