On September 21, 2016, the U.S. Environmental Protection Agency (EPA) Office of Pollution Prevention and Toxics (OPPT) announced its regulatory determinations for a batch of Microbial Commercial Activity Notices (MCAN) and premanufacture notices (PMN).

The announcement by EPA consisted of ten new microorganisms submitted as MCANs and seven new chemicals submitted as PMNs. All microorganisms and chemical substances were determined “not likely to present an unreasonable risk” (per Toxic Substances Control Act (TSCA) Section 5(a)(3)(C)). This determination was based in all cases on the low hazard of the microorganism or the chemical substance. The microorganisms and chemical substances are:


  • J-16-0010: Generic: Saccharomyces cerevisiae modified;
  • J-16-0011, J-16-0012, J-16-0013, J-16-0014, J-16-0015, and J-16-0016: Generic: Biofuel Producing Organism;
  • J-16-0017: Generic: Saccharomyces cerevisiae modified;
  • J-16-0018: Generic: Saccharomyces cerevisiae modified; and
  • J-16-0006: Generic: Trichoderma reesei modified.


  • P-16-0343 and P-16-0344: Generic: Modified urethane polymer;
  • P-16-0391: Generic: Polyester polyol polymer with aliphatic isocyanate and phenol derivates;
  • P-16-0366: Generic: Blocked polyisocyanate;
  • P-16-0373: Generic: Tris(alkyloxyphenyl)triazine compounds;
  • P-16-0466: Generic: 2,5-Furandione, telomer with ethenylbenzene and (alkylethyl)benzene, amides with polyethylene-polypropylene glycol aminoalkyl Me ether, alkali salts; and
  • P-16-0348: Generic: Polypentaerythritol, mixed esters with linear and branched monoacids.

In both types of submissions, the EPA reports are facilitated by the use of templates. The footnotes in the template describe the approach and methodology followed to identify uses and to determine persistence, bioaccumulation, human health hazard, and environmental hazard.

The MCAN template includes three footnotes that describe: (1) identification of “known” and “reasonably foreseen” uses; (2) criteria for human health hazard; and (3) criteria for ecological hazard.

The PMN template includes seven footnotes that describe: (1) identification of “known” and “reasonably foreseen” uses; (2) criteria for persistence; (3) criteria for bioaccumulation; (4) criteria for human health hazard ranking; (5) criteria for ecological hazard ranking; (6) link to the TSCA New Chemicals Program Chemical Categories; and (7) link to the Organization for Economic Cooperation and Development’s (OECD) 2014 Guidance on Grouping of Chemicals. The OECD link and a link to the Sustainable Futures Manual within footnote 5 are obsolete.

The ecological hazard ranking criteria are consistent with OPPT’s past practice. The human health ranking criteria departs from practice by using a single descriptor for all endpoints. Other approaches that EPA has used for several years utilize criteria that address specific end points. Examples include the ChAMP (Chemical Assessment and Management Program) Methodology and the section 8(e) program.

Risk Determinations

For the MCANs, the “unlikely to present” determination is based on the human health hazard criteria identified in the template for human health hazard: “a microorganism is considered to have low human health hazard if it is not known to be a frank human pathogen that causes disease in healthy adults, and/or animal studies have demonstrated a lack of pathogenicity or toxicity”; and “a microorganism is considered to be of low ecological hazard if it is not known to be an animal or plant pathogen, and the genetic modifications do not impart pathogenic or toxigenic traits, and the introduced genetic material does not provide a selective growth advantage in outcompeting indigenous microbial communities in the environment.”

For the chemical substances, estimates indicated that the majority of these chemicals were persistent or very persistent and bioaccumulation potential was low for all chemicals. Human health hazard was determined by using a combination of physicochemical properties and structural analogs. Ecological hazard determinations utilized analog information and, as appropriate, estimates made by the Ecological Structure Activity Relationships (ECOSAR) Class Program. Exposure estimates were not conducted based of the low hazard concern from which followed the “not likely to present an unreasonable risk” determination.