Heavy metal toxicity to Lemna minor: studies on the time dependence of growth inhibition and the recovery after exposure

Drost, W; Matzke, M; Backhaus, T

HERO ID

161930

Reference Type

Journal Article

Year

2007

Language

English

PMID

17157350

HERO ID 161930
In Press No
Year 2007
Title Heavy metal toxicity to Lemna minor: studies on the time dependence of growth inhibition and the recovery after exposure
Authors Drost, W; Matzke, M; Backhaus, T
Journal Chemosphere
Volume 67
Issue 1
Page Numbers 36-43
Abstract Environmental concentrations of toxic substances are not necessarily constant but fluctuate over time. Periods of intense exposure might be followed by episodes with a relatively low or no exposure, in principle allowing exposed organisms to recover from toxic injury. The growth reproduction assay with the limnic vascular plant Lemna minor allows for convenient studies on the time dependence of the aquatic toxicity of chemicals. Here we report on a study with four priority metals (Zn, Cu, Ni, Cd). Aims of the study were to determine the impact of the exposure duration on the observed toxicities and to determine the potential for recovery. The bioconcentrations of the test metals were recorded during the exposure in order to analyse, whether changes in the internal concentrations are a governing factor for the dynamics of toxicity. After an exposure of 7 days, Cd and Cu showed the highest toxicity to Lemna (EC50's of 1.9 and 9.7 mu M respectively), while Ni and Zn had a slightly lower toxicity (EC50's of 56.3 and 46.1 mu M respectively). Additionally, Zn showed a severely delayed toxicity and the exposed plants did not recover even 7 days after the exposure had ended. This is in sharp contrast to the other test metals, for which a considerable recovery was observed. These results indicate the necessity to more thoroughly consider the dynamics of toxicity, instead of recording toxic effects only after a constant exposure over a fixed time.
Doi 10.1016/j.chemosphere.2006.10.018
Pmid 17157350
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Article Subject Terms: Toxicity tests; Pollution effects; Aquatic; plants; Cadmium; Bioaccumulation; Growth rate; Heavy metals; Toxicity; Metals; Chemicals; Reproduction; Growth; Injuries; Water Pollution; Effects; Exposure; Duckweed; Zinc; Testing Procedures; Assay; Article; Taxonomic Terms: Lemna minor; Lemna
Is Qa No