A proposal of method to evaluate the quality of marine waters: Optimisation of 7 days bioassays using Dicentrarchus labrax (L.) juveniles

Abstract

European sea bass juveniles were exposed to cadmium chloride (CdCl₂·2½H₂O) as reference toxicant. The effects have been evaluated on the survival rates of the fish throughout 7 days. The LC50 (mg/L of cadmium ions) were: 6.17 mg/L (95% confidence interval: 5.44–6.99) after 24 h and 3.43 mg/L (95% confidence interval: 2.87–4.07) after 7 days exposure. This method could be used as a standard procedure to be conducted in short-term tests for estimating the chronic toxicity of marine waters. The high availability of this species at every stage of the productive cycle gives the opportunity to employ Dicentrarchus labrax as test organism for defining environmental quality standards.

Keywords:

• Dicentrarchus labrax
• Test organism
• Bioassays
• Ecotoxicology