Premium
Responses of Daphnia magna to pulsed exposures of arsenic
Author(s) -
Hoang Tham C.,
Gallagher Jeffrey S.,
Klaine Stephen J.
Publication year - 2007
Publication title -
environmental toxicology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.813
H-Index - 77
eISSN - 1522-7278
pISSN - 1520-4081
DOI - 10.1002/tox.20242
Subject(s) - daphnia magna , arsenic , exposure duration , bioassay , toxicology , ecotoxicology , toxicity , biology , environmental chemistry , daphnia , arsenic toxicity , cladocera , reproduction , branchiopoda , chemistry , zoology , ecology , crustacean , organic chemistry
Research on the toxicity of arsenic has focused on sublethal effects that do not provide sufficient information for risk estimation. While most studies have focused on organism response to constant arsenic exposures, organisms in nature are exposed to fluctuating As concentrations. Consequently, results obtained from standardized bioassays with constant exposures may not adequately characterize risk to indigenous biota. This research was designed to characterize the response of Daphnia magna to fluctuating arsenic exposures during 21‐day experiments. At concentrations ≥3000 μg/L As, 21‐day pulsed exposure mortality increased as a function of exposure concentration and duration. In addition, 21‐day pulsed exposure mortality increased with increasing recovery time. Pulsed As exposure did not affect the growth of D. magna over 21 days. Twenty‐one day accumulative reproduction of D. magna was only affected by pulsed exposures of high As concentration and long durations. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 308–317, 2007.