Glyphosate (Gly) is one of the most widely used herbicide globally for weed control, and it has been detected in different aquatic ecosystems adjacent to intensive agricultural areas. In addition to emerging chemicals, organisms are simultaneously exposed to many environmental stressors. Rising water temperatures associated with global climate change represent the main concern for worldwide scientists and politicians. In the present study, the Mediterranean mussel (Mytilus galloprovincialis) was selected as the main European species in aquaculture production. Moreover, due to its exceptional nutritional value, it is commonly included in human diet. Increasing water temperatures may negatively affect the quality of the mussels measured by the fatty acid composition (FAs). Alteration in FAs is a sensitive early warning bio-indicator of stress, and can be considered a valuable biomarker in assessing the effects of environmental stressors on aquatic organisms. So, the main goals of this study were to determine the FAs composition and the related lipid nutritional quality indices (LNQI) in M. galloprovincialis collected from a mussel farm in the central Mediterranean Sea.
They were exposed for 4 days at 1 mg/L Gly at 20°C and at 28°C in 10 L tanks with 10 mussels each.
The results indicate that both rising temperature and Gly exposure affected the FAs composition and LNQI Mussel always exhibited a dominance of saturated (SFA) and polyunsaturated (PUFA). Also, omega-3 PUFAs (n-3), eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) showed a decrease according to temperature and Gly effect. All LNQI indicated a decline in lipid quality of M. galloprovincialis under these stressors.
This study highlights the importance of FAs as valuable biomarkers to predict the impacts of combined stressors on nutritional quality of M. galloprovincialis.