On August 14, 2017, as the final Toxic Substances Control Act (TSCA) Section 8(a) information gathering rule on nanomaterials took effect, the U.S. Environmental Protection Agency (EPA) published “working guidance” intended to assist stakeholders in complying with the rule.  The working guidance notes that it “will not provide answers to all of the potential questions that will arise as manufacturers and processors seek to comply with the rule.  Commenters to the draft guidance asked several questions that would require more details or information before EPA could respond to their question.”  If the guidance does not answer questions about the rule, companies are directed to contact Jim Alwood, Chemical Control Division, Office of Pollution Prevention and Toxics, alwood.jim@epa.gov.  EPA states that it will answer questions on a case-by-case basis.  EPA intends to add further questions/answers and revisions to the guidance based on questions identified by persons who may be subject to the rule.  As reported in our January 11, 2017, blog item, the January 12, 2017, final rule establishes reporting and recordkeeping requirements for certain discrete forms of chemical substances that are manufactured or processed at the nanoscale.  Under the rule, manufacturers and processers, or persons who intend to manufacture or process these chemical substances must report certain information to EPA.  The information to be reported includes, insofar as known to or reasonably ascertainable by the person making the report, the specific chemical identity, production volume, methods of manufacture and processing, exposure and release information, and existing information concerning environmental and health effects.  Persons who manufacture or process a discrete form of a reportable chemical substance at any time during the three years prior to August 14, 2017, the effective date of the final rule, must report to EPA one year after the effective date of the final rule.  There is also a standing one-time reporting requirement for persons who intend to manufacture or process a discrete form of a reportable chemical substance on or after the effective date of the rule.  These persons must report to EPA at least 135 days before manufacture or processing of that discrete form.  More information regarding the final rule is available in our January 12, 2017, memorandum, “EPA Promulgates Final TSCA Reporting and Recordkeeping Rule for Nanoscale Materials.”