Effect of age on acute toxicity of cadmium, copper, nickel, and zinc in individual-metal exposures to Daphnia magna neonates.

ABSTRACT: In previous studies, variability was high among replicate acute cadmium (Cd) Daphnia magna lethality tests (e.g., >10-fold range of median effect concentrations [EC50s]), less among zinc (Zn) tests, and relatively low for copper (Cu) and nickel (Ni) tests. Although the US Environmental Protection Agency's (USEPA's) protocol includes starting toxicity tests with neonates less than 24 h old, the authors hypothesized that age-related differences in sensitivity to metals might occur even within that relatively narrow age range. Daphnia magna neonates were collected during 3 age windows (0-4 h, 10-14 h, and 20-24 h old) and immediately exposed to each of the 4 metals for 48 h using the standard USEPA protocol. In repeated sets of tests during different weeks, the Cd EC50 of the youngest neonate

SUBMITTER: Traudt EM 

PROVIDER: S-EPMC5764767 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature