Use of biomarkers to evaluate the effects of environmental stressors on Mytilus galloprovincialis sampled along the Moroccan coasts: Integrating biological and chemical data

•Identification of mussel biomarkers useful for marine biomonitoring studies.•Use of different approaches for biomarker data integration and interpretation.•Free use of the Mussel Expert System available by direct web connection.•Chemical data analysis by PCA helps to identify the causes of the biological effects.

A biomonitoring study using wild Mytilus galloprovincialis mussels sampled from six sites along the Moroccan coasts evaluated whether select biomarkers are suitable for identifying and quantifying pollution-induced stress syndrome in mussels. Lysosomal membrane stability was confirmed to be a highly sensitive biological parameter, and acetylcholinesterase activity was found a suitable biomarker of neurotoxicity. Metallothionein concentrations were in line with heavy metal concentrations detected in mussel tissues. However, malondialdehyde was not sensitive, suggesting the need for alternative biomarkers of oxidative stress. Three different approaches were used for biomarker and chemical data integration. The Integrated Biomarker Response (IBR) was suitable for classifying the stress response but did not allow to evaluate the level of stress in the organisms. The Mussel Expert System (MES) was suitable for ranking the biological effects of pollutants, also providing an indication of the evolution of the stress syndrome in the animals. Finally, the use of Principal Component Analysis (PCA) provided indication of the inorganic chemicals contributing to the detrimental biological effects.