Programma della conferenza

Gadolinium (Gd), a rare earth element, has many technological and medical applications. Used in magnetic garnets, computer memories, and Magnetic Resonance Imaging (MRI), its safety has been questioned due to associations of the appearance of nephrogenic systemic fibrosis and calcium homeostasis disruption observed in the patients submitted to MRI. Studies also reveal its persistence in the body post-MRI and accumulation in the brain, bones, kidneys, and skin. Environmental concerns arise from its release into water bodies via hospital effluents and inefficient removal by wastewater treatment plants, reaching alarming levels in coastal and marine environments worldwide. Based on these assumptions this study aims to investigate the contamination of this emerging contaminant in 7 Italian areas along the Tyrrhenian, Ionian and Adriatic Seas. The bivalve Donax trunculus was selected and sampled as early warning sentinel, as well as sediment and water matrices. Lesina (Puglia) and Sibari (Calabria) were significantly the most contaminated sites in both sediment and D. trunculus matrices, confirming that the bivalves reflect environmental contamination. In addition, a 14-day indoor experiment with increasing Gd concentrations in D. trunculus was carried out to study the toxic effect of Gd and the oxidative stress caused by the contaminant. The results revealed that the detected concentrations of Gd induced oxidative stress in D. trunculus, affecting its metabolic capacity, antioxidant enzyme response, biotransformation mechanism, and lipid peroxidation. D. trunculus proved to be a suitable sentinel species for Gd analysis, showing a proportional accumulation of contaminants in its tissues. These findings highlight the risk of oxidative stress even at lower Gd concentrations, which are common in nature. As the use of Gd increases, environmental concentrations may rise, posing health risks to aquatic organisms and humans through biomagnification.

Among rapid ecotoxicological bioassays for screening soil quality, avoidance behaviour tests on gregarious edaphic species such as Porcellionides pruinosus are widely used. However, the effect of soil contamination on adaptive aggregation ability has not been investigated. The aim of this study was to develop a new ecotoxicological endpoint related to the disaggregation effect under infochemical disruption at the population level during an avoidance behaviour test. This new endpoint was evaluated using tire particles (TPs) and benzothiazole (BT) as preliminary physical and chemical substances. The disaggregation index (DI) and disaggregation groups (DG) are presented as measures of fragmentation of the population to quantify the effect of contaminants on aggregation behaviour. Aggregation disruption in a group of ten individuals is assessed alongside the sub-lethal avoidance test after a 48 hour exposure. The degree of disaggregation is measured by the number of subgroups formed. The DI and DG indices range from 0 to 1, representing the highest degree of aggregation and disaggregation, respectively, achieved at the end of the test. Our results show that all woodlice exposed to TPs and BT successfully passed the validation of the avoidance test, but failed to show gregarious behaviour in control soil, indicating fragmentation within the population, even if in uncontaminated soil. The disaggregation effects in woodlice occurred at higher concentrations than the avoidance ones, suggesting a possible effect on the adaptive capabilities of the population even in the control soil. These results suggest a combination of avoidance behaviour and disaggregation in individuals of P. pruinosus. Consideration of both aspects may provide more ecological, accurate and robust results for the evaluation of the stress induced by contaminant on natural population.

The aim of the ÆM-POLLY PNRR PRIN project is to develop and validate an integrated protocol as a tool to verify if the mitigation measures foreseen by the EU Green Deal for agricultural practices, are effective in halting and reversing the decline of wild pollinator biodiversity. This monitoring protocol will integrate endpoints in terms of presence, abundance and diversity of wild pollinator species with endpoints able to assess the state of health at the sub-individual, individual and population level. These endpoints are selected and designed to diagnose biological alterations in wild pollinators due to different pressures: chemical stress from pesticides, stress linked to climate changes, food and water deficiencies, habitat loss and diseases. Such an integrated approach using a set of biomarkers has never applied before to wild pollinators. The monitoring protocol is applied in 4 orchards and 4 vineyards characterised by the presence or absence of mitigation measures, and in 4 adjacent natural areas. Surveys for assessing pollinator diversity are performed once in spring and once in late summer. During this activity individuals of the most abundant/representative species are sampled for chemical (pesticide levels), morphological (body size and fluctuating asymmetry variations) and biomarker analysis (immune, reproductive, and nervous systems, oxidative stress, metabolism, detoxification processes and genotoxicity, energy mobilisation and feeding performance). From our project we expect to: 1) obtain a dataset of baseline biomarker values related to the health status of representative pollinator species; 2) assess the effectiveness of the mitigation measures by comparing the pollinator diversity and the biomarkers related to their health in two types of crops; 3) define a final integrated monitoring protocol to assess the health status of wild pollinators and their biodiversity; 4) develop user-friendly guidelines to assess the effectiveness of the different mitigation measures in different agroecosystems, to guide decisions and inform policies.