Letizia Marsili | University of Siena / Università di Siena (original) (raw)
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Papers by Letizia Marsili
SETAC Europe 28th Annual Meeting. Responsible and Innovative Research for Environmental Quality, 2018
Frontiers in Marine Science, 2022
Among killer whale forms, type C is a fish-eating form and is the most common in the Ross Sea. In... more Among killer whale forms, type C is a fish-eating form and is the most common in the Ross Sea. In the austral summer 2015, a study was conducted to evaluate the toxicological hazard these marine mammals face in the Antarctic ecosystem. Seven biopsy samples were collected from adult individuals (five males and two females) in the surroundings of the Italian Research Station Mario Zucchelli, Terra Nova Bay, by remote dart sampling from the pack ice. The accumulation levels of persistent organic pollutants (POPs) such as legacy (DDTs, PCBs, and HCB) and emerging (PBDEs and DP) were measured. Moreover, the protein expression of cytochrome P450 (CYP1A1 and 2B) and the mRNA level variations of the peroxisome proliferator-activated receptors α and γ (PPARα-γ) and the estrogen receptor α (ERα), aryl hydrocarbon receptor (AhR), and Cyp1a were evaluated. Twenty PCB congeners, six DDTs, HCB, three HCHs, and fourteen brominated BDEs and DP-syn and anti-isomers were analyzed on freeze-dried blub...
The aim of this study was to develop and validate a suite of sensitive responses (biomarkers) for... more The aim of this study was to develop and validate a suite of sensitive responses (biomarkers) for monitoring conservation status and human impact in Posidonia oceanica meadows. Analytical methods were developed for NADPH cytochrome c reductase, ethoxicoumarin-o-deetilase (ECOD), guaiacol peroxidase (GPOX) and superoxide dismutase (SOD) assays. Western blot and a preliminary proteomic approach using 2-DE were also proposed as biomarkers. These techniques were initially tested on samples of posidonia experimentally exposed to various contaminants. Once validated, this approach was applied to Posidonia in a field study. Specimens of the seagrass were collected at four sites with potential different human impact along northern Tyrrenian coast. The results showed that reductase activity was significally induced in the various sampling areas compared to the reference site. GPOX and SOD showed a similar trend; the highest activities were measured in samples collected in front of a chlor-alkali plant and close to a river estuary. Analysis of residues (heavy metals, PAHs and OCs) measured on leaves showed differences between sites. A significant correlation was found between levels of Hg and GPOX and levels of Cr, Al and As and reductase activity. These results validated the potential use of the biomarkers approach on Posidonia for the assessment of ecotoxicological impact on the coastal environment
This paper focuses on three main aspects related to the impact of macro and micro-plastics on Med... more This paper focuses on three main aspects related to the impact of macro and micro-plastics on Mediterranean large vertebrates: a) the direct and indirect effects of micro- and macro-plastics exposure and related contaminants, on large marine vertebrates; b) the case studies of three large marine vertebrates in the Mediterranean, the fin whale (Balaenoptera physalus), the basking shark (Cetorhinus maximus) and a reptile, the loggerhead sea turtle (Caretta caretta); c) future developments on how to detect the toxicological effects in these species
Among killer whale forms, the type C is a fish eating form and the most common in the Ross Sea. I... more Among killer whale forms, the type C is a fish eating form and the most common in the Ross Sea. In the austral summer 2015 a study to evaluate the toxicological hazard C type killer whale faces in the Antarctic ecosystem was conducted in Terra Nova Bay. Seven biopsy samples were collected from adult specimens (5 males and 2 females) in the surroundings of the Italian research station Mario Zucchelli by means of remote dart sampling from the pack ice.The accumulation levels of persistent organic pollutants (POPs), including legacy (DDTs, PCBs, HCB) and emerging POPs (PBDEs) were measured. Moreover, the protein expression of cythocrome P450 (CYP1A and 2B) and the mRNA level variations of the peroxisome proliferator-activated receptors α and γ (PPARαγ) and the Estrogen Receptor α (ERα) were evaluated. PPARs are ligand-dependent nuclear receptors involved in lipid homeostasis, inflammation and adipogenesis, and ERα is involved in the estrogen pathways and induced by estrogen-like exogenous compounds such as OCs and PBDEs. PCBs (twenty-one ortho PCB congeners), DDTs, HCB and PBDEs (fourteen congeners from tri- to deca-substituted) were analyzed on freeze-dried blubber biopsy samples by GC-qMS. The protein expression was evaluated by Western Blot and the mRNA levels were quantified by quantitative Real-Time PCR. The average abundance pattern for the contaminants was DDTs>PCBs>HCB>PBDEs. Contaminant levels resulted to be lower when compared to existing data from Antarctic type C killer whales from Ross Sea (McMurdo Sound) and those reported for the fish-eating resident or offshore killer whales, or feeding at higher trophic levels. Both protein and gene expression biomarker responses were correlated to contaminant levels to evaluate the biological responses to POPs. A comprehensive assessment of the ecotoxicological status of Ross Sea killer whale will be undertaken by considering the satellite tracking and feeding ecology data gained on the same samples
The 4th International Whale Shark Conference, 2016
Background The impact that pollutants have on whale sharks (Rhincodon typus) is a question that r... more Background The impact that pollutants have on whale sharks (Rhincodon typus) is a question that remains largely unexplored. Whale sharks (WSs) are known to aggregate seasonally in different areas in the Gulf of California. Although this species is protected in Mexico since 2001, habitats for most of these aggregations are not protected. Out of the 7 localities were they aggregate, 3 are protected whereas the other 4 need to have some protection. Urban and touristic developments are major threats to their habitats because they lead to mangrove and estuary damage, both being important areas for their food resources. Moreover, due to poor fishery regulations, whale sharks often die as by-catch in fishing nets. The growth of tourism in the area of La Paz and Los Cabos represents an increase in maritime traffic and, thereby an increase in the number of collisions of WSs with boats. Finally, the increasing human activity in WS grounds is the cause of chemical pollution from urban waste wa...
SETAC Europe 28th Annual Meeting. Responsible and Innovative Research for Environmental Quality, 2018
Frontiers in Marine Science, 2022
Among killer whale forms, type C is a fish-eating form and is the most common in the Ross Sea. In... more Among killer whale forms, type C is a fish-eating form and is the most common in the Ross Sea. In the austral summer 2015, a study was conducted to evaluate the toxicological hazard these marine mammals face in the Antarctic ecosystem. Seven biopsy samples were collected from adult individuals (five males and two females) in the surroundings of the Italian Research Station Mario Zucchelli, Terra Nova Bay, by remote dart sampling from the pack ice. The accumulation levels of persistent organic pollutants (POPs) such as legacy (DDTs, PCBs, and HCB) and emerging (PBDEs and DP) were measured. Moreover, the protein expression of cytochrome P450 (CYP1A1 and 2B) and the mRNA level variations of the peroxisome proliferator-activated receptors α and γ (PPARα-γ) and the estrogen receptor α (ERα), aryl hydrocarbon receptor (AhR), and Cyp1a were evaluated. Twenty PCB congeners, six DDTs, HCB, three HCHs, and fourteen brominated BDEs and DP-syn and anti-isomers were analyzed on freeze-dried blub...
The aim of this study was to develop and validate a suite of sensitive responses (biomarkers) for... more The aim of this study was to develop and validate a suite of sensitive responses (biomarkers) for monitoring conservation status and human impact in Posidonia oceanica meadows. Analytical methods were developed for NADPH cytochrome c reductase, ethoxicoumarin-o-deetilase (ECOD), guaiacol peroxidase (GPOX) and superoxide dismutase (SOD) assays. Western blot and a preliminary proteomic approach using 2-DE were also proposed as biomarkers. These techniques were initially tested on samples of posidonia experimentally exposed to various contaminants. Once validated, this approach was applied to Posidonia in a field study. Specimens of the seagrass were collected at four sites with potential different human impact along northern Tyrrenian coast. The results showed that reductase activity was significally induced in the various sampling areas compared to the reference site. GPOX and SOD showed a similar trend; the highest activities were measured in samples collected in front of a chlor-alkali plant and close to a river estuary. Analysis of residues (heavy metals, PAHs and OCs) measured on leaves showed differences between sites. A significant correlation was found between levels of Hg and GPOX and levels of Cr, Al and As and reductase activity. These results validated the potential use of the biomarkers approach on Posidonia for the assessment of ecotoxicological impact on the coastal environment
This paper focuses on three main aspects related to the impact of macro and micro-plastics on Med... more This paper focuses on three main aspects related to the impact of macro and micro-plastics on Mediterranean large vertebrates: a) the direct and indirect effects of micro- and macro-plastics exposure and related contaminants, on large marine vertebrates; b) the case studies of three large marine vertebrates in the Mediterranean, the fin whale (Balaenoptera physalus), the basking shark (Cetorhinus maximus) and a reptile, the loggerhead sea turtle (Caretta caretta); c) future developments on how to detect the toxicological effects in these species
Among killer whale forms, the type C is a fish eating form and the most common in the Ross Sea. I... more Among killer whale forms, the type C is a fish eating form and the most common in the Ross Sea. In the austral summer 2015 a study to evaluate the toxicological hazard C type killer whale faces in the Antarctic ecosystem was conducted in Terra Nova Bay. Seven biopsy samples were collected from adult specimens (5 males and 2 females) in the surroundings of the Italian research station Mario Zucchelli by means of remote dart sampling from the pack ice.The accumulation levels of persistent organic pollutants (POPs), including legacy (DDTs, PCBs, HCB) and emerging POPs (PBDEs) were measured. Moreover, the protein expression of cythocrome P450 (CYP1A and 2B) and the mRNA level variations of the peroxisome proliferator-activated receptors α and γ (PPARαγ) and the Estrogen Receptor α (ERα) were evaluated. PPARs are ligand-dependent nuclear receptors involved in lipid homeostasis, inflammation and adipogenesis, and ERα is involved in the estrogen pathways and induced by estrogen-like exogenous compounds such as OCs and PBDEs. PCBs (twenty-one ortho PCB congeners), DDTs, HCB and PBDEs (fourteen congeners from tri- to deca-substituted) were analyzed on freeze-dried blubber biopsy samples by GC-qMS. The protein expression was evaluated by Western Blot and the mRNA levels were quantified by quantitative Real-Time PCR. The average abundance pattern for the contaminants was DDTs>PCBs>HCB>PBDEs. Contaminant levels resulted to be lower when compared to existing data from Antarctic type C killer whales from Ross Sea (McMurdo Sound) and those reported for the fish-eating resident or offshore killer whales, or feeding at higher trophic levels. Both protein and gene expression biomarker responses were correlated to contaminant levels to evaluate the biological responses to POPs. A comprehensive assessment of the ecotoxicological status of Ross Sea killer whale will be undertaken by considering the satellite tracking and feeding ecology data gained on the same samples
The 4th International Whale Shark Conference, 2016
Background The impact that pollutants have on whale sharks (Rhincodon typus) is a question that r... more Background The impact that pollutants have on whale sharks (Rhincodon typus) is a question that remains largely unexplored. Whale sharks (WSs) are known to aggregate seasonally in different areas in the Gulf of California. Although this species is protected in Mexico since 2001, habitats for most of these aggregations are not protected. Out of the 7 localities were they aggregate, 3 are protected whereas the other 4 need to have some protection. Urban and touristic developments are major threats to their habitats because they lead to mangrove and estuary damage, both being important areas for their food resources. Moreover, due to poor fishery regulations, whale sharks often die as by-catch in fishing nets. The growth of tourism in the area of La Paz and Los Cabos represents an increase in maritime traffic and, thereby an increase in the number of collisions of WSs with boats. Finally, the increasing human activity in WS grounds is the cause of chemical pollution from urban waste wa...