These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Initial risk assessment for three beta-blockers found in the aquatic environment.
    Author: Cleuvers M.
    Journal: Chemosphere; 2005 Apr; 59(2):199-205. PubMed ID: 15722091.
    Abstract:
    Daphnia magna, Desmodesmus subspicatus and Lemna minor were used to determine the ecotoxicity of beta-blockers. Propranolol was the most toxic substance, with EC50s of 7.7 mg l-1 in the Daphnia test and 0.73 mg l-1 in the algal test. The toxicity of atenolol and metoprolol in the Daphnia test was very low, with EC50s of 313 and 438 mg l-1, respectively. In the algal test, metoprolol (EC50: 7.9 mg l-1) was more toxic than atenolol (EC50: 620 mg l-1). Lemna minor was the least sensitive species. All substances showed PEC/PNEC ratios <1, whereas propranolol with a ratio of 0.81 seems to be the most relevant substance and I recommend to perform chronic biotests to refine the estimate of the environmental risk. Taking bioconcentration factors (BCF) into account, resulting internal effect concentrations (IEC) differ only slightly, which means that the differences in the EC50 depend mainly on the diverse logP levels causing narcosis via disruption of membrane integrity. Predictions of toxicity using ECOSAR were close to the empirically measured data. Mixture toxicity of the three compounds could be predicted accurately using the concept of concentration addition.
    [Abstract] [Full Text] [Related] [New Search]