| Abstract |
Since the discovery of the specificity of xanthate for sulfide minerals, use of this reagent as a collector has increased to the point where the metallurgical industry in the United States alone uses about eight million pounds annually. In addition to xanthate, considerable quantities of other collectors, such as thiophosphate, thiocarbamate, carboxylate, sulfonate, and amine are also utilized. Billions of gallons of water are used in conjunction with these collectors, and although most flotation plants reclaim water used in processing, some water containing residual collector is lost to natural receiving waters. It is expected that these chemicals will exhibit toxic effects on aquatic life. Because of the quantity of collectors and water used in flotation processing, toxicity data are needed to determine the potential of these reagents for harming fish life. The objective of this study was to establish the 96-hour median lethal concentration (LC50-96) of selected collectors, namely ethylxanthate, isopropylxanthate, amylxanthate, diethyldithiophosphate, tallow amine, dibutyldithiophosphate, isopropylethylthiocarbamate, and others. |
