What is a GreenScreen Assessment? GreenScreen® for Safer Chemicals is a method for chemical hazard assessment designed to identify chemicals of high concern and safer alternatives. The hazard levels for each human or environmental health endpoint are assigned by a toxicologist using the GreenScreen protocol developed by Clean Production Action.
What makes a hazard high or low confidence?
High confidence can result from either from a high confidence list, or high quality data for the chemical or a strong analog.
Low confidence is based on lower confidence studies, data from a weak analog, estimated data from a suitable analog, or less specific or less authoritative lists.
Hazard Lists FAQ
Where do these hazard assignments come from?
The health and environmental hazards in the hazard summary table have been associated with this substance in hazard lists developed by scientific bodies such as the US EPA or International Agency for Research on Cancer (IARC).
How do I see all the hazard lists the chemical is on?
If there are multiple hazard listings for an endpoint, there will be a button under “Other Lists” in the full Hazard Lists table indicating how many other listings exist for this chemical. Clicking on this button will expand a list of all hazard listings for the endpoint.
What are the asterisks in the Hazard List table?
In most instances, they indicate a hazard is assigned because the chemical is a member of a group. Scientific hazard lists sometimes specify a chemical group (such as trimethyltin compounds) without a defined list of CASRNs. For these, Pharos creates a list of CASRNs that meet the group criteria. Move your cursor over the asterisk for the group name, and click the asterisk to see the group and its definition. See the Compound Group Population Project for more information on how these groups are determined.
Less frequently, an asterisk may indicate a hazard is assigned because the chemical has been identified as a synonym of another chemical that has been specified by the hazard list. In these cases, moving your cursor over the asterisk will indicate the synonym chemical name and CAS number, and clicking on it will redirect to that chemical’s complete profile.
GreenScreen® assessments published after 1/1/19 expire at 5-year intervals, except for assessments of Benchmark 1 chemicals, which do not expire. Assessments published before this date expire after 3 years. It is the responsibility of users to verify whether an assessment has expired. Expired assessments may not be used to make claims of any sort or receive credit under standards which incorporate GreenScreen. Results contained within expired assessments should be reviewed carefully, as significant new information may change hazard endpoint classifications, and therefore, GreenScreen Benchmark scores. Users take all responsibility for actions based on expired assessments. Users are encouraged to obtain an updated assessment and Benchmark score. Please visit the GreenScreen website for more information.
External Resources FAQ
What kind of information do these other sites provide?
PubChem provides information on the biological activities of over 90 million small molecules. It is the source of the physical properties and many of the synonyms for chemicals in Pharos. It is managed by the U.S. National Library of Medicine.
ChemIDplus is a database within ToxNet that contains over 400,000 chemical records that include chemical IDs and toxicology data. It is managed by the U.S. National Library of Medicine.
OECD eChemPortal provides information on chemical properties and direct links to collections of information prepared for government chemical review programmes at national, regional, and international levels. The eChemPortal is an effort of the Organisation for Economic Co-operation and Development (OECD) in collaboration with numerous governments and NGOs.
HSDB (Hazardous Substances DataBase) is a database within ToxNet that focuses on the toxicology of potentially hazardous chemicals. It provides information on human exposure, industrial hygiene, emergency handling procedures, environmental fate, regulatory requirements, nanomaterials, and related areas. It is managed by the U.S. National Library of Medicine.
CPCat (Chemical and Product Categories) is an EPA database containing information mapping more than 43,000 chemicals to a set of terms categorizing their usage or function.
Pharos Chemical and Material Library is also managed by the Healthy Building Network and is the source of all the hazard data in Pharos. Additionally, it contains information on how chemicals are produced, and what building products they can be found in. The site requires a subscription, but a free trial is available.
EPA's CompTox Chemistry Dashboard contains chemical properties, environmental fate, hazard information, and links to additional databases.
PubMed comprises more than 28 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
EPA's Toxicity Forecaster (ToxCast) generates data and predictive models on thousands of chemicals of interest to the EPA. ToxCast uses high-throughput screening methods and computational toxicology approaches to rank and prioritize chemicals.
International Toxicity Estimates for Risk (ITER) contains data in support of human health risk assessments. It is compiled by Toxicology Excellence for Risk Assessment (TERA) and contains data from CDC/ATSDR, Health Canada, RIVM, U.S. EPA, IARC, NSF International and independent parties offering peer-reviewed risk values.
ECHA Registration Dossiers contain chemical hazard information submitted to the European Chemicals Agency as part of manufacturers obligations under the EU’s chemical regulation, REACH.
US EPA Toxic Release Inventory (TRI) Program is a resource for learning about toxic chemical releases of a designated set of 692 chemicals and chemical categories into air, water bodies, and land by industrial and federal facilities as required under US federal law.
Remediation projects managed by Pure Earth provides a detailed description of each of their roughly 140 chemical remediation projects, including statistics, timelines, and partner organizations. Pharos links directly only to those with that refer to specific chemicals.
Pure Earth’s Toxic Sites Identification Program provides a database of chemical contamination in low- and middle-income countries with rich search criteria including chemical, population, region, industry source, and risk-ranking.
Why include data on chemical contamination and releases?
Chemicals can affect our health and environment throughout their life cycle - from extraction, refining, use, recycling, and disposal. The US EPA Toxic Release Inventory and Pure Earth database are rich sources of data on these effects in the US and abroad.
What are C2C hazards and what do these colors mean?
What are the C2C Hazards? The Cradle to Cradle Certified Product Standard establishes a Material Health Assessment Methodology which assigns hazard ratings to 24 individual human and environmental health endpoints. Roll your cursor over the abbreviations (C, M, R+D, etc) in the table to see the full name of each endpoint (Carcinogenicity, Mutagenicity, Reproductive Toxicity, etc). Organohalogen and Toxic Metal are classes of chemicals generally associated with significant human and environmental health issues and are specially treated in the C2C Standard.
The hazard rating is a Green-Yellow-Red-Grey color scheme based upon available toxicity and fate information:
Green: no hazard identified for the endpoint
Red: hazard identified for the endpoint
Grey: no data available for the endpoint
This tab shows the preliminary hazard ratings based upon hazard lists tracked in the Pharos Chemical & Material Library. During full assessment for certification purposes, Grey hazards must be filled by an accredited assessor and other list-based hazards may be overridden.
Why are these rating colors sometimes different from the GreenScreen or Pharos rating colors? The C2C hazard rating colors are similar to those used in the GreenScreen system and in Pharos, with some distinctions. Pharos has two additional rating colors - orange and purple - not used in the C2C or GreenScreen systems. Pharos orange, red and purple ratings generally encompass the C2C & GreenScreen red ranges. There are some distinctions between the GreenScreen and C2C thresholds that result in different color assignments that are under consideration for harmonization. See the Material Health Evaluation Programs Harmonization Opportunities Report for details. For substances that have been fully assessed under the GreenScreen protocol, there may be different colors due to the application of data from studies that provide information beyond that in the hazard lists.
If interested in assessing the chemicals in a product, please also review the link below describing "How to Use These Scores in a C2C Assessment".
How to Use These Scores in a C2C Assessment
The top table displays preliminary hazard ratings for individual endpoints based on the hazard lists a given chemical appears on. During the assessment, an accredited Cradle to Cradle Certified Material Health Assessor may override these list-based hazard ratings based on information from other sources. Additionally, a red hazard rating in any one endpoint does not automatically mean that a substance will be x-assessed and targeted for phase-out, as exposure relevant to the endpoint may be deemed non-plausible for the substance depending on the material and product context in which it is being assessed.
The bottom table (Full Hazard List by Endpoint) includes all warnings associated with the substance from each of the authoritative hazard lists used by C2C, as well as additional lists in the Pharos Chemical and Material Library. C2C lists are labeled with their C2C hazard rating (Red, Yellow, or Green), while non-C2C lists are labeled as "not rated".
The ratings for the hazard lists used in this tool are based on Table 9 in the Material Assessment Methodology, Cradle to Cradle Certified Version 3.0 with a few minor adjustments/additions to allow for direct mapping from GreenScreen list translator results for a subset of the covered lists. The v3.0 Material Assessment Methdology document can be found on the C2C Resources page at http://www.c2ccertified.org/resources/collection-page/cradle-to-cradle-certified-resources. For information on the relevant adjustments/additions, contact Matteo Kausch at email@example.com.
R: Red hazard level
Y: Yellow hazard level
G: Green hazard level
?: On a hazard list that has not been rated by C2C
-: Not listed on any C2C or Pharos hazard lists
Share 2,2',4,6-TETRACHLOROBIPHENYL (PCB-51)
The GreenScreen® for Safer Chemicals is a benchmarking system to rank the safety of chemicals on a 4 point hazard scale and encourage progress toward safer alternatives. Chemicals that have undergone a full GreenScreen assessment by Licensed GreenScreen Profilers are given a Benchmark score, which is the most authoritative. Chemicals that have been assessed using an automated comparison to hazard lists are given a List Translator score, which is less authoritative. Full GreenScreen assessments trump results from List Translator scoring.
GreenScreen Scores in order from highest concern to lowest concern are: