Feedback from Diana Locke

Environmental Protection Agency

Posted on: March 30, 2007

Firstly, I want to commend you on a really high quality, comprehensive product. This should stand as the framework for The EPA, as well as the OECD Nanotechnology Workgroup, of which I am a member.

I do, however, have a few concerns that I believe should be addressed.

1. Page 11 Compensating assumptions.
   Without data, it is uncertain whether worker protection standards (respirators, air filters, protective clothing) will be sufficient to actually protect workers. Instituting WPS in the absence of toxicity data may not be protective enough if the equipment has not been tested for nano-scale compounds.
2. Page 25 Use of Default Values and Assumptions.
   Defaulting to data on bulk materials may potentially seriously underestimate toxicity and environmental fate. An example is gold, which in its bulk form is inert but in its nano-scale form is toxic. If one were to consider defaults to data on bulk compounds, uncertainty factors (10X) should be applied when conducting a risk assessment, such as those used in the EPA's Pesticide Program and Pre-manufacture Notice (PMN) program.

I was very pleased with Environmental Fate Data base set (page 42) and additional data, particularly the inclusion of the activated sludge test if there are releases to wastewater treatment. Overall, you have produced an outstanding framework and I look forward to seeing the next edition.