Exploring the Impact of Contaminants of Emerging Concern on Fish and Invertebrates Physiology in the Mediterranean Sea

Simple Summary Consumption and excessive use of substances or items that are taken for granted in our daily lives such as personal care products, plastic objects, and medicines inevitably lead to their release into marine and freshwater systems with, unfortunately, potentially devastating consequences over time. For this reason, it is of crucial importance that the scientific community, as well as society, is aware of the environmental problems linked mainly to the release of contaminants into the sea. In this context, the Mediterranean Sea is a special biodiversity hotspot of marine fauna and flora. Nevertheless, it is becoming a source of concern due to the presence of emerging pollutants. In the present paper, the specific focus on the catshark Scyliorhinus canicula, as a vertebrate species, and on the Mediterranean mussel Mytilus galloprovincialis, as an invertebrate, lies in their ability to provide appropriate information about the health conditions of their surrounding environment. The studies reported on this topic show that it is rather evident that entire aquatic ecosystems suffer from anthropogenic pollution. Therefore, this review aims to collect and demonstrate its effects on the environment and organisms' health. In this historical context, the Mediterranean Sea faces an increasing threat from emerging pollutants such as pharmaceuticals, personal care products, heavy metals, pesticides and microplastics, which pose a serious risk to the environment and human health. In this regard, aquatic invertebrates and fish are particularly vulnerable to the toxic effects of these pollutants, and several species have been identified as bio-indicators for their detection. Among these, bivalve molluscs and elasmobranchs are now widely used as bio-indicators to accurately assess the effects of contaminants. The study focuses on the catshark Scyliorhinus canicular and on the Mediterranean mussel Mytilus galloprovincialis. The first one is a useful indicator of localised contamination levels due to its exposure to pollutants that accumulate on the seabed. Moreover, it has a high trophic position and plays an important role in the Mediterranean Sea ecosystem. The bivalve mollusc Mytilus galloprovincialis, on the other hand, being a filter-feeding organism, can acquire and bioaccumulate foreign particles present in its environment. Additionally, because it is also a species of commercial interest, it has a direct impact on human health. In conclusion, the increasing presence of emerging pollutants in the Mediterranean Sea is a serious issue that requires immediate attention. Bivalve molluscs and elasmobranchs are two examples of bio-indicators that must be used to precisely determine the effects of these pollutants on the marine ecosystem and human health.