Richard Denison, Ph.D., is a Lead Senior Scientist.
[See UPDATE in brackets below.]
The Trump Environmental Protection Agency (EPA) has just released drafts of two more chemical risk evaluations it has conducted under the Toxic Substances Control Act (TSCA). One is for the likely human carcinogen and neurotoxicant 1,4-dioxane, which contaminates public water systems serving more than 7 million Americans in 27 states at levels exceeding the level EPA has traditionally (until now) aimed to meet for general population exposures. The other is for the flame retardant hexabromocyclododecane, or HBCD, a persistent, bioaccumulative and toxic (PBT) chemical – toxic to human development and highly acutely and chronically toxic to aquatic organisms – that has been banned or heavily restricted in most of the rest of the developed world.
As might have been expected of the Trump EPA, the draft risk evaluations wholly exonerate HBCD and largely do so for 1,4-dioxane. Especially in the latter case, EPA achieves its improbable finding through quite a sleight of hand: EPA simply excludes most exposures to the chemical from the scope of its risk evaluation.[pullquote]Trump EPA political appointees have repeatedly argued that the agency needs to be doing a better job at “risk communication.” I guess we now know what that means.[/pullquote]
Once finalized, EPA’s determinations that these chemicals “do not present an unreasonable risk” will mean it has no obligation or authority to impose any restrictions on their manufacture, processing, distribution, use, recycling or disposal.
We will be looking at these documents more closely in the very limited time EPA has provided for the public to review and comment on them. But I want to draw attention right off the bat to a telling aspect of how the Trump EPA has presented its risk determination for 1,4-dioxane.
EPA’s webpage and factsheet for its 1,4-dioxane risk evaluation both summarize the conclusions using the following text:
- No unreasonable risks to occupational non-users. EPA found no unreasonable risks to workers in the general area of 1,4-dioxane use but not directly in contact with the chemical.
- Unreasonable risks to workers in certain circumstances. These initial determinations are based on a draft assessment of the reasonably available information and are not EPA’s final determinations on whether this chemical presents unreasonable risks under the conditions of use. The Agency will use feedback received from the public and peer review processes to inform the final risk evaluations.
- No unreasonable risk to the environment. For all the conditions of use included in the draft risk evaluation, EPA found no unreasonable risks to the environment from 1,4-dioxane.
Note the dramatic contrast between the wording of the conclusions where EPA says it did not find any risks (the first and third bullets) versus those where it says it did (the second bullet). In the former case, EPA pulls no punches, stating unequivocally that “EPA found no unreasonable risks.”
Now look again at the text in the second bullet:
These initial determinations are based on a draft assessment of the reasonably available information and are not EPA’s final determinations on whether this chemical presents unreasonable risks under the conditions of use. The Agency will use feedback received from the public and peer review processes to inform the final risk evaluations.
While elsewhere EPA more generally indicates it may refine its draft conclusions based on feedback, all of the text in that second bullet that I’ve italicized applies equally to the conclusions in the first and third bullets. So why does EPA use it to caveat only the one “positive” risk finding?
[UPDATE: The press release EPA issued on June 28 to announce the release of the drafts (not available online) also used equivocal language (emphasis added): “The data in the draft risk evaluation for 1,4-dioxane does show there could be unreasonable risks to workers in certain circumstances.]
This same stark contrast can be seen in the draft risk evaluation itself. In the risk determination section of the introduction (pp. 21-22), EPA states pithily and unequivocally that:
- “there are no risks of 1,4-dioxane to the aquatic pathways” (p. 21);
- “EPA does not find unreasonable risks to the health of occupational non-users” (p. 21); and
- for one major subset of conditions of use, “EPA finds that the aforementioned conditions of use do not present an unreasonable risk of injury to health” (p. 22).
However, for the other subset of conditions of use where EPA does indicate worker risks, here is the heavily caveated and tentative language EPA uses to state that finding (p. 22):
EPA assessed inhalation and/or dermal exposure scenarios that resulted in MOEs [margins of exposure] and/or cancer risk estimates that indicate risks relevant to the respective benchmarks. EPA considered those risk estimates; confidence in the data used in the risk estimates and uncertainties associated with the risk estimates; and relevant risk-related factors described above and has preliminarily concluded that the aforementioned conditions of use present an unreasonable risk of injury to health, as set forth in the risk determination section of this draft risk evaluation. This draft document’s preliminarily [sic] determination of unreasonable risk does not mean that this is EPA’s final conclusion. EPA will consider further input through scientific and public review.
What kinds of signals does this contrasting language send to stakeholders? For industry stakeholders, it plays up EPA’s tentativeness over any findings of risk and invites them to engage in the public comment process because doing so could well lead EPA to change its mind.
For other stakeholders, such as those in the labor, health and environmental communities, who believe this chemical likely does present significant risks for the general population, consumers and the environment as well as workers, EPA’s language signals, in short: “Comment if you want, but we have already made up our minds.”
Trump EPA political appointees have repeatedly argued that the agency needs to be doing a better job at “risk communication.” I guess we now know what that means.