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April 30, 2010

PPDC Discusses Nanotechnology and Pesticides

The ACTA Group

At yesterday’s U.S. Environmental Protection Agency’s (EPA) Pesticide Program Dialogue Committee (PPDC) meeting, William Jordan, Senior Policy Advisor, Office of Pesticide Programs (OPP), presented slides regarding nanotechnology and pesticides. Jordan briefly described how OPP is defining nanoscale materials and how the technology is being applied to the field of pesticides. His presentation described OPP’s recent consultation with EPA’s Scientific Advisory Panel (SAP) concerning nanosilver and other nanometal pesticide products, as well as other ongoing regulatory activity and future actions OPP intends to take. The background materials from the meeting are available online, and the slides are available online.

OPP’s working definition of nanomaterial is:

An ingredient that contains particles that have been intentionally produced to have at least one dimension that measures between approximately 1 and 100 nanometers.

Although nanomaterials occur naturally and can be produced unintentionally, Jordan noted that OPP’s working definition includes the phrase “intentionally produced,” and that those are the ones OPP intends to address. According to Jordan, there is at least one registered product that contains nanomaterials. Jordan stated that the registrant applied for a “me-too” registration and registered the product as a material preservative similar to other registered silver products. The product contains nanosilver, however, which the registrant did not disclose. OPP believes that there are likely other registered pesticides that contain nanomaterials, and OPP has sent out letters under Section 6(a)(2) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) to identify those products.

OPP asked SAP questions on the evaluation of hazard and exposure from nanosilver and other nanometal pesticide products. SAP met in November 2009, and released its recommendations in February 2010. Jordan summarized the SAP’s general message as OPP needs more data. To obtain more data, OPP is in the process of preparing a Federal Register notice on nanomaterials and pesticide products. The notice will announce a new interpretation of FIFRA Section 6(a)(2) regulations and propose a new policy in June 2010. The new interpretation will be that the presence of a nanoscale material is reportable under FIFRA Section 6(a)(2). This controversial interpretation would apply to already registered products, as well as products pending registration. The interpretation would constitute an interpretation of FIFRA and elaboration on the regulations governing reporting of unreasonable adverse effects. The basis for OPP’s decision to use the Section 6(a)(2) mechanism is that, according to OPP, there are studies that raise concerns that nanoscale materials may potentially affect human health and the environment adversely. The interpretation would place the burden of reporting on the registrants who are responsible under FIFRA for proving the safety/continued safety of their products.

In the same notice, EPA is expected also to memorialize OPP’s view that an active or inert ingredient would be considered “new” if it is a nanoscale material. The new policy would apply even when a non-nanoscale form of that same active or inert is already in a FIFRA-registered product.

Jordan also announced that OPP intends to respond in June 2010 to the International Center for Technology Assessment’s (ICTA) May 2008 petition. In its petition, ICTA urged EPA to regulate nanosilver products as pesticides. According to ICTA, even in its bulk form, “silver is extremely toxic to fish and other aquatic species” and at the nanoscale, nanosilver can be “many times more toxic.” ICTA points to “preliminary evidence” that nanosilver can exert effective antibacterial action at a considerably lower concentration than that of silver ions, suggesting that the antibacterial properties and toxicity of nanosilver are not explained only by its chemical composition and by the production of silver ions alone. ICTA asked EPA to take action on an estimated 600 unregistered nanosilver products marketed in the U.S.

Jordan noted the following activities in other EPA offices:

  • Office of Research and Development developing a Draft Case Study on nanosilver (expected in 2010); and
  • Office of Pollution Prevention and Toxics developing the following rules under the Toxic Substances Control Act:
    • Significant New Use Rule — Intended to address nanoforms of existing chemicals;
    • Section 8(a) Rule — Would obtain existing data on current nanomaterials; and
    • Section 4 Test Rule — Likely at the end of 2010.