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1.
Environ Monit Assess ; 196(6): 564, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773003

RESUMO

This study investigated the impact of micropollutants on fish health from Segredo hydroelectric reservoir (HRS) along the Iguaçu River, Southern Brazil, contaminated by urban, industrial, and agricultural activities. This is the first comprehensive study assessment in the river after the severe drought in the 2020s in three fish species from different trophic levels Astyanax spp. (water column depth/omnivorous), Hypostomus commersoni (demersal/herbivorous), and Pimelodus maculatus (demersal/omnivorous). Animals, water, and sediment samples were collected from three distinct sites within the reservoir: Floresta (upstream), Iratim (middle), and Station (downstream). The chemical analysis revealed elevated concentrations of metals (Al, Cu, Fe) and the metalloid As in water, or Cu, Zn, and As in sediment, surpassing Brazilian regulatory limits, while the organic pollutants as DDT, PAHs, PCBs, and PBDEs were found under the Brazilian regulatory limits. The metal bioaccumulation was higher in gills with no significant differences among sites. The species Astyanax spp. and H. commersoni displayed variations in hepatosomatic index (HSI) and P. maculatus in the condition factor index (K) between sites, while adverse effects due to micropollutants bioaccumulation were observed by biochemical, genotoxic, and histopathological biomarkers. The principal component analysis and integrated biomarker response highlighted the upstream site Floresta as particularly inhospitable for biota, with distinctions based on trophic level. Consequently, this multifaceted approach, encompassing both fish biomarkers and chemical analyses, furnishes valuable insights into the potential toxic repercussions of micropollutant exposure. These findings offer crucial data for guiding management and conservation endeavors in the Iguaçu River.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Brasil , Rios/química , Biomarcadores/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Metais/análise , Characidae , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Sedimentos Geológicos/química , Peixes/metabolismo
2.
Chemosphere ; 349: 140812, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38036225

RESUMO

Bioaccumulation studies in fish mark the initial phase of assessing the risk of chemical exposure to biota and human populations. The Iguaçu River boasting a diverse endemic ichthyofauna, is grappling with the repercussions of human activities. This study delved into the bioaccumulation of micropollutants, the early-warning effects on Rhamdia quelen and Oreochomis niloticus in the Segredo Reservoir (HRS) and the potential risk of human exposure. Two groups of caged fish in three sites of the reservoir were exposed during the autumn-winter and spring-summer, while a third group (O. niloticus) underwent a twelve-month exposure, and inorganic and organic chemicals analysis in water, sediment, and biota. Additionally, metallothionein expression and genotoxicity were employed as biomarkers. PAHs, PCBs, Al, Cu, Fe, and As in water and DDTs, Cu, Zn, and As in sediment surpassed the thresholds set by Brazilian regulations, where DDT exhibited bioaccumulation in muscle, alongside metals in liver, kidney, gills, and muscle tissues. R. quelen showed metallothionein expression whereas DNA damage and NMA frequencies were elevated in target organs and in brain and erythrocytes of O. niloticus during summer. In this species the DNA damage in liver was remarkable after twelve months. Target Hazard Quotients and Cancer Risk values shedding light on the vulnerability of both children and adults. The reservoir's conditions led to heightened sensitivity to micropollutants for R. quelen species. The data presented herein provides decision-makers with pertinent insights to facilitate effective management and conservation initiatives within the Iguaçu Basin.


Assuntos
Peixes-Gato , Poluentes Ambientais , Animais , Criança , Humanos , Rios , Brasil , Monitoramento Ambiental , Bioacumulação , Água , Metalotioneína
3.
Chemosphere ; 303(Pt 1): 134989, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35595115

RESUMO

The Iguaçu River basin presents high ecological importance due to its expressive endemic ichthyofauna rate, but chemical pollution may threat this biodiversity. Jordão River is one of the main tributaries of Iguaçu River and contribute to this pollution status, since it drains large agricultural areas receiving domestic and industrial effluents before flowing into the Iguaçu River. The objective of the current study was to evaluate the toxic effects of the Iguaçu, Jordão, and the combination of their waters to the embryo-larval phase of R. quelen, investigating the consequences to the population by means of mathematical modelling. R. quelen fertilized eggs were exposed for 96 h to water samples from Iguaçu River upstream (IR), Jordão River (JR), and downstream of both rivers (MR). The analysis of micropollutants in the water showed that JR presented the most complex mixture of substances and elements, followed by IR, while MR showed the lower number of micropollutants detected. Survival rate was not a sensitive endpoint, while the deformity indices were higher in individuals exposed to water from the three studied sites. Superoxide dismutase activity was increased in MR, while non-protein thiol levels were reduced in MR and JR showing the antioxidant mechanism activation. The mathematical modelling revealed that fish exposed to JR would lead to the greater population reduction (46.19%), followed by IR (40.48%) and MR (33.33%). Although the results showed toxicity in all studied sites, the JR site is the most impacted by micropollutants but decrease its toxicity after dilution with Iguaçu River.


Assuntos
Peixes-Gato , Poluentes Ambientais , Poluentes Químicos da Água , Animais , Brasil , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Rios/química , Água/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Rev Col Bras Cir ; 42(4): 215-9, 2015.
Artigo em Inglês, Português | MEDLINE | ID: mdl-26517795

RESUMO

OBJECTIVE: the study has the intention of evaluate the accuracy of computed tomography for the diagnosis of cervical lesions on penetrating neck trauma and also identify the most frequent mechanisms of trauma. Most injured structures, determine the age range and the most prevalent sex. METHODS: observational descriptive retrospective study executed by the systematic retrospective review of medical records of all patients victims of penetrating neck trauma that went through surgery and CT scans, admitted into Hospital do Trabalhador, between January 2009 and December 2013. RESULTS: the final sample was of 30 patients, 96.7% of the male sex, the median age was of 28 years old. Most patients suffered injuries by gun (56.7%) and 33,3% suffered stab wounds. The most stricken area of the neck was Zone II (77.8%) and the left side (55.2%). Regarding the structures injured, the CT showed 6.7% lesions on airways but the surgery showed 40% of damaged, with a value of p=0.002. As to damages of the esophagus and pharynx the CT detected 10% of lesions, while surgery found 30% of lesions, therefore with a significant value of p=0.013. As for the analysis the CT showed reliable. As for the analysis of vascular damage, the CT showed to be, in most cases, reliable to the findings during the surgical act. CONCLUSION: besides the great use of CT for the diagnosis of penetrating neck injuries we can say that this is an exam with low accuracy for the diagnosis of lesions of aerodigestive tract, therefore it is important a clinical correlation for a good diagnosis.as for the vascular lesions and of other structures, the CT had high sensibility and specificity, thus a good exam to be used in overall.


Assuntos
Lesões do Pescoço/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ferimentos Penetrantes/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Rev. Col. Bras. Cir ; 42(4): 215-219, July-Aug. 2015. tab
Artigo em Inglês | LILACS | ID: lil-763360

RESUMO

ABSTRACTObjective:the study has the intention of evaluate the accuracy of computed tomography for the diagnosis of cervical lesions on penetrating neck trauma and also identify the most frequent mechanisms of trauma. Most injured structures, determine the age range and the most prevalent sex.Methods: observational descriptive retrospective study executed by the systematic retrospective review of medical records of all patients victims of penetrating neck trauma that went through surgery and CT scans, admitted into Hospital do Trabalhador, between January 2009 and December 2013.Results:the final sample was of 30 patients, 96.7% of the male sex, the median age was of 28 years old. Most patients suffered injuries by gun (56.7%) and 33,3% suffered stab wounds. The most stricken area of the neck was Zone II (77.8%) and the left side (55.2%). Regarding the structures injured, the CT showed 6.7% lesions on airways but the surgery showed 40% of damaged, with a value of p=0.002. As to damages of the esophagus and pharynx the CT detected 10% of lesions, while surgery found 30% of lesions, therefore with a significant value of p=0.013. As for the analysis the CT showed reliable. As for the analysis of vascular damage, the CT showed to be, in most cases, reliable to the findings during the surgical act.Conclusion:besides the great use of CT for the diagnosis of penetrating neck injuries we can say that this is an exam with low accuracy for the diagnosis of lesions of aerodigestive tract, therefore it is important a clinical correlation for a good diagnosis.as for the vascular lesions and of other structures, the CT had high sensibility and specificity, thus a good exam to be used in overall.


RESUMOObjetivo:avaliar a acurácia da tomografia computadorizada no diagnóstico de lesões do trauma cervical penetrante.Métodos:estudo retrospectivo descritivo observacional realizado através da revisão de prontuários de todos os pacientes vítimas de trauma cervical penetrante que foram operados e submetidos à tomografia computadorizada no pré-operatório.Resultados:a amostra final compreendeu 30 pacientes, sendo 96,7% do sexo masculino e a mediana de idade foi 28 anos. A maioria dos pacientes sofreu ferimento por arma de fogo (FAF) em 56,7% dos casos e 33,3% foram ferimentos por arma branca (FAB). A zona do pescoço mais acometido foi a zona II (77,8%) e no lado esquerdo (55,2%). Em relação às estruturas lesadas, a tomografia computadorizada (TC) mostrou 6,7% de lesões em vias aéreas e durante a operação encontrou-se 40% de alterações (p=0,002). A tomografia computadorizada detectou 10% de leões do esôfago e faringe, durante a operação encontrou-se 30% de lesões (p=0,013). Já, para análise de danos vasculares, a TC se mostrou, na maioria dos casos, fidedigna aos achados durante o procedimento operatório.Conclusão:apesar do grande uso da tomografia computadorizada no diagnóstico de lesões cervicais penetrantes, pode-se afirmar que este é um exame com baixa acurácia no diagnóstico de lesões de trato aerodigestivo, sendo importante uma correlação clínica para um bom diagnóstico. Já para lesões vasculares e de outras estruturas, a TC apresentou alto grau de sensibilidade e especificidade, sendo assim um bom exame a ser utilizado nesses casos.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Idoso , Adulto Jovem , Ferimentos Penetrantes/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Lesões do Pescoço/diagnóstico por imagem , Estudos Retrospectivos , Pessoa de Meia-Idade
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