Aerospace & Electronics Industry Representatives Express Concerns About TSCA Substances

Aerospace & Electronics Industry Representatives Express Concerns About TSCA Substances

In March 2019, the U.S. Environmental Protection Agency (EPA) selected 40 substances to be evaluated and prioritized in accordance with the process outlined by the amended Toxic Substances Control Act (TSCA). The list was divided into two groups, with 20 potentially high priority substances and 20 potentially low priority substances. High priority substances were defined as those that, without considering costs or other non-risk factors, pose an unreasonable risk of harm to the public, environment and/or vulnerable subpopulations.

In June 2019, the 20 high priority substances underwent an initial public consultation process, which gave companies that rely on the substances the opportunity to provide information that could aid in risk evaluation.

Aerospace Industry Concerns

During the initial consultation, the U.S. Aerospace Industries Association (AIA), which consists of 340 organizations representing the aerospace and defense sector, requested that reasonable substitutes for eight substances be made available before the EPA slates them as high priority under the TSCA.

The AIA cited potential unintended consequences for the industry as the basis for their request. The substances, including chlorinated solvents, halogenated flame retardants and phthalates, are used in a range of complex applications, where finding substitutions with the same or superior quality is not always feasible. Therefore, restricting the use of these substances could result in business continuity disruptions for aerospace companies.

Although the high-priority list has not been finalized, the EPA may not be able to change the list created in March 2019 due to the TSCA’s required implementation timeline.


The Eight Substances

SubstanceCAS Number
Example Aerospace Use
75-34-3Heat resistant adhesive
p-dichlorobenzene106-46-7Component of automotive engine oils
di-isobutyl phthalate (DIBP)84-69-5Casting sealant
dicyclohexyl phthalate (DCHP)84-61-7Plasticizer
tris(2-chloroethyl) phosphate (TCEP)115-96-8Plasticizer and viscosity regulator with flame-retarding properties
1,3-butadiene106-99-0Thermal adhesive
ethylene dibromide (EDB)106-93-4Additive in aviation gasoline

Learn what collecting Full Material Disclosures can do for your company in our eBook, Full Material Disclosures: Building Resilience With Data.

Electronics Industry Concerns

A secondary consultation period is currently open until November 21, 2019. Recently, IPC, the Association Connecting Electronics Industries — a trade association representing the electronics industry — launched an advocacy campaign to collate comments from industry actors.

To gain a comprehensive understanding of the potential business disruptions that could result from substance restrictions, the IPC is asking companies in the electronics supply chain to provide detailed information regarding their use of substances slated to become high-priority. They have asked companies to consider the following questions in the formation of their comments:

  • Did the EPA accurately identify this chemical substance’s use based on your knowledge of electronics manufacturing and production processes?
  • What function does the chemical perform in the process or the product?
  • What is the chemical’s criticality to the process and the product?
  • How would you describe the scenario of use for the chemical substance, including potential human or environmental exposure?


High Priority Substances Identified in Electronics

SubstanceCAS NumberExample Electronics Use
Tris(2-chloroethyl) Phosphate (TCEP)115-96-8Flame retardant
4,4'-(1-Methylethylidene)bis[2,6-dibromophenol] (TBBPA)79-94-7Flame retardant
Triphenyl Phosphate (TPP)115-86-6Flame retardant
Phthalic Anhydride85-44-9--
Dibutyl Phthalate84-74-2Thermal adhesive
Di-Ethylhexyl Phthalate117-81-7Plasticizer
Butyl Benzyl Phthalate (BBP)85-68-7Adhesive ingredient


Determining if These Substances Are in Your Products

Assent helps companies streamline the collection and management of supply chain data to support risk mitigation. To learn more about how Assent can help you identify the use of these substances or any restricted substance in your supply chain, contact