Technical Bulletin No. 0171: Bioassay of Spent Sulfite Liquor, Lignosulfate, and Their Decomposition Products

The attached Technical Bulletin was first issued in 1964. It reported on a National Council for Stream Improvement aquatic biology project at the Institute of Paper Chemistry which explored the tolerance of fish food organisms, daphnia and the burrowing May-fly nymph to spent sulphite liquor and calcium ligno-sulfonate. Similar bioassays were made for fish using the common shiner as the test organism. It was concluded from these studies at that time that the concentrations of SSL and calcium lignosulfonate, to which mortality of these organisms could be attributed, were far in excess of those found in surface waters under normal conditions of mill discharge.