Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/10/2017
Publication Date: 9/5/2017
Citation: Straus, D.L. 2017. Copper sulfate toxicity to various fish: role of alkalinity/hardness [abstract]. 6th National Aquaculture Extension Conference, June 6-8, 2017, Boise, Idaho. p. 38.
Technical Abstract: Copper sulfate has been used in fisheries since the 1890’s. This compound is currently used to control parasites (mainly Ich) on fish and fungus (Saprolegnia) on fish eggs, and has also been used in the past to control columnaris on fish, although antibiotics are the common treatment now. In our lab’s efforts to gain an FDA-approval for copper sulfate, we are well-aware that there is a great deal of information on the toxicity of copper, especially in low-alkalinity waters; however, much of this information is fragmented, and a comprehensive guide of copper toxicity and safe concentrations in various water chemistries is not available. In addition, historical data does not always include alkalinity, which is crucial when determining toxicity. Therefore, our lab is in the process of developing this data across a wide range of species. Experiments have been initiated to observe the toxicity and safe levels of copper sulfate in 5 reconstituted waters, per APHA methods, on 13 species of fish; future studies may include bacteria, parasites and algae. The alkalinity of these synthetic waters ranges from 10 – 245 mg/L, and the hardness ranges from 10 – 320 mg/L. Data will include a 48h LC50 value for each species in each water, but more importantly, the No Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC). This information can be used to approximate safe treatment levels; however, application must be tailored to fit specific species and individual water quality and chemistry.