Adverse effects posed by phthalates in marine mussels: Metabolism of phase I and II, antioxidant defense and peroxidative damage.

Nowadays, there has been increased concern about the presence of phthalates in the environment, due to their toxic potential. This group of compounds includes dibutyl phthalate (DBP), widely used as a plasticizer and as a fixing or stabilizing agent in various consumer and industrial products. This study evaluated the effects of DBP on Mytilus sp. mussels exposed to five concentrations of DBP (0.375μg/L; 0.75μg/L; 1.5μg/L; 3μg/L; 6μg/L), defined based on values reported for estuarine ecosystems. Subsequently, ecotoxicological parameters were evaluated in the gills and hepatopancreas of the exposed animals, such as the activities of the CYP3A4 isoenzyme, glutathione S-transferases (GSTs), catalase (CAT), and glutathione peroxidase (GPx). The extent of lipid peroxidation was also evaluated. The data obtained for these parameters did not show significant changes. The absence of responses may be related to several factors, such as exposure duration, exposure intensity, and effective defense mechanisms on the part of the organisms. Although these data may indicate a reduced biological risk under the conditions tested, it is important to consider that phthalates are widely distributed in the environment and chronic, cumulative exposure, or exposure in combination with other pollutants may potentiate adverse effects. This work reinforces the importance of integrated ecotoxicological approaches that consider the variability of responses between species, tissues, and environmental conditions in order to enable a holistic assessment of the ecological risks associated with phthalates and support effective environmental monitoring and management strategies.