Following up on its final reporting and recordkeeping rule for manufactured (including imported) or processed nanoscale chemicals (January 12, 2017, FR), the EPA has issued a draft guidance document providing responses to questions the Agency has received from manufacturers and processors subject to the rule. The draft guidance is available for a 30-day public comment period ending June 15, 2017.
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Promulgated under Section 8(a) of the Toxic Substances Control Act (TSCA), the final rule requires onetime reporting of specific information about certain chemical substances that are 1–100 nanometers (nm) in at least one dimension. Information that must be reported includes specific chemical identity, production volume, methods of manufacture and processing, use, exposure and release information, and available health and safety information. Records of this information must also be kept for 3 years.
This draft guidance provides answers to 44 questions in five categories: what chemicals are reportable; who is required to report; what information is to be reported; when is reporting required; and general questions.
Unique and Novel Properties
Regarding which nanoscale chemicals must be reported, both the rule and the draft guidance address the key question of when a nanochemical is still subject to Section 8(a) even if the same chemical that does not consist of nanoscale particles has already been reported under the section. In the draft, the EPA provides the following guidance:
- A reportable chemical substance is a solid at 25°C and standard atmospheric pressure—which is manufactured or processed in a form where any particles, including aggregates and agglomerates, are in the size range of 1–100 nm in at least one dimension—and is manufactured or processed to exhibit unique and novel properties because of its size.
- Unique and novel properties means any size-dependent properties that vary from those associated with other forms or sizes of the same chemical substance. In other words, it is not sufficient that a chemical substance contains particles in the size range of 1–100 nm; it must also have a size-dependent property different from properties at sizes greater than 100 nm, and those properties are the reason that the chemical substance is manufactured or processed in that form or size.
- For example, intentionally manufacturing or processing nanoscale gold so that it exhibits a red or purple color instead of a yellow color is an example of a unique or novel optical property seen at the nanoscale. Such a change would likely result in changes of other properties, such as specific surface area, which can result in different health and safety impacts.
- A reportable chemical substance does not include a chemical substance that is manufactured or processed in a form where less than 1 percent of any particles, including aggregates and agglomerates, measured by weight are in the size range of 1–100 nm.
New Testing Not Required
Under EPA’s final rule, manufacturers and processors are not required to conduct testing or develop new information to meet Section 8(a) requirements for covered nanochemical substances. But they are required to report information that is known or reasonably ascertainable.
The draft guidance is here.