Industry Criticises EPA’s Review of TCE Alternatives in Proposed Ban

Industry groups say that the US EPA has not fulfilled its statutory requirement to assess the feasibility of alternatives in its proposed rule to ban trichloroethylene (TCE) in vapour degreasing applications.

The comments came in response to the second of two TSCA section 6 proposals to ban the solvent in certain uses, amid concerns at the adverse health effects it presents.

In its proposed vapour degreasing rule, the EPA says it has found a "wide variety of technically and economically feasible" alternatives. These include:

> drop-in solvents like methylene chloride, 1-bromopropane and tetrachloroethylene (perc);

> "designer solvents" like hydrofluoroolefin (HFO) or hydrofluorocarbon (HFC) and hydrofluoroether (HFE) solvent blends;

> aqueous cleaning systems; and

> other cleaning solvents, such as glycol ethers, siloxanes, Terpenes and soy-based cleaners.

But federal agency the Small Business Administration (SBA) said in comments that there are "significant issues associated with the possible alternatives, such as potential health hazards, availability for safe use, related (and prohibitive) equipment costs, low boiling points and uncertainty with cleaning effectiveness."

Drop-in replacement solvents, such as those proposed by the EPA, can be used in existing vapour degreasing systems with some modification, said the SBA. But these are all among the first ten substances subject to risk evaluation under the new TSCA, and may themselves become subject to regulation.

The "vast majority" of the cleaning substitutes, it said, do not clean as well as TCE, are more expensive and will require a "large capital investment for a cleaning process that is less efficacious".

SBA concerns with the non-drop in alternatives include that they:

> boil at a much lower temperature, resulting in increased worker exposure because they are harder to keep in the machine;

> require the addition of a flammable chlorinated derivative to be cleaned; and
are "ten times more expensive per pound", and significantly more product must be used.

In its comments, the American Chemistry Council (ACC) said that the EPA, "without any degree or evidentiary support", has claimed that aqueous water systems present less risk to workers and may seamlessly replace TCE systems.

But the trade group says these "are not adequate replacement systems", especially in areas with water supply constraints or facilities without room to install larger systems.

Dow Chemical subsidiary Safechem Europe said in comments that having investigated the impacts of the REACH authorisation process, it believes the effects of a ban would be "very negative and far-reaching".

For a "wide range" of applications in industrial parts cleaning operations, no feasible substitutes exist, says the company - and Echa’s scientific committees "accepted this conclusion".

Under the authorisation process, TCE was banned from the EU market in April 2016 - except for authorised uses. Safechem’s application for continued permitted use in vapour degreasing applications was backed by the committees - but only for seven years, after which time the company would have to reapply. It now awaits approval by the EU member states.

Call for alternatives assessment

The Chemical Users Coalition (CUC) – a cross-industry group of nine multinationals including Intel, Boeing, Honda and Procter & Gamble – urged the EPA to conduct an alternatives assessment "examining the comparative hazards, exposures, resource impacts and performance attributes of these substances".

It says the EPA has received "substantial information" showing how alternatives were impractical, incompatible with customer specifications and economically infeasible. But the agency has asked for more information on the alternatives.

It is not clear what information the agency needs, said the coalition, or how it considered the evidence already submitted to it, in making its determination that a TCE ban was not infeasible.

The coalition also said the EPA has not established a basis for why two years was a "reasonable" transition period.

But the Toxics Use Reduction Institute (Turi) at the University of Massachusetts, Lowell, said that experience with the state’s toxics reduction programme has shown that businesses can switch to aqueous or semi-aqueous solutions for many vapour degreasing applications – often, resulting in savings for the business.

And it said that in those cases where businesses think they need to continue using a solvent, safer ones are available, despite posing some concerns of their own.

Technical and laboratory assistance for testing safer alternatives can help businesses overcome the barriers to transition, it added.

Chemicals manufacturer 3M Corporation also lent its support to the proposed ban, saying in comments that its HFE-based technologies are "well positioned to ease the transition away from TCE".

Time-limited exemptions

In its proposed rule, the EPA said it will consider granting time-limited exemptions for specific conditions of use, provided:

> the use is essential and no technically or economically feasible safer alternative is available;

> that compliance with the ban would "significantly disrupt" the national economy, national security, or critical infrastructure; or

> that the TCE vapour degreasing application, as compared to reasonably available alternatives, provides a "substantial benefit" to public health, the environment or public safety.

The agency has requested comments to determine a process for receiving and evaluating petitions, and for issuing critical use exemption rules.

The ACC says the exemption process is essential for implementation of the new law, and the EPA therefore will "need to employ sufficient flexibility and transparency in its rulemaking".

But the CUC says it should define how a petition process could work before adopting a section 6 ban on TCE. And it should include exemptions in the rule itself in cases where it has already received "substantial information" about their necessity.

If the EPA decides to relegate these decisions to a future process, it "has a responsibility to define clearly what specific additional information, besides what it has already received ... would be needed to make a decision."

The CUC also wants a section 6 rule not to apply to a party that has filed a timely exemption request, while EPA deliberates on it.