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Assessing and Managing Chemicals under TSCA

List of Chemicals Undergoing Prioritization

As required under section 6(b) of the Toxic Substances Control Act (TSCA), EPA must conduct a prioritization process to determine if chemical substances are a high or low priority for risk evaluation.

On March 20, 2019, EPA issued the following list of 40 chemicals to begin the prioritization process. TSCA requires EPA to publish this list of 40 chemicals to begin the prioritization process to designate 20 chemicals as “high-priority” for subsequent risk evaluation and to designate 20 chemicals as “low-priority,” meaning that risk evaluation is not warranted at this time. Publication in the Federal Register activates a statutory requirement for EPA to complete the prioritization process in the next nine to twelve months, allowing EPA to designate 20 chemicals as high priority and 20 chemicals as low priority by December 2019.

Chemical Name CAS Docket Number Status*
High Priority Candidates
p-Dichlorobenzene 106-46-7 EPA-HQ-OPPT-2018-0446 Initiated
1,2-Dichloroethane 107-06-2 EPA-HQ-OPPT-2018-0427 Initiated
trans-1,2- Dichloroethylene 156-60-5 EPA-HQ-OPPT-2018-0465 Initiated
o-Dichlorobenzene 95-50-1 EPA-HQ-OPPT-2018-0444 Initiated
1,1,2-Trichloroethane 79-00-5 EPA-HQ-OPPT-2018-0421 Initiated
1,2-Dichloropropane 78-87-5 EPA-HQ-OPPT-2018-0428 Initiated
1,1-Dichloroethane 75-34-3 EPA-HQ-OPPT-2018-0426 Initiated
Dibutyl phthalate (DBP) (1,2-Benzene- dicarboxylic acid, 1,2- dibutyl ester) 84-74-2 EPA-HQ-OPPT-2018-0503 Initiated
Butyl benzyl phthalate (BBP) - 1,2-Benzene- dicarboxylic acid, 1- butyl 2(phenylmethyl) ester 85-68-7 EPA-HQ-OPPT-2018-0501 Initiated
Di-ethylhexyl phthalate (DEHP) - (1,2-Benzene- dicarboxylic acid, 1,2- bis(2-ethylhexyl) ester) 117-81-7 EPA-HQ-OPPT-2018-0433 Initiated
Di-isobutyl phthalate (DIBP) - (1,2-Benzene- dicarboxylic acid, 1,2- bis-(2methylpropyl) ester) 84-69-5 EPA-HQ-OPPT-2018-0434 Initiated
Dicyclohexyl phthalate 84-61-7 EPA-HQ-OPPT-2018-0504 Initiated
4,4'-(1-Methylethylidene)bis[2, 6-dibromophenol] (TBBPA) 79-94-7 EPA-HQ-OPPT-2018-0462 Initiated
Tris(2-chloroethyl) phosphate (TCEP) 115-96-8 EPA-HQ-OPPT-2018-0476 Initiated
Phosphoric acid, triphenyl ester (TPP) 115-86-6 EPA-HQ-OPPT-2018-0458 Initiated
Ethylene dibromide 106-93-4 EPA-HQ-OPPT-2018-0488 Initiated
1,3-Butadiene 106-99-0 EPA-HQ-OPPT-2018-0451 Initiated
1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta [g]-2-benzopyran (HHCB) 1222-05-5 EPA-HQ-OPPT-2018-0430 Initiated
Formaldehyde 50-00-0 EPA-HQ-OPPT-2018-0438 Initiated
Phthalic anhydride 85-44-9 EPA-HQ-OPPT-2018-0459 Initiated
*Status is listed as either:
  • Initiated – The first step of the prioritization process, and the chemical is currently undergoing a screening level review of reasonably available information to inform its priority designation;
  • Proposed – The second step of the prioritization process, when EPA proposes a chemical’s designation as either high or low priority for risk evaluation; or
  • High/Low - The final step of the prioritization process. This chemical has been designated as high or low priority for risk evaluation.
Chemical Name CAS Docket Number Status*
Low Priority Candidates
1-Butanol, 3-methoxy-, 1-acetate 4435-53-4 EPA-HQ-OPPT-2019-0106 Initiated
D-gluco-Heptonic acid, sodium salt (1:1), (2.xi.)- 31138-65-5 EPA-HQ-OPPT-2019-0107 Initiated
D-Gluconic acid 526-95-4 EPA-HQ-OPPT-2019-0108 Initiated
D-Gluconic acid, calcium salt (2:1) 299-28-5 EPA-HQ-OPPT-2019-0109 Initiated
D-Gluconic acid, .delta.-lactone 90-80-2 EPA-HQ-OPPT-2019-0110 Initiated
D-Gluconic acid, potassium salt (1:1) 299-27-4 EPA-HQ-OPPT-2019-0111 Initiated
D-Gluconic acid, sodium salt (1:1) 527-07-1 EPA-HQ-OPPT-2019-0112 Initiated
Decanedioic acid, 1,10-dibutyl ester 109-43-3 EPA-HQ-OPPT-2019-0113 Initiated
1-Docosanol 661-19-8 EPA-HQ-OPPT-2019-0114 Initiated
1-Eicosanol 629-96-9 EPA-HQ-OPPT-2019-0115 Initiated
1,2-Hexanediol 6920-22-5 EPA-HQ-OPPT-2019-0116 Initiated
1-Octadecanol 112-92-5 EPA-HQ-OPPT-2019-0117 Initiated
Propanol, [2-(2-butoxymethylethoxy)methylethoxy]- 55934-93-5 EPA-HQ-OPPT-2019-0118 Initiated
Propanedioic acid, 1,3-diethyl ester 105-53-3 EPA-HQ-OPPT-2019-0119 Initiated
Propanedioic acid, 1,3-dimethyl ester 108-59-8 EPA-HQ-OPPT-2019-0120 Initiated
Propanol, 1(or 2)-(2-methoxymethylethoxy)-, acetate 88917-22-0 EPA-HQ-OPPT-2019-0121 Initiated
Propanol, [(1-methyl-1,2-ethanediyl)bis(oxy)]bis- 24800-44-0 EPA-HQ-OPPT-2019-0122 Initiated
2-Propanol, 1,1'-oxybis- 110-98-5 EPA-HQ-OPPT-2019-0123 Initiated
Propanol, oxybis- 25265-71-8 EPA-HQ-OPPT-2019-0124 Initiated
Tetracosane, 2,6,10,15,19,23-hexamethyl- 111-01-3 EPA-HQ-OPPT-2019-0125 Initiated
*Status is listed as either:
  • Initiated – The first step of the prioritization process, and the chemical is currently undergoing a screening level review of reasonably available information to information its priority designation;
  • Proposed – The second step of the prioritization process, when EPA proposes a chemical’s designation as either high or low priority for risk evaluation; or
  • High/Low - The final step of the prioritization process. This chemical has been designated as high or low priority for risk evaluation.