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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
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
Phthalates - Apple RSS complete

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

fixed list 51 1
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 712 12
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
Pipazetate 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 3533 0
Pipradrol and its salts incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Piproctanyl salts incomplete

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

other 0 3
polyacrylamides incomplete 4 0
POLYBROMINATED BIPHENYLS (PBBs) complete

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

other 56 45
Polybrominated dibenzodioxins incomplete

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

other 0 1
Polybrominated dibenzofurans incomplete This compound group has not yet been assigned a structural definition. other 0 2
POLYBROMINATED DIPHENYL ETHERS (PBDE) incomplete This compound group has not yet been assigned a structural definition. other 42 35
Polybrominated Diphenyl Ethers (PBDEs) - Apple RSL complete

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

fixed list 23 1
Polybrominated terphenyls (PBT) incomplete

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

other 7 1
POLYCHLORINATED ALKANES incomplete This compound group has not yet been assigned a structural definition. other 68 12
POLYCHLORINATED BIPHENYLS (PCBs) incomplete

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

other 240 36
POLYCHLORINATED DIBENZO-P-DIOXINS (PCDD) incomplete This compound group has not yet been assigned a structural definition. other 8 27
POLYCHLORINATED DIBENZOFURANS (PCDF) incomplete This compound group has not yet been assigned a structural definition. other 10 20
POLYCHLORINATED NAPHTHALENES (PCN) incomplete

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

other 20 19
Polychlorinated terphenyls (PCTs) incomplete This compound group has not yet been assigned a structural definition. other 1 5
Polychlorophenols and their sodium salts 04/13/20 9 2
POLYCYCLIC AROMATIC COMPOUNDS - Compound Group incomplete This compound group has not yet been assigned a structural definition. other 102 6
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 (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 HYDROCARBONS (PAH) (US NIH RoC) incomplete

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

19 0
POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) complete

This list is drawn from:

other 95 19
Polycyclic Aromatic Hydrocarbons (PAHs) - Apple RSL complete

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

fixed list 38 1
Polycyclic synthetic musks - Biomonitoring CA incomplete

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

fixed list 0 1
polyethlyenepolyamines incomplete

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

structure 1 0
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
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
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 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 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 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 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 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 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 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 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 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 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 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 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
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
Potassium Titanates incomplete This compound group has not yet been assigned a structural definition. other 5 1
Procainamide, its salts and derivatives incomplete This compound group has not yet been assigned a structural definition. structure 1 1
Propanedinitrile, (and related derivatives) incomplete This compound group has not yet been assigned a structural definition. other 141 0
Propanenitrile, (and related derivatives) incomplete This compound group has not yet been assigned a structural definition. other 322 0
PROPYLENE GLYCOL & GLYCOL ETHERS (PGES) incomplete

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

other 28 0
proteases incomplete

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

functional use 2 0
proteases 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.

1 5
PVC related polymers incomplete This compound group has not yet been assigned a structural definition. other 134 2
Pyrethrins incomplete This compound group has not yet been assigned a structural definition. other 9 2
pyrethrins including cinerins incomplete

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

other 4 0
pyrethrins including cinerins, 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.

1 6
Pyrethroid pesticides - Biomonitoring CA incomplete

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

fixed list 0 1
Pyrethroids incomplete This compound group has not yet been assigned a structural definition. other 32 3
Pyrolysis products of organic materials with high levels of PAHs incomplete

This list is populated from the 2018 MAK document, where listings for specific chemicals were not available:

"Many of the PAH which occur regularly in pyrolysis products are carcinogenic in animal studies. They are present at particularly high levels in brown coal tars (soft coal tars), coal tars (black coal tars), coal tar pitches, coal tar oils, coke oven emissions."

other 15 0
QUATERNARY AMMONIUM COMPOUNDS complete 07/09/19

This compound group was populated from a manual search of the Pharos database. 

other 120 1
QUINOLINE STRONG ACID SALTS complete 07/09/19

Strong acid salts are listed at https://comptox.epa.gov/dashboard/dsstoxdb/mixture_search?cid=1798

fixed list 6 4
Radioactive Elements 11 0
Radioiodines, including iodine-131 incomplete

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

0 6
Radionuclides incomplete

This group has not been assigned a structural definition yet.

3 5
Radionuclides, alpha-particle-emitting, internally deposited incomplete

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

0 6
Radionuclides, beta-particle-emitting, internally deposited incomplete

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

0 6
Raffinates (petroleum), and various treated and processed fractions incomplete This compound group has not yet been assigned a structural definition. other 10 0
Reaction products of 1,3,4-thiadiazolidine-2,5-dithione, formaldehyde and 4-heptylphenol, branched and linear (RP-HP) complete 02/27/23

with ≥0.1% w/w 4-heptylphenol, branched and linear (4-HPbl)

ECHA chemical group parent

2 5
Refractory Ceramic Fibers (with alkaline oxide and alkali earth oxide content less or equal to 18 % by weight) incomplete This compound group has not yet been assigned a structural definition. other 5 8
Refractory Ceramic Fibres with the exception of those specified elsewhere in Annex VI of Regulation (EC) No 1272/2008, [with alkaline oxide and alkali earth oxide content less or equal to 18 % by weight] incomplete

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

other 3 13
Refractory Ceramic Fibres, Special Purpose Fibres, with the exception of those specified elsewhere in Annex XVII of Regulation (EC) No 1907/2006, [with alkaline oxide and alkali earth oxide content less or equal to 18 % by weight] incomplete

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

3 11
Residual (heavy) fuel oils incomplete

This group has not been assigned a structural definition yet.

0 4
Residual oils (petroleum), treated incomplete This compound group has not yet been assigned a structural definition. other 12 0
Residues (coal tar) incomplete This compound group has not yet been assigned a structural definition. other 3 1
Residues (petroleum) and similar products incomplete This compound group has not yet been assigned a structural definition. other 58 0
Resin acids and Rosin acids, salts and hydrogenated esters incomplete This compound group has not yet been assigned a structural definition. other 4 0
retinol/retinyl esters, when in daily dosages in excess of 10,000 iu, or 3,000 retinol equivalents incomplete

This group has not been assigned a structural definition yet.

0 4
Rhodium compounds, inorganic in progress This compound group is defined by the SMILES string '[Rh]' and subsequently filtered to remove substances containing '[C]'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system. other 0 1
Salinomycin, salts incomplete

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

other 0 1
salts and esters of dinex incomplete

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

other 0 5
salts and esters of dinosam incomplete

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

other 0 5
salts and esters of dinoseb, 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 2 12
Salts and esters of dinoseb, with the exception of those specified elsewhere in Annex XVII of Regulation (EC) No 1907/2006 incomplete

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

other 2 4
salts and esters of dinoterb - ECHA complete 05/26/23

ECHA defined chemical group

fixed list 1 13
salts and esters of MCPA incomplete

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

other 0 5
salts and esters of MCPB incomplete

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

other 0 1
salts of 2,4-D incomplete

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

structure 3 5
salts of 2,4-DB incomplete

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

structure 1 3
Salts of 3,3'-dichlorobenzidine complete

This compound group is defined by the SMILES string '[CH1]1=[CH1]C(=C([CH1]=C1C2=[CH1]C(=C([CH1]=[CH1]2)[ND1])[ClD1])[ClD1])[ND1]'. The setting "Remove any explicit hydrogens before searching" was deselected from the substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 9 11
Salts of 3,3'-dimethoxybenzidine complete

This compound group is defined by a substructure search of PubChem the SMILES/SMARTS string "[CH1]1=[CH1]C(=C([CH1]=C1C2=[CH1]C(=C([CH1]=[CH1]2)[ND1])O[CH3])O[CH3])[ND1]". The setting "Remove any explicit hydrogens before searching" was deselected from the substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 5 8
Salts of 4-aminobiphenyl complete

This compound group is defined by the SMILES string '[CH1]1=[CH1][CH1]=C([CH1]=[CH1]1)C2=[CH1][CH1]=C([CH1]=[CH1]2)[ND1]'. The setting "Remove any explicit hydrogens before searching" was deselected from the substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 6 11
salts of 4,4'-bi-o-toluidine, salts of 3,3'-dimethylbenzidine, salts of o-tolidine incomplete

This compound group is defined by a substructure search of PubChem the SMILES/SMARTS string "[CH3]C1=C([CH1]=[CH1]C(=[CH1]1)C2=[CH1]C(=C([CH1]=[CH1]2)[ND1])[CH3])[ND1]". The setting "Remove any explicit hydrogens before searching" was deselected from the substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 9 5
salts of 4,4'-carbonimidoylbis[N,N-dimethylaniline] complete

The IARC monograph Auramine and Auramine Production in volume 99 lists the following commercially relevant salts: sulfate, nitrate, nitrite, acetates, propionates, bromides, iodides, salts of alkyl-, aralkyl-, or arylsulfonic acids, thiocyanates, and phosphates. CASRN were found for sulfate, nitrate and acetate.

https://monographs.iarc.fr/wp-content/uploads/2018/06/mono99-9.pdf

other 4 6
Salts of 4,4'-methylenebis(2-chloroaniline) complete

This compound group is defined by the SMILES/SMARTS string "[C;D2]1=[C;D2]C(=C([C;D2]=C1[C;D2]C2=[C;D2]C(=C([C;D2]=[C;D2]2)[N;D1])[Cl;D1])[Cl;D1])[N;D1]" 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 4 12
Salts of 4,4'-oxydianiline complete

This compound group is defined and populated from ECHA's Substance Infocard for Salts of 4,4'-dianiline https://echa.europa.eu/substance-information/-/substanceinfo/100.239.146

fixed list 1 7
salts of 4,4'-thiodianiline complete

This compound group is defined by a substructure search of PubChem the SMILES/SMARTS string "[CH1]1=[CH1]C(=[CH1][CH1]=C1[SD2]C2=[CH1][CH1]=C([CH1]=[CH1]2)[ND1])[ND1]". The setting "Remove any explicit hydrogens before searching" was deselected from the substructure search. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 2 5
salts of aconitine incomplete

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

other 1 3
Salts of aniline in progress

This compound group is defined by the SMILES string '[CH]1=[CH][CH]=C([CH]=[CH]1)[NH2]'. For more information on SMILES, see https://en.wikipedia.org/wiki/Simplified_molecular-input_line-entry_system.

structure 5 14
salts of aniline - ECHA chemical group complete 05/26/23 fixed list 11 13