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Compound Groups

Compound groups are groups of chemicals that share structural or chemical features. In most cases, hazard lists will assign hazards to individual substances. Compound groups are useful because in some cases, lists will instead identify a group of structurally similar compounds (such as lead compounds) as all having the same hazard. The Pharos staff is in the process of establishing and populating compound groups, and associating warnings from the hazard lists with them. The table below indicates how each compound group is populated, and what is the status of its population.
Compound Groups
COMPOUND GROUP NAME POPULATION STATUS DATE POPULATED DESCRIPTION PROFILE TYPE # MEMBERS # HAZARDS
Procainamide, its salts and derivatives incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Potassium Titanates incomplete This compound group has not yet been assigned a structural definition. other 5 1
POLYISOCYANATE COMPOUNDS complete 07/24/17

This compound group is defined by the SMARTS string ([NX2:2]=[C:1]=[OX1:3].[NX2:2]=[C:1]=[OX1:3]), subtracting any compounds whose name contains "polymer". This SMARTS search unfortunately captures polymers made from isocyanates, because their structures are often represented by individual monomers. For more information on SMARTS, see https://en.wikipedia.org/wiki/Smiles_arbitrary_target_specification.

structure 575 3
Polyhalogenated triazines (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 7 12
Polyhalogenated phthalates/benzoates/imides (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 21 12
Polyhalogenated phenol-aliphatic ethers (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 14 12
Polyhalogenated phenol derivatives (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 10 12
Polyhalogenated organophosphates (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 38 12
Polyhalogenated diphenyl ethers (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 19 12
Polyhalogenated carbocycles (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 40 12
Polyhalogenated bisphenol aliphatics and functionalized (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 42 12
Polyhalogenated benzenes (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 20 12
Polyhalogenated benzene aliphatics and functionalized (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 22 12
Polyhalogenated benzene alicycles (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 4 12
Polyhalogenated aliphatic chains (NAS OFR subclass) complete 05/21/19

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

fixed list 42 12
Polyhalogenated aliphatic carboxylate (NAS OFR subclass) complete

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

6 12
Polyhalogenated alicycles (NAS OFR subclass) complete

This compound group is populated from a National Academies of Science report "A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019)" available at https://www.nap.edu/catalog/25412/a-class-approach-to-hazard-assessment-of-organohalogen-flame-retardants

20 12
polyethlyenepolyamines with the exception of those specified elsewhere in Annex VI of Regulation (EC) No 1272/2008 incomplete

This compound group is populated by taking the more general compound group and subtracting the chemicals found in the relevent Annex.

other 0 7
polyethlyenepolyamines incomplete

This compound group has not yet been assigned a structural definition.

structure 1 0
Polycyclic synthetic musks - Biomonitoring CA incomplete

This group is populated from the list at https://biomonitoring.ca.gov/chemicals

fixed list 0 1
Polycyclic Aromatic Hydrocarbons (PAHs) - Apple RSL complete

This compound group is populated from Apple's Regulated Substances Specification

fixed list 38 1
POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) complete

This list is drawn from:

other 95 19
POLYCYCLIC AROMATIC HYDROCARBONS (PAH) (US NIH RoC) incomplete

This compound group has not yet been assigned a structural definition.

19 0
Polycyclic Aromatic Compounds (TRI Category) 03/09/21

This compound group was populated using a list of chemicals that are reportable under the MA Toxics Use Reduction Act (TURA). See https://www.mass.gov/guides/massdep-toxics-use-reduction-program#-listed-chemicals- for more information.

fixed list 31 7
POLYCYCLIC AROMATIC COMPOUNDS (OSHA EXCLUSIONS) complete This compound group is defined by a list in the US EPA's Toxics Release Inventory (TRI) Basis of OSHA Carcinogens document, available at https://www.epa.gov/toxics-release-inventory-tri-program/tri-basis-osha-carcinogens. fixed list 24 6
POLYCYCLIC AROMATIC COMPOUNDS - Compound Group incomplete This compound group has not yet been assigned a structural definition. other 102 6
Polychlorophenols and their sodium salts 04/13/20 9 2
Polychlorinated terphenyls (PCTs) incomplete This compound group has not yet been assigned a structural definition. other 1 5
POLYCHLORINATED NAPHTHALENES (PCN) incomplete

This compound group has not yet been assigned a structural definition.

other 20 19
POLYCHLORINATED DIBENZOFURANS (PCDF) incomplete This compound group has not yet been assigned a structural definition. other 10 20
POLYCHLORINATED DIBENZO-P-DIOXINS (PCDD) incomplete This compound group has not yet been assigned a structural definition. other 8 27
POLYCHLORINATED BIPHENYLS (PCBs) incomplete

This compound group has not yet been assigned a structural definition.

other 240 36
POLYCHLORINATED ALKANES incomplete This compound group has not yet been assigned a structural definition. other 68 12
Polybrominated terphenyls (PBT) incomplete

This compound group was populated from the 2016 GADSL list at http://www.gadsl.org/

other 7 1
Polybrominated Diphenyl Ethers (PBDEs) - Apple RSL complete

This compound group is populated from Apple's Regulated Substances Specification

fixed list 23 1
POLYBROMINATED DIPHENYL ETHERS (PBDE) incomplete This compound group has not yet been assigned a structural definition. other 42 35
Polybrominated dibenzofurans incomplete This compound group has not yet been assigned a structural definition. other 0 2
Polybrominated dibenzodioxins incomplete

This compound group has not yet been assigned a structural definition.

other 0 1
POLYBROMINATED BIPHENYLS (PBBs) complete

This compound group was populated from the 2016 GADSL list at http://www.gadsl.org/

other 56 45
polyacrylamides incomplete 4 0
Piproctanyl salts incomplete

This compound group has not yet been assigned a structural definition.

other 0 3
Pipradrol and its salts incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Piperazine salts incomplete

This compound group is defined by the SMILES string 'C1CNCCN1'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

other 3534 0
Pipazetate and its salts incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Pigments containing or manufactured with chlorine complete 07/19/23

This compound group is populated with ChemForward's inadvertent PCB (iPCB) Pigment Resources - pigments with "Yes" for "Contains Chlorine?" or a "Yes" for "Manufactured using chlorine solvent?".

fixed list 177 0
PHTHALATES (orthophthalates) complete

This compound group is defined by a substructure search of PubChem using the SMILES string 'COC(=O)c1[cH][cH][cH][cH]c1C(=O)OC'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 639 12
Phthalates - Apple RSS complete

This compound group is populated from Apple's Regulated Substances Specification

fixed list 51 1
Phenyltin compounds in progress This compound group is defined by the SMILES string 'C1=CC=C(C=C1)[Sn]'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system. structure 234 15
PHENYLHYDRAZINE SALTS in progress

This compound group is defined by the SMILES string 'C1=CC=C(C=C1)NN'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

other 4 6
Phenylenediamine compounds incomplete

This compound group was populated from the 2016 GADSL list at http://www.gadsl.org/

other 16 0
Phenyl arsenic compounds in progress

This compound group is defined by the SMILES string '[As][CH]1=[CH][CH]=C([CH]=[CH]1)'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 0 37
Phenothiazine and its compounds incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Phenol, isopropylated, phosphate (3:1) - EPA PBT complete 07/12/23

EPA's background information about PBT define this compound group as a family of structures in which each of the three aryl groups have at least one isopropyl group: Tris(3-isopropylphenyl) phosphate, Tri(isopropylphenyl) phosphate, Tri(4-isopropylphenyl) phosphate

fixed list 3 1
Phenol, alkylation products (mainly in para position) with C12-rich branched alkyl chains from oligomerisation, covering any individual isomers and/ or combinations thereof (PDDP) complete 02/27/23

full name: Phenol, alkylation products (mainly in para position) with C12-rich branched alkyl chains from oligomerisation, covering any individual isomers and/ or combinations thereof (PDDP)

ECHA chemical group parent

3 8
Phenmetrazine, its derivatives and salts incomplete This compound group has not yet been assigned a structural definition. structure 1 1
PFNA, Perfluorononan-1-oic-acid and its sodium and ammonium salts complete 02/27/23

ECHA chemical group parent

other 3 5
PFNA, Perfluorononan-1-oic-acid and its salts incomplete

This compound group has not yet been assigned a structural definition.

other 3 4
PFAS soluable in DMSO - EPAPFASIV complete 08/14/23

This compound group is populated from EPAPFASIV's list. EPA filtered several publicly available PFAS lists to exclude most high (>500) and low (<50) molecular weight compounds, aromatic compounds, metal-containing compounds, and chemicals with a low ratio of fluorine to carbon. The PFAS chemicals in this list are in the current inventory found to be soluble in DMSO.

fixed list 437 14
PFAS - OECD Comprehensive Global Database of PFASs (2018) complete

OECD's Comprehensive Global Database of PFASs

4747 13
Petroleum, Crude oil incomplete This compound group has not yet been assigned a structural definition. other 2 1
Petroleum products incomplete This compound group has not yet been assigned a structural definition. other 7 2
Petroleum Process Streams complete 03/10/23

EPA's Partially Exempt Petroleum Process Streams list

from EPA's Chemical Data Reporting: https://www.epa.gov/chemical-data-reporting/partially-exempt-petroleum-process-streams

fixed list 636 0
Petroleum distillates incomplete This compound group has not yet been assigned a structural definition. other 118 2
Petrolatum (petroleum), treated and untreated incomplete This compound group has not yet been assigned a structural definition. other 34 0
Persulfate salts incomplete

This compound group is defined by the SMILES string '[O-]S(=O)(=O)OOS(=O)(=O)[O-]'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system. Persulfate salts populated per SIDS Initial Assessment Report For SIAM 20 http://www.chem.unep.ch/irptc/sids/oecdsids/Persulfates.pdf

other 4 3
Perfluorooctyl silanes incomplete

This compound group has not yet been assigned a structural definition.

other 0 0
Perfluorooctanoic acid inorganic salts incomplete

This compound group is defined by the SMILES string 'C(=O)(C(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)O'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

other 0 2
perfluorooctanoic acid (PFOA), its salts and PFOA-related substances incomplete other 79 9
Perfluorooctanoic Acid (PFOA) Salts, and Its Precursors incomplete This compound group has not yet been assigned a structural definition. other 3 10
PERFLUOROOCTANOATE (PFOA, C-8) SALTS incomplete

Salts of perfluorooctanoic acid (PFOA).

structure 2 24
Perfluorooctane sulfonyls incomplete

Compounds that contain one of the following groups: C8F17SO2-, C8F17SO3- or C8F17SO2N-.

structure 1 18
Perfluorooctane sulfonates C8F17SO2X (X = OH, Metal salt, halide, amide, and other derivatives including polymers) (PFOS), all members incomplete

This compound group was populated from the 2016 GADSL list at http://www.gadsl.org/

other 19 12
Perfluorooctane Sulfonates (PFOS) and PFOS salts in Google's MRSL complete 02/12/21

This compound group was populated from the Google Manufacturing Restricted Substances Specification (v1.0) (TTD_3549)

fixed list 28 2
Perfluorooctane sulfonates (PFOS) complete

This compound group is defined by the SMILES/SMARTS string "C(C(C(C(C(F)(F)S(=O)(=O)O)(F)F)(F)F)(F)F)(C(C(C(F)(F)F)(F)F)(F)F)(F)F" and populated from a substructure search of PubChem. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 41 32
Perfluorooctane sulfonamides incomplete

This compound group has not yet been assigned a structural definition.

other 5 1
Perfluorohexanesulfonic acid and its salts (PFHxS) complete 02/27/23

ECHA chemical group parent

37 22
Perfluorohexane sulfonic acid (PFHxS), its salts and PFHxS-related compounds incomplete

This compound group has not yet been assigned a structural definition.

other 38 15
Perfluoroheptanoic acid and its salts 04/24/23

ECHA defined chemical group

4 10
Perfluorocarboxylic Acids (PFCAs), Long-Chain (C9-C20), their Salts, and their Precursors incomplete

This compound group has not yet been assigned a structural definition.

other 0 5
PERFLUOROCARBONS, SHORT-CHAIN incomplete This compound group has not yet been assigned a structural definition. other 6 13
Perfluorocarbons (PFCs) in Google's MRSL complete 02/12/21

This compound group was populated from the Google Manufacturing Restricted Substances Specification (v1.0) (TTD_3549)

fixed list 9 1
Perfluorobutanoic acid and its salts and precursors incomplete

This compound group has not yet been assigned a structural definition.

other 0 0
Perfluorobutane sulfonic acid (PFBS) and its salts incomplete

This compound group has not yet been formally defined.

structure 12 10
Perfluoroalkyl phosphate compounds incomplete

This compound group has not yet been assigned a structural definition.

23 12
Perfluoroalkyl carbonyl compounds incomplete

This group was populated from the OECD's Comprehensive Global Database of Per- and Polyfluoroalkyl Substances (PFASs) at http://www.oecd.org/chemicalsafety/portal-perfluorinated-chemicals/.

515 12
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) - Biomonitoring CA incomplete

This group is populated from the list at https://biomonitoring.ca.gov/chemicals/perfluorochemicals-pfcs

fixed list 12 16
Perfluoroalkane sulfonyl compounds incomplete

This group was populated from the OECD's Comprehensive Global Database of Per- and Polyfluoroalkyl Substances (PFASs) at http://www.oecd.org/chemicalsafety/portal-perfluorinated-chemicals/.

641 12
PERFLUORINATED ALKYL SUBSTANCES (PFAS), SHORT-CHAIN incomplete

This compound group has not yet been assigned a structural definition.

other 4 15
PERFLUORINATED ALKYL SUBSTANCES (PFAS), LONG-CHAIN incomplete

This compound group has not yet been assigned a structural definition.

other 192 17
Perchlorates incomplete

This compound group has not yet been assigned a structural definition and is incomplete.

structure 25 1
Perboric acid (H3BO2(O2)), and other sodium salts incomplete This compound group is defined by the SMILES string '[Na+].[O-]OB=O'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system. other 32 0
Per- and polyfluoroalkyl ether-based compounds incomplete

This group was populated from the OECD's Comprehensive Global Database of Per- and Polyfluoroalkyl Substances (PFASs) at http://www.oecd.org/chemicalsafety/portal-perfluorinated-chemicals/.

365 12
Per and Polyfluorinated Alkyl Substances (PFAS) / Perfluorinated Compounds (PFCs) incomplete

This group is populated by:

  • Global Database of Per- and Polyfluoroalkyl Substances (PFASs) at http://www.oecd.org/chemicalsafety/portal-perfluorinated-chemicals/ 
  • PFAS Master List of PFAS Substances (https://comptox.epa.gov/dashboard/chemical-lists/PFASMASTER), a consolidated list of PFAS substances compiled by the EPA and includes the EPA research list of PFAS compiled from internal, literature, and public sources; complete list of DMSO-solubilized PFAS in EPA's ToxCast inventory; a prioritized subset of the larger ToxCast chemical inventory; a list of chemicals procured but found to be insoluble in DMSO above 5mM; the OECD New Comprehensive Global Database; KEMI Swedish Chemicals Agency Report; compilation by community effort in 2015; structure-based Markush PFAS categories (capabilities under development); PFAS structures containing a specific defined substructures; and PFAS chemicals without explicit structures (polymers and other UVCB chemicals)
  • Members of subgroups
other 10774 12
Pentanol isomers with the exception of those specified elsewhere in Annex VI of Regulation (EC) No 1272/2008 incomplete

This compound group has not yet been assigned a structural definition.

0 3
Pentanol isomers (MAK list) complete

This compound group has not yet been assigned a structural definition.

fixed list 11 4
Pentane isomers incomplete This compound group has not yet been assigned a structural definition. other 5 1
Pentachlorophenol salts and esters complete

This compound group is defined by a substructure search of PubChem the SMILES/SMARTS string "C1(=C(C(=C(C(=C1Cl)Cl)Cl)Cl)Cl)[OD1] plus C1(=C(C(=C(C(=C1Cl)Cl)Cl)Cl)Cl)[O]C(C)=O". The setting "Remove any explicit hydrogens before searching" was deselected from each substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 118 12
Pemoline and its salts incomplete This compound group has not yet been assigned a structural definition. structure 1 1
PBDEs In Commercial Pentabromodiphenyl Ether incomplete This compound group has not yet been assigned a structural definition. fixed list 13 37
PBDEs in Commercial Octabromodiphenyl Ether incomplete This compound group is defined by a list in the Stockholm Convention, available at http://chm.pops.int/TheConvention/ThePOPs/TheNewPOPs/tabid/2511/Default.aspx fixed list 4 37