Richard Denison, Ph.D., is a Senior Scientist.
[Part II of this post is available here.]
Word hit the street today that EPA intends to make public a "sanitized" version of a Consent Order it has negotiated with a producer of multiwalled carbon nanotubes (MWCNTs). [A link will be provided once available.] We obtained a copy of the Order, which has redacted all information claimed confidential by the company involved. What can we learn from this well-scrubbed Order?
The Order was triggered by EPA's review of a premanufacturing notification (PMN) – which, of course, is only required of companies producing the subset of nanomaterials EPA has decided to regard as "new." This is the first public glimpse, albeit limited, into both EPA's thinking and its regulatory approach to "new" nanomaterials.
EPA redacted the name of the company that has agreed to this Order – even though a simple Google search revealed that it almost certainly is Swan Chemical, Inc., of Lyndhurst, NJ. That's because the company recently issued a press release announcing the Order.
So what does the Order call for? The company is to:
- conduct a 90-day inhalation toxicity test in rats;
- supply EPA with a 1-gram sample of its MWCNTs and its Material Safety Data Sheet;
- submit certain characterization data within 6 months after commencing full manufacture;
- require its workers to wear protective gloves and clothing shown to be impermeable and NIOSH-approved respirators;
- use the substance only for a particular use, claimed confidential but generically identified as a "property modifier" in electronics and polymer composites; and
- provide the nanomaterial only to entities that agree to the same use restrictions and worker protection conditions.
Given recent evidence that MWCNTs can behave biologically rather like asbestos, such measures are more than called for.
But what's equally interesting are the details, including those that are missing from the sanitized Order because they were deemed confidential:
- The inhalation toxicity study doesn't need to be submitted before manufacture commences, but rather 14 weeks before either: a) manufacture reaches a level of [BLEEP] kilograms, or a period of [BLEEP] years and [BLEEP] months after manufacture passes, whichever comes first.
From this, it's not at all clear: a) why such details are secrets, and b) just how long it will be before the study is submitted.
- Adding to this mystery, the clock doesn't even start clicking on the time limit until two years after the Order is signed.
- The Order notes that no – zero, none, nada – test data were submitted with the company's PMN.
This is actually not unusual for PMNs that come in under the Toxic Substances Control Act (TSCA), since EPA cannot require development and submission of such data up front, even for conventional chemicals.
- Despite this lack of data, the Order states that EPA has determined that no significant environmental effects are expected. Given how little environmental data exist on nanomaterials in general, let alone this particular MWCNT, it's hard to imagine how EPA reached this conclusion.
- The Order does state that "EPA is unable to determine the potential for human health effects" from exposure to this nanomaterial, and hence that it "may present an unreasonable risk of injury to human health."
Presumably this is because of those recent findings that MWCNTs may act like asbestos.
So, to summarize these last two points: Only if EPA already has evidence of a potential effect can it conclude that it is unable to determine whether there is an effect and call for testing. If EPA doesn't have evidence of a potential effect – even if it has no data at all – it's ready to conclude that no significant effects are expected. Welcome to life under TSCA!
Other very interesting tidbits:
The Order encourages the company to sign up for the in-depth phase of EPA's voluntary Nanoscale Materials Stewardship Program (NMSP), stating that if it does, EPA may waive the Order's requirement to conduct an inhalation toxicity test. We can only wish that EPA gets something more than a non-binding commitment from the company to do some testing before vacating the Order!
Assuming the Order stays in place, if EPA finds the results of the required study to be "equivocal," the company can expand production beyond the production limit. (I won't even discuss the perverse incentive this provision could create.) Only if the company wants to get out from under the Order's other requirements (the use restriction or the worker protection provisions) need it reconduct the study.
What if the test results are invalid?
The Order appears to state that, if EPA finds the test data to be invalid, the company cannot expand production. But there's a catch: If there's not enough time to reconduct the study and submit it 14 weeks before exceeding the production limit, then the company can go ahead and exceed the limit as long as it submits the study "within a reasonable period of time." The company can also exceed the production limit if it challenges EPA's determination that the data are invalid in writing.
If the company decides the test data are invalid before submitting them to EPA, as long as it informs EPA of this determination, EPA can still decide to allow expanded production. As before, if EPA does decide to require the company to reconduct the study, but there's not enough time to reconduct and submit it 14 weeks before exceeding the production limit, then the company can go ahead and exceed the limit as long as it submits the study "within a reasonable period of time."
What if the test results show significant risk?
The Order states that if EPA determines that the data are valid and unequivocal and indicate the nanomaterial "will or may present an unreasonable risk," EPA may but is not required to notify the company, and may but is not required to impose additional conditions. If EPA does issue such a notice, the company must either comply with the new conditions or cease production, use and distribution. But again there's a catch: If the company challenges EPA's determination in writing, it can continue these activities while the dispute is resolved.
All these allowances for the very type of nanomaterial that is #1 on just about everyone's concern list.
[UPDATE: It should be noted that the above allowances are actually fairly standard practice for new chemical consent orders and are not limited to those issued for nanomaterials; indeed, EPA has developed "boilerplates" for its consent orders that contain very similar language.]
I have been among those calling on EPA for greater transparency in how it assesses new nanomaterials. This is a step in the right direction in that regard. But I have to say that getting this glimpse at EPA's inner workings doesn't exactly bolster my confidence in what they're doing.