Structuring Catalyst LVEs For Success Amid The Backlog

A catalyst used in small quantities in a well-controlled industrial application would seem to be the perfect candidate for a Low Volume Exemption (LVE) notification. In fact, in certain regions, such as the European Union (EU) and Canada, no premarket notification is required for substances manufactured or imported below certain tonnage limits (e.g., one metric tonne in the EU). But in the United States under the Toxic Substances Control Act (TSCA), there is no de minimis quantity and the U.S. Environmental Protection Agency (EPA) will conduct a rigorous review and risk assessment for even minute quantities of a catalyst used at industrial sites. Contrary to messages from detractors, LVEs go through the same review process as premanufacture notices (PMN) and must clear a higher bar — EPA must conclude that the LVE “will not present” unreasonable risk to be granted. A poorly supported LVE submission often increases the time needed for EPA’s review and the chance of EPA denying the LVE, which can set commercial deadlines back many months, at a minimum.

Catalysts are used to increase the rate of a reaction without being consumed themselves. Many catalysts include a metal with one or more ligands. It is not uncommon for EPA to identify significant toxicity concerns for human health or the environment for catalysts, ligands, or degradation products thereof. In addition to hazards associated with degradation products, EPA may also identify the metal in a catalyst as a persistent, bioaccumulative, and toxic (PBT) substance. Notifiers should be aware that TSCA does not permit LVEs for per- and polyfluoroalkyl substances (PFAS) or PBT substances.

In other cases, EPA may conclude that it has insufficient hazard information to complete a risk assessment due to the novelty of the catalysts, ligands, or degradation products. If EPA concludes that it has insufficient hazard information, the hazard is viewed by EPA as being infinitely high, meaning that exposure or release in any quantity results in denial of the LVE.

So, what can be done?

A thorough, well-structured LVE for a catalyst can employ the following strategies:

• Hazard Review: While EPA assesses hazards during its review of the LVE, notifiers are encouraged to prepare and submit a thorough hazard assessment that considers the catalysts, metabolites, degradation products, and known impurities for both health and aquatic toxicity endpoints. These data, for the substances themselves or suitable analogs, can help avoid an “insufficient hazard information” conclusion or avoid EPA identifying a PBT concern.

• No Dust: In any new chemical submission that includes solids transfer, EPA predicts significant dust exposure using conservative assumptions and models.Eliminating solids handling (e.g., by manufacturing or importing and processing only liquid solutions) can eliminate concerns EPA has for workers and the general population possibly exposed to dust. Alternatively, engineering controls (e.g., enclosed transfers) can be employed to transfer solids dust-free.

• Low or No Release: If an LVE is not bound to a certain production volume, EPA will assess the notification at 10,000 kg/year (the maximum allowed under an LVE). Binding to a relatively low production volume will minimize release estimates and reduce the opportunity for unreasonable risk. Alternatively, binding to “no predictable or purposeful releases” to water can be an effective strategy for obtaining an LVE grant, if your supply chain can accommodate this restriction.

• Exchange Letter: If the notifier is distributing the LVE substance to customers that must implement certain restrictions (e.g., no release to water), EPA can require that the notifier exchange a letter with customers to grant the LVE. This letter memorializes the basis for EPA granting the LVE and informs the customer of its obligation to abide by the specified restriction.

LVEs hold many advantages over PMNs, including a shortened review period and a lower submission fee, but, more importantly, LVEs can be crafted — in most instances — to address preemptively concerns EPA is likely to raise helping notifiers achieve timely grants and allowing prompt commercialization. Additionally, EPA, in 2025, announced efforts to increase throughput of LVEs, to help clear backlogged cases, adding further tailwinds to this approval pathway. After an LVE is granted, a notifier may later submit an LVE Modification if restrictions of the LVE need to be modified. If a production volume higher than 10,000 kg/year is needed, a PMN may be submitted. While EPA does allow the simultaneous submission of an LVE with a PMN, EPA will accept a PMN after an LVE is granted, so an LVE can be an effective steppingstone to a PMN.