Field study of metal concentrations and biomarker responses in the neogastropod,Murex trunculus, from Bizerta Lagoon (Tunisia)
| Autor: | Patricia Aissa, Mohamed Dellali, Samia Gharbi-Bouraoui, M. Gnassia-Barelli, Michèle Roméo |
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| Rok vydání: | 2008 |
| Předmět: | |
| Zdroj: | Aquatic Living Resources. 21:213-220 |
| ISSN: | 1765-2952 0990-7440 |
| Popis: | This study aims to evaluate the health status of Bizerta lagoon using a sentinel species, the Neogastropod Murex trunculus. Trace metal concentrations (Cd, Cu and Zn) in the foot and digestive gland, and biomarkers such as acetylcholinesterase (AChE), catalase (CAT) and glutathione transferase (GST) activities in the digestive gland, were determined in samples collected at four sites at different periods of the year. One site, in the North of the lagoon, is influenced by urban and industrial waste waters. Another, to the south, is located at the outfall of Ichkeul Lake. A third site is one that may be impacted by eutrophication processes, and the last, in the center of lagoon, is considered as less polluted. Temperature and salinity were simultaneously measured during the mollusc samplings. They varied greatly, from 13.5 ◦ C and 30 psu in February to much higher values in summer-autumn: 30.7 ◦ C and 37 psu. Metal concentrations were always higher in the digestive gland than in the foot. In the digestive gland, the lowest Cd and Cu concentrations were found in the center of the lagoon (mean ± standard deviation: 9.35 ± 0.78 μ gC d g −1 and 84.5 ± 15.3 μ gC u g −1 ) and no significant Zn variations were noted (682 ± 38 μ gg −1 ) between sites. Metal concentrations in both types of tissue were higher in winter than in summer. AChE varied significantly among sites with high ac- tivities for individuals in the center of lagoon (15.4 ± 0.3 nmol min −1 mg −1 protein), whereas GST were low (12.2 ± 0.8 nmol min −1 mg −1 protein); CAT activities were low in this site 8.7 ± 0.5 μmol min −1 mg −1 protein. Season also had an influence on biomarkers, with low AChE in winter and rather low CAT and GST in summer. Principal component analysis showed that the center of lagoon can be considered as a reference site, whereas high chemical and biochemical responses were found in M. trunculus from other sites; particularly at the site which may be subject to eutrophication. |
| Databáze: | OpenAIRE |
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