A--Separation and analysis of manufactured nanomaterials in environmental samples

The U.S. Environmental Protection Agency (U.S. EPA) has a requirement for the separation and analysis of manufactured nanomaterials in environmental samples. The National Exposure Research Laboratory (NERL) of the EPA Office of Research and Development (ORD) is developing methodologies to assess occurrence data. Occurrence data is necessary for developing risk assessments whereby risk from a particular exposure is considered and estimated as to its impact on ecosystems and ultimately human health. As a part of this effort, the Environmental Sciences Division-Environmental Chemistry Branch (ESD-ECB) of NERL is developing specific approaches to develop standardized methods where analytical gaps are identified for nanomaterials, especially the most commercially used nano-silver. The main goal of this research project is the separation and characterization of the manufactured nano-silver from complex environmental media and from naturally occurring nanoparticles that ma y be present and cause interferences, e.g. SiO2, Fe2O3, or TiO2. This action is being pursued on a sole source basis for the following reason. Construction, testing, and, if required, modification of a spinning disc apparatus that is capable of the separation of silver nanoparticles from environmental media is a unique capability existing at the University of Nevada, Las Vegas (UNLV). UNLV has considerable expertise in using selective surface sorption to separate particles. Separation from environmental matrices is critical for this effort so as to provide analyses of manufactured and engineered nano-silver. In order to trace and verify that separation is achieved, the separation studies will include the use of radioactive gamma ray emitting silver atoms created by neutron capture and determined by a gamma ray detector. This operation takes advantage of a unique combination of separation capabilities, combined with use of radioactive tracers present at UNLV. The nanoparticle nature of the separated silver particles will be verified by use of a transmission electron microscope (TEM) or a scanning electron microscope (SEM) to measure the silver nanoparticle dimensions. Once a successful separation technique is proven, it shall be applied to environmental matrices selected from surfaces, ground water, wastewater, plants, fish tissues, biosolids, sediments, and soils. To the best of our knowledge this combination of required expertise appears to be unique to UNLV, especially the use of the spinning disc apparatus, which may have the surface of the disc modified by adding surface coatings, combined with the use of the radiolabeled silver tracer. NAICS Code 541620 applies with a small business size standard of 500 employees. The intent of this notice is to determine if any other sources(s) exist, and therefore, no solicitation (RFQ) is available. Consequently, any response failing to demonstrate the aforementioned capabilities and instead choosing to merely submit a routine letter requesting a copy of the RFQ will be ignored. Interested parties who can meet the above requirements may submit written qualification statements, fully explaining their capability no later than 15 days after the date of this publication. Submit response to the U.S. EPA, Attn: John Southerland Jr (MC-E105-02), RTP Procurement Operations Division, Research Triangle Park, NC 27711.