Evaluating Lanthanum-Induced Alterations in Manila Clam: An Integrated Method

Lanthanum (La), a rare earth element, has unique properties that make it valuable in various industries. Extraction activities pose environmental and health risks due to pollution, habitat disruption, and human exposure to hazardous chemicals. Animal models are needed to evaluate La effects on biological systems. We focused on the Manila clam, Ruditapes philippinarum, a common bivalve introduced in the Mediterranean Sea for commercial purposes. This study evaluates La-induced alterations in the Manila clam using an integrated method. Specimens were exposed to varying concentrations of lanthanum chloride, and subsequent changes in mucus secretion and microbial communities were observed. Inductively coupled plasma mass spectrometry analyses supported the bioaccumulation data. Histochemical and lectin-histochemical analyses revealed modifications in glycosaminoglycan composition and secretion patterns, indicating the clam's defensive response to La exposure. Bacterial counts in intervalvar water increased with higher La concentrations. These findings highlight the Manila clam's potential use as a bioindicator for La pollution and underline the importance of responsible management in La extraction to minimize environmental impact.