BIOAVAILABILITY AND TOXICITY OF SILVER TO BENTHIC ORGANISMS IN FRESHWATER SYSTEMS CONTAINING SEDIMENTS OF DIFFERENT CHARACTERISTICS - PROGRESS REPORT (Quarters I and II)

Abstract

Since the proposal for this project was submitted in early August, 1996, and approved by the National Association of Photographic Manufacturers (NAPM) for study starting on October 1, 1997, several changes have been discussed with members of the scientific panel within NAPM and with other national experts on silver and other heavy metals. Daniel Call had an opportunity to present the planned research at a meeting of renowned environmental chemists and toxicologists in early September, 1996, who had convened for a meeting on the development of national criteria for chemicals in sediment at the EPA Laboratory in Duluth, MN. This meeting was attended by several EPA-Duluth staff, including Gary Ankley, David Mount, and Russell Erickson; Mary Reilly of EPA-Washington, D.C.; Richard Swartz of EPA­ Newport, OR; David Hansen and Walter Berry of EPA-Narragansett, RI; Dominic DiToro and Paul Paquin of HydroQual; and Herbert Allen of the University of Delaware. Based upon discussion following this presentation and a subsequent teleconference call that included Joe Gorsuch of Eastman Kodak Co., Dominic DiToro of HydroQual, Tom Purcell of NAPM, Dave Mount of EPA-Duluth, and David Hansen and Walter Berry of EPA-Narragansett, it was concluded that the most useful information to both the silver industry and the regulatory community would be achieved by modifying the Year I plan from that of the approved proposal. The major suggested changes were to focus on a single sediment, and to perform a definitive toxicity test with a single freshwater sediment, rather than to use the four-sediment matrix as originally proposed; and to increase the chemical analyses and resultant documentation of silver chemistry in this definitive test.

This progress report documents our efforts from October 1, 1996, through March 31, 1997. We presented ·our results to Joe Gorsuch and Ken Robillard in a half-day session on silver on March 26, 1997. Methods and results are presented by task.