A New Toxicity Test Using the Freshwater Copepod Cyclops vernalis

Abstract

The cladocerans Ceriodaphnia dubia and Daphnia magna are widely used in environmental toxicity testing and the test methodologies for these species are well developed. However, copepods are a much more abundant contributor to zooplankton in many lakes, but they are not routinely used in toxicity tests. Therefore, we propose toxicity test methods for the freshwater copepod, Cyclops vernalis assessing effects on its survival and growth. A case study is presented in which the proposed test was performed with a range of concentrations of total dissolved solids (TDS) and used as part of a test battery to develop a site-specific water quality objective. C. vernalis was less sensitive to TDS compared to D. magna and C. dubia, but similarly sensitive to an alga, a diatom, a rotifer, a chironomid, and two fish species. No adverse effects were observed on survival or growth of C. vernalis at TDS concentrations up to 1500 mg/L.

Development of a total dissolved solids (TDS) chronic effects benchmark for a northern Canadian lake

“…All point estimates are presented as calculated TDS concentrations. Additional details are provided in Golder (); Chapman (, , ); Baker et al (); Marus et al (); and Chapman and Elphick (). Control performance met test acceptability criteria for all test methods, and test results were corrected for mean control responses.…”

“…The following tests were conducted. A brief summary of methodology is provided below; full details on methodology are provided in Golder (); Chapman (, , ); Baker et al (); Marus et al (); and, Chapman and Elphick (). Phytoplankton: 72‐h growth inhibition of the green alga Pseudokirchneriella subcapitata (Environment Canada ) and 120‐h growth inhibition of the diatom Navicula pelliculosa (ASTM ).…”

“…Green algae are found in Snap Lake. The diatom genus Navicula is found in Snap Lake. Zooplankton: 21‐d survival and reproduction of Daphnia magna (ASTM ), 48‐h rate of population increase of the rotifer, Brachionus calyciflorus (Snell and Moffat ; WDOE ; Zhang et al ), and 20‐d survival and growth of the copepod Cyclops vernalis (Chapman ; Marus et al ). The genera Daphnia , Brachionus , and Cyclops are all found in Snap Lake.…”

“…Site‐specific aquatic toxicity tests using a TDS mixture representative of Snap Lake conditions were conducted including novel tests (Baker et al ; Marus et al ). Based on these tests, a site‐specific benchmark, based on chronic effects, was developed for TDS and its major constituent ions in Snap Lake.…”

Evaluation of Catalytic Efficiency of Coriolopsis caperata DN Laccase to Decolorize and Detoxify RBBR Dye

“…For acute toxicity test, the freshwater copepod Cyclops was used according to the methodology developed by Marus et al [17]. The adult Cyclops was transferred to each set of tubes (ten per tube) with different concentrations of control dye (100, 50, 25, and 12.5 ppm) and enzyme-treated dye.…”