Unai Vicario | University of the Basque Country, Euskal Herriko Unibertsitatea (original) (raw)
Papers by Unai Vicario
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2012
Journal of Environmental Monitoring, 2011
In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, My... more In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, Mytilus galloprovincialis, were collected in 22 localities from Galicia and the Bay of Biscay (North Iberian peninsula) in July, and September 2003, April, July, and October 2004-2005 and April 2006. Lysosomal membrane stability (labilisation period, LP) and lysosomal structural changes (lysosomal volume density, Vv(L) and lysosomal surface-to-volume ratio, S/V(L)) were measured as general stress biomarkers. The most remarkable long-term effects after the POS were drastic changes in lysosomal size (lysosomal enlargement) and membrane stability (extremely low LP values) up to April-04. Later on, a recovery trend was envisaged all along the studied area after July-04, albeit membrane stability continued to be below 20 min throughout the studied period up to April-06, which indicates a "distress-to-moderate-stress" condition. Lysosomal Response Index (LRI) revealed that environmental stress was more marked in Galicia than in the Bay of Biscay, mainly in the first sampling year, although a "moderate-to-high-stress" condition persisted until July-05. Overall, although lysosomal size returned to reference values, membrane stability was not fully recovered indicating a stress situation throughout the studied period.
Concerns are increasing about the effects that the growing presence of engineered nanoparticles (... more Concerns are increasing about the effects that the growing presence of engineered nanoparticles (NPs) in the aquatic environment could produce to biota. In this context, zebrafish (Danio rerio) has been shown to be a useful model to study the biological effects of NPs. The aim of this work was to study the effects produced by CuO, Ag and CdS NPs (0.01 mg/L) in adult zebrafish in comparison to those produced by the dissolved metals. Samples were collected at 3 and 21 days of exposure and at 6 months post--exposure. By the end of the exposure, relevant mortality was only observed in fish exposed to both ionic (67%) and NP (71%) forms of Cd. According to the lysosomal membrane stability (LMS) test all tested NPs significantly impaired general health status. Genotoxic effects measured using the micronucleus test in erythrocytes were not observed. Histopathological (HP) analysis performed after 21 days of exposure revealed altered structure of gill lamellae in all treated animals, while no relevant alterations were detected in liver. After 21 days of exposure, metal bioaccumulation was detected by autometallography in intestine cells of all exposed fish, being specially apparent in silver exposed ones, and weaker in copper exposures. Accordingly increased metal content quantified in whole fish by ICP--AES. Overall our results indicate that zebrafish exposure to CuO, Ag and CdS NPs results in metal accumulation that leads to toxic effects, being LMS and HP alterations of gills sensitive parameters of NP exposure. CdS NPs resulted the most toxic, followed by Ag and CuO NPs.
Journal of Nanoparticle Research, 2014
Increasing use of nanomaterials is resulting in their release into the environment, making necess... more Increasing use of nanomaterials is resulting in their release into the environment, making necessary to determine the toxicity of these materials. With this aim, the effects of CuO, ZnO and TiO 2 nanoparticles (NPs) on zebrafish development were assessed in comparison with the effects caused by the ionic forms (for copper and zinc), bulk counterparts and the stabilizer used for rutile TiO 2 NPs. None of the NPs caused significant embryo mortality. CuO NPs were the most toxic affecting hatching and increasing malformation prevalence (C1 mg Cu/L), followed by ZnO NPs that affected hatching at C5 mg Zn/L and stabilized TiO 2 NPs that caused mortality and decreased hatching at 100 mg Ti/L. Exposure to the stabilizer alone provoked the same effect. Thus, toxicity of the TiO 2 NP suspension can be linked to the surfactant. For all the endpoints, the greatest effects were exerted by the ionic forms, followed by the NPs and finally by the bulk compounds. By autometallography, metal-bearing deposits were observed in embryos exposed to CuO and ZnO NPs, being more abundant in the case of embryos exposed to CuO NPs. The largest and most abundant metalbearing deposits were detected in embryos exposed to ionic copper. In conclusion, metal oxide NPs affected zebrafish development altering hatching and increasing the prevalence of malformations. Thus, the use and release of metal oxide NPs to the environment may pose a risk to aquatic organisms as a result of the toxicity caused by NPs themselves or by the additives used in their production.
Journal of Environmental Monitoring, 2011
In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, My... more In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, Mytilus galloprovincialis, were collected in 22 localities from Galicia and the Bay of Biscay (North Iberian peninsula) in July, and September 2003, April, July, and October 2004-2005 and April 2006. Lysosomal membrane stability (labilisation period, LP) and lysosomal structural changes (lysosomal volume density, Vv(L) and lysosomal surface-to-volume ratio, S/V(L)) were measured as general stress biomarkers. The most remarkable long-term effects after the POS were drastic changes in lysosomal size (lysosomal enlargement) and membrane stability (extremely low LP values) up to April-04. Later on, a recovery trend was envisaged all along the studied area after July-04, albeit membrane stability continued to be below 20 min throughout the studied period up to April-06, which indicates a "distress-to-moderate-stress" condition. Lysosomal Response Index (LRI) revealed that environmental stress was more marked in Galicia than in the Bay of Biscay, mainly in the first sampling year, although a "moderate-to-high-stress" condition persisted until July-05. Overall, although lysosomal size returned to reference values, membrane stability was not fully recovered indicating a stress situation throughout the studied period.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2012
Journal of Environmental Monitoring, 2011
In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, My... more In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, Mytilus galloprovincialis, were collected in 22 localities from Galicia and the Bay of Biscay (North Iberian peninsula) in July, and September 2003, April, July, and October 2004-2005 and April 2006. Lysosomal membrane stability (labilisation period, LP) and lysosomal structural changes (lysosomal volume density, Vv(L) and lysosomal surface-to-volume ratio, S/V(L)) were measured as general stress biomarkers. The most remarkable long-term effects after the POS were drastic changes in lysosomal size (lysosomal enlargement) and membrane stability (extremely low LP values) up to April-04. Later on, a recovery trend was envisaged all along the studied area after July-04, albeit membrane stability continued to be below 20 min throughout the studied period up to April-06, which indicates a "distress-to-moderate-stress" condition. Lysosomal Response Index (LRI) revealed that environmental stress was more marked in Galicia than in the Bay of Biscay, mainly in the first sampling year, although a "moderate-to-high-stress" condition persisted until July-05. Overall, although lysosomal size returned to reference values, membrane stability was not fully recovered indicating a stress situation throughout the studied period.
Concerns are increasing about the effects that the growing presence of engineered nanoparticles (... more Concerns are increasing about the effects that the growing presence of engineered nanoparticles (NPs) in the aquatic environment could produce to biota. In this context, zebrafish (Danio rerio) has been shown to be a useful model to study the biological effects of NPs. The aim of this work was to study the effects produced by CuO, Ag and CdS NPs (0.01 mg/L) in adult zebrafish in comparison to those produced by the dissolved metals. Samples were collected at 3 and 21 days of exposure and at 6 months post--exposure. By the end of the exposure, relevant mortality was only observed in fish exposed to both ionic (67%) and NP (71%) forms of Cd. According to the lysosomal membrane stability (LMS) test all tested NPs significantly impaired general health status. Genotoxic effects measured using the micronucleus test in erythrocytes were not observed. Histopathological (HP) analysis performed after 21 days of exposure revealed altered structure of gill lamellae in all treated animals, while no relevant alterations were detected in liver. After 21 days of exposure, metal bioaccumulation was detected by autometallography in intestine cells of all exposed fish, being specially apparent in silver exposed ones, and weaker in copper exposures. Accordingly increased metal content quantified in whole fish by ICP--AES. Overall our results indicate that zebrafish exposure to CuO, Ag and CdS NPs results in metal accumulation that leads to toxic effects, being LMS and HP alterations of gills sensitive parameters of NP exposure. CdS NPs resulted the most toxic, followed by Ag and CuO NPs.
Journal of Nanoparticle Research, 2014
Increasing use of nanomaterials is resulting in their release into the environment, making necess... more Increasing use of nanomaterials is resulting in their release into the environment, making necessary to determine the toxicity of these materials. With this aim, the effects of CuO, ZnO and TiO 2 nanoparticles (NPs) on zebrafish development were assessed in comparison with the effects caused by the ionic forms (for copper and zinc), bulk counterparts and the stabilizer used for rutile TiO 2 NPs. None of the NPs caused significant embryo mortality. CuO NPs were the most toxic affecting hatching and increasing malformation prevalence (C1 mg Cu/L), followed by ZnO NPs that affected hatching at C5 mg Zn/L and stabilized TiO 2 NPs that caused mortality and decreased hatching at 100 mg Ti/L. Exposure to the stabilizer alone provoked the same effect. Thus, toxicity of the TiO 2 NP suspension can be linked to the surfactant. For all the endpoints, the greatest effects were exerted by the ionic forms, followed by the NPs and finally by the bulk compounds. By autometallography, metal-bearing deposits were observed in embryos exposed to CuO and ZnO NPs, being more abundant in the case of embryos exposed to CuO NPs. The largest and most abundant metalbearing deposits were detected in embryos exposed to ionic copper. In conclusion, metal oxide NPs affected zebrafish development altering hatching and increasing the prevalence of malformations. Thus, the use and release of metal oxide NPs to the environment may pose a risk to aquatic organisms as a result of the toxicity caused by NPs themselves or by the additives used in their production.
Journal of Environmental Monitoring, 2011
In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, My... more In order to assess the long-term lysosomal responses to the Prestige oil spill (POS), mussels, Mytilus galloprovincialis, were collected in 22 localities from Galicia and the Bay of Biscay (North Iberian peninsula) in July, and September 2003, April, July, and October 2004-2005 and April 2006. Lysosomal membrane stability (labilisation period, LP) and lysosomal structural changes (lysosomal volume density, Vv(L) and lysosomal surface-to-volume ratio, S/V(L)) were measured as general stress biomarkers. The most remarkable long-term effects after the POS were drastic changes in lysosomal size (lysosomal enlargement) and membrane stability (extremely low LP values) up to April-04. Later on, a recovery trend was envisaged all along the studied area after July-04, albeit membrane stability continued to be below 20 min throughout the studied period up to April-06, which indicates a "distress-to-moderate-stress" condition. Lysosomal Response Index (LRI) revealed that environmental stress was more marked in Galicia than in the Bay of Biscay, mainly in the first sampling year, although a "moderate-to-high-stress" condition persisted until July-05. Overall, although lysosomal size returned to reference values, membrane stability was not fully recovered indicating a stress situation throughout the studied period.