The ecosystems of Agadir Bay are periodically exposed to effluents containing untreated wastewater, introducing a complex and variable mixture of pollutants such as plastics, chemicals, hydrocarbons, heavy metals, and pharmaceutical residues. This study investigated the effects of these environmental stressors on neurotoxicity and oxidative stress responses in Monodonta lineata at two coastal sites, Cap Ghir and Anza. Among these, Cap Ghir served as the reference site. Sampling was conducted periodically at both locations to account for seasonal variations. To account for seasonal variations, sampling was conducted periodically at both locations. A multi-biomarker approach was employed to assess the seasonal dynamics of glutathione S-transferase (GST), catalase (CAT), malondialdehyde (MDA), and acetylcholinesterase (AChE) activities. Notably, CAT and AChE activity were higher during winter and spring 2022 at both sites, while elevated MDA and GST levels were observed in summer 2022 and winter 2023 at Cap Ghir and Anza, respectively. Multivariate statistical analyses were applied to identify the most reliable indicators of ecosystem health. The results revealed that seasonal fluctuations in biomarker responses were influenced by factors such as pollution gradients between sites, the intrinsic biological characteristics of M. lineata, and prevailing climatic conditions. Although this species has been understudied as a sentinel organism, our findings underscore its strong potential as a representative indicator of ecosystem health, highlighting the need for its greater inclusion in biomonitoring programs.
Elmchichi et al. (Sun,) studied this question.