ACUTE TOXICITY OF SILVER TO SELECTED FRESHEATER INVERTEBRATES

Abstract

Silver is used in jewelry, silverware, coins, electroplating, .and photo­ graphic processes. It is a waste product in the manufacture of these products and processes. Also, metal mining and milling processes result in silver entering natural waters. Silver is one of the most toxic metals to freshwater organisms. Davies et - (J 9.78 )_ reported a maxi mum acceptable toxicant concentration (.MATC) for silver and rainbow trout {_Salmo gairdneri) to be 0.09-0.17 µg•L-1. Lima et ­ {19.82). reported silver 96 h LC501s for the flagfish (_Jordanella floridae)., fathead minnow (Pimephales promelas), and amphipod {_Gammarus pseudolimnaeus) at 9.. 2, 10..7, and 4.5 µg•L. -· 1, respecti.vel y. They also reported a 48 h LC50 for midge larvae (Janytarsus dissimilis) at 3,160 µg·L -1 . This study reports the results of static acute exposures to silver with a hydroid (Hydra sp.), a leech (Nephelopsis obscura) and a mayfly nymph {_Leptophlebia sp.).