Pharmaceutical and personal care products (PPCPs) containing persistent and potentially hazardous substances have garnered attention for their ubiquitous presence in natural environments. This study investigated the impact of polyethylene glycol (PEG), a common PPCP component, on Mytilus galloprovincialis. Mussels were subjected to two PEG concentrations (E1: 0.1 mg/L and E2: 10 mg/L) over 14 days. Oxidative stress markers in both gills and digestive glands were evaluated; cytotoxicity assays were performed on haemolymph and digestive gland cells. Additionally, cell volume regulation (RVD assay) was investigated to assess physiological PEG-induced alterations. In the gills, PEG reduced superoxide dismutase (SOD) activity and increased lipid peroxidation (LPO) at E1. In the digestive gland, only LPO was influenced, while SOD activity and oxidatively modified proteins (OMPs) were unaltered. A significant decrease in cell viability was observed, particularly at E2. Additionally, the RVD assay revealed disruptions in the cells subjected to E2. These findings underscore the effects of PEG exposure on M. galloprovincialis. They are open to further investigations to clarify the environmental implications of PPCPs and the possibility of exploring safer alternatives.

Personal Care Products (PCPs) have been one of the most studied chemicals in the last twenty years since they were identified as pseudo-persistent pollutants by the European Union in the early 2000s. The accumulation of PCPs in the aquatic environment and their effects on non-target species make it necessary to find new, less harmful, substances. Polyethylene glycol (PEGs) and polyvinyl alcohol (PVAs) are two polymers that have increased their presence in the composition of PCPs in recent years, but little is known about the effect of their accumulation in the environment on non-target species. Through embryotoxicity tests on two common models of aquatic organisms (Danio rerio and Xenopus laevis), this work aims to increase the knowledge of PEGs and PVAs' effects on non-target species. Animals were exposed to the pollutant for 96 h. The main embryotoxicity endpoint (mortality, hatching, malformations, heartbeat rate) was recorded every 24 h. The most significant results were hatching delay in Danio rerio exposed to both chemicals, in malformations (oedema, body malformations, changes in pigmentation and deformations of spine and tail) in D. rerio and X. laevis and significant change in the heartbeat rate (decrease or increase in the rate) in both animals for all chemicals tested.

Benzisothiazolinone (BIT) is a preservative and antimicrobial agent widely used in various household and industrial products. It is readily detectable in pesticides, polishes, printing inks and detergents. This extensive use is reflected in a vast amount of this compound in the environment, which may cause toxic effects in organisms that come in contact with it. In light of the aforementioned context, this work aims to investigate the potential cellular and physiological impact on aquatic organisms through in vitro tests, utilising haemocytes and digestive gland (DG) cells derived from the Mediterranean mussel (Mytilus galloprovincialis). Two different concentrations (B1: 0.03 µg/L; B2: 0.3 µg/L) were tested at two different times of exposure (T1: 1 h; T2: 3 h) to evaluate the viability of cells, the phagocytic activity (haemocytes), the regulation volume decrease (RVD on DG cells) capability. Moreover, the cytoprotective mechanisms related to oxidative stress and detoxification were evaluated through the expression analysis by qPCR of key genes involved in these pathways. The most significant results obtained from these tests were the reduction of viability of haemocytes at T2 of exposure to B2, a decrease of vitality in DG cells exposed to B1 during the T1, the significant alteration in the phagocytosis activity, the upregulation of Cu/ZnSOD gene, the inhibition of the CYPY1 gene expression and upregulation of the Heat shock protein 70 (Hsp70) gene following the BIT exposure. These findings provide a valuable foundation for further investigation, offering insights into the potential impact of BIT on aquatic communities.

A high percentage of the broad spectrum of contaminants in aquatic environments is represented by personal care products (PCPs). Polyvinyl alcohol (PVA) is contained in the formulation of many of these products. The extensive use of PVA caused the annual release of over 65.000 tons into the environment, constituting 1.2 % of particles in the Mediterranean Sea. For these reasons, the study aimed to investigate, for the first time in bivalve species, the possible cytotoxicity implications on non-target species, involved in the human food chain, caused by exposure to two different concentrations of PVA (PVA1: 0.1 mg L^-1 and PVA2: 10 mg L^-1). Following a fortnight of exposure, cell viability, regulation of cell volume decrease, oxidative stress, and biochemical parameters were evaluated. Moreover, the capability of the animal to produce byssal plaques was observed, representing a novelty for assessing the health status of mussels. The results showed a modification in the regulatory capacity of cell volume, particularly in those exposed to PVA2. An alteration in the superoxide dismutase activity (in PVA2) and in the levels of oxidatively modified proteins (PVA1 and PVA2) was detected in gills. A modification in the byssal plaque production following PVA exposure was also observed. These findings enrich the knowledge about the interaction between PVA and organisms, underscoring further research's need to elucidate the environmental implications.

The present study was prompted by an interest in understanding the potentially beneficial effects of bergamot peel extract on the cellular and physiological performance of appropriate aquatic model organisms subjected to daily environmental challenges, namely pollution. In this regard, specimens of Mytilus galloprovincialis were exposed to Sodium Lauryl Sulphate (0.01 mg/L), an extract of bergamot peels (5 mg/L), and a solution of the two (SLS + BRG), for fourteen days. The immune response was evaluated by assessing the ability of haemocyte cells to engulf foreign elements in conjunction with the gene expression of γ-actin, which plays a key role in cytoskeletal rearrangement. The physiological response was analysed through the analysis of cell volume regulation (RVD assay) in digestive gland cells and cytotoxicity assays (Neutral red and Trypan blue) on both cell populations, which exhibited notable alterations. In addition, the gene expression of genes involved in antioxidant activity, including Cu/ZnSOD, MnSOD, Hsp70, and CYP4Y1, was evaluated. Significant differences were observed between the control (CTR) and treated groups, with a consistent trend evident in the CTR and BRG groups, which exhibited a similar pattern to the SLS-treated groups. In contrast, the groups treated with the combination of the two compounds (SLS + BRG) demonstrated a recovery.