Apparatus and Procedure for Measuring Sublethal Toxicity of Wastewater Discharges.

摘要

A screening test to detect the presence of sublethal toxicity was developed. Changes in respiration rates were used as the criteria for toxicity to aquatic life in wastewater effluents. An aquatic respirometry system and a data acquisition system were designed,constructed,and tested. Respiration rates are determined by electronically measuring the current used by a demand-type electrolysis cell which generates oxygen by the electrolysis of water. The oxygen concentrations within the respirometers vary less than plus or minus 0.05mg/l;measurements of oxygen consumption exceed 98percent accuracy. A holding facility producing large numbers of animals suitable for bioassay testing was also designed and constructed. Data are presented showing the growth rates of rainbow trout (Salmo gairdneri) and brook trout (Salvelinus fontinalis) in this holding facility. The routine respiration rates of these species measured in the respirometry system are compared with rates reported in the literature. (Modified author abstract)