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Studies have shown that shell morphology and enzymatic activities in mollusks are affected by contaminants exposure. However, the correlation between enzymatic activities and the biomineralization process are not fully understood. The present study used a transplant bioassay and field sampling to evaluate shell measurements and the activities of carbonic anhydrase, Ca2+-ATPase, and Mg2+-ATPase in Lottia subrugosa sampled in Brazilian sites under different contamination levels. Results showed that, in general, shells from the reference site (Palmas) were more rounded than the ones from the contaminated site (Balsa). Effects in enzymatic activities in specimens from transplant bioassay were attributed to the known high contaminant levels present at Balsa. While the lack of enzymatic activity alterations during field sampling was attributed to physiological adaptation to contaminants exposure. Enzymatic activities were not correlated to shell biometric parameters in field sampling, indicating that these enzymes were not related to shell alterations detected in the present study.

Many cities worldwide are established adjacent to estuaries and their catchments resulting in estuarine contamination due to intense anthropogenic activities. The aim of this study was to evaluate if fish living in an estuarine urban waterway were affected by contamination, via the measurement of a suite of biomarkers of fish health. Black bream (Acanthopagrus butcheri) were sampled in a small urban embayment and a suite of biomarkers of fish health measured. These were condition factor (CF), liver somatic index (LSI), gonadosomatic index (GSI), hepatic EROD activity, polycyclic aromatic hydrocarbon (PAH) biliary metabolites, serum sorbitol dehydrogenase (s-SDH) and branchial enzymes cytochrome C oxidase (CCO), and lactate dehydrogenase (LDH) activities. The biomarkers of exposure EROD activity, and pyrene- and B(a)P-type biliary metabolites confirmed current or recent exposure of the fish and that fish were metabolizing contaminants. Relative to a reference site, LSI was higher in fish collected in the urban inlet as was the metabolic enzyme LDH activity. CF, GSI, s-SDH, CCO, and naphthalene-type metabolites were at similar levels in the urban inlet relative to the reference site. PAH biliary metabolite ratios of high-molecular-weight to low-molecular-weight suggest that fish from the urban inlet were exposed to pyrogenic PAHs, likely from legacy contamination and road runoff entering the embayment. Similarly, the sediment PAH ratios and the freshness indices suggested legacy contamination of a pyrogenic source, likely originating from the adjacent historic gasworks site and a degree of contamination of petrogenic nature entering the inlet via storm water discharge. Biomarkers of exposure and effect confirmed that black bream collected in the Claisebrook Cove inlet, Western Australia, are currently exposed to contamination and are experiencing metabolic perturbations not observed in fish collected at a nearby reference site.

Made available in DSpace on 2018-12-11T17:07:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-02-01 Financiadora de Estudos e Projetos Here we explore the dose-dependent response of the tropical fish tambaqui (Colossoma macropomum) to intraperitoneal injection of benzo[a]pyrene (BaP) at doses of 0 (carrier control), 1, 10, 100 and 1000 μmolar BaP Kg−1 Hepatic ethoxyresorufin-O-deethylase (EROD) activity showed a bell-shaped dose-dependent response curve, where the highest injected BaP dose caused enzyme inactivation. Activities of hepatic catalase (CAT) and superoxide dismutase (SOD) increased at the highest dose relative to the carrier control group. Lipid peroxidation (LPO), serum-sorbitol dehydrogenase (s-SDH) and DNA damage in blood cells were higher for all BaP doses when compared to the carrier control group. At high dosage, the production of BaP metabolites was paralleled by induced activity of the antioxidant enzyme SOD, and high levels of DNA damage in blood cells. In a similar way, high LPO was concomitant to elevated s-SDH in the bloodstream, suggesting that lipid peroxidation caused the loss of membrane integrity and leakage of s-SDH from hepatocytes into the bloodstream. These biomarkers were also positively co-correlated. The results demonstrate the potential use of a suite of biomarkers for tambaqui living in contaminated tropical aquatic environments. In particular, we recommend the analysis of DNA damage in blood cells, as this was highly correlated with all other biomarkers. Brazilian National Institute for Research in the Amazon Laboratory of Ecophysiology and Molecular Evolution, Ave André Araújo 2936 Biosciences Institute São Paulo State University − UNESP Coastal Campus, Pça Infante Dom Henrique s/n°, P.O. Box 73601, São Vicente Department of Environment and Agriculture Curtin University, P.O. Box U1987 Biosciences Institute São Paulo State University − UNESP Coastal Campus, Pça Infante Dom Henrique s/n°, P.O. Box 73601, São Vicente

The present work aimed to investigate the effects of acute (12, 24, 48 and 96 h) and subchronic (168 and 336 h) exposure of seahorse, Hippocampus reidi to water-accommodated fraction (WAF) of diesel fuel on biotransformation parameters, antioxidant defenses and DNA integrity. In addition, a recovery experiment was performed, where the organisms remained in absence of the contaminant for 336 h, after WAF exposure for 168 h (totaling 504 h). At the end of each experimental protocol, the concentration of pyrene-, benzo(a)pyrene- and naphthalene-type metabolites in bile, hepatic activity of glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT), as well as lipid peroxidation (LPO) levels in hepatocytes, were analyzed, in addition to the DNA damage and the micronucleus (MN) test in the peripheral blood. It was observed that both acute and subchronic WAF exposure affected the investigated parameters in different ways. In general, the exposed groups presented higher mean values for the investigated parameters if compared with their respective controls. After the recovery experiment, the mean values of PAH metabolites, LPO, DNA damage and MN frequency were significantly lower than those of animals exposed for 168 h, indicating that the recovery period was appropriately long for the evaluated biomarkers return to the control levels. The results indicated that the selected H. reidi biomarkers proved to be adequate and complementary tools in determining the first impacts of acute and subchronic exposure caused by WAF of diesel fuel in fish, as well as their recovery in clean water.

Hoplosternum littorale is an Amazon fish that lives in urban areas surrounded by polluted igarapes, where elevated copper concentrations eventually occur. The central goal of this study was to evaluate the associated effects of high temperature and copper contamination on survival time and biochemical responses of the Amazonian fish species H. littorale. We exposed fish to two nominal dissolved copper concentrations (50 and 500 µg l−1) and combined temperatures of 28 and 34°C. Our findings showed that the combination of these variables affects the survival time of this species. The activity of the biotransformation enzymes ethoxyresorufin-O-deethylase and glutathione-S-transferase showed no alterations in fish within all treatments. The increase of reactive oxygen species and the decrease in potential total antioxidant capacity promoted the imbalance in the antioxidant system. An induction in superoxide dismutase activity occurred in fish exposed to copper concentrations of 50 and 500 µg l−1 at both temperatures, suggesting liver impairments. Thus, we suggest that H. littorale is sensitive to copper, and this sensitivity is increased further with exposure to high temperatures, particularly in the survival time and reactive oxygen species formation of this fish species.

Given the reported degraded nature of DOC in the Rio Negro, and low oxygen, pH, and bacterial riverine levels, we hypothesized: (1) DOC would have strong humic and fulvic acid fluorescence signals with high aromaticity and large mean molecular weight; and (2) photo-oxidation rates would be slow, and reactive oxygen species (ROS) concentrations low, producing no oxidative stress in biota. We surveyed the environment and properties of DOC and explored DOC photo-oxidation and fish sensitivity to DOC products. DOC properties were investigated using absorption and fluorescence indices and parallel factor analysis (PARAFAC) of excitation–emission matrices. ROS concentrations were measured spectrophotometrically. A native fish, Hemigrammus levis, was exposed to photo-oxidizing DOC and its tissues (brain, gill, liver) assayed for changes in antioxidant and biotransformation enzymes. With respect to our hypotheses, (1) DOC was highly terrigenous, with high SAC340 values (aromaticity), high capacity to produce ROS, and high tryptophan-like fluorescence (bacterial, autochthonous signal); (2) photo-oxidation rates were appreciable, while products were related to mean UV-radiation levels (total radiation was constant). ROS levels were often higher than freshwater averages, yet fish experienced no oxidative stress. Results suggest photo-oxidation influences patterns in C-cycling, bacterial production and community dynamics between wet and dry seasons.

The contamination of waterbodies is a worldwide concern due to the increasing urbanization and industrialization of the cities without good effluent management. Touristic cities can suffer with the number of people during high seasons periods, which can lead to an elevated use of natural resources and effluents discharges. Moreover, raining seasons, either high or low, can also play an important role in contaminating waterbodies once a dilution or concentration of contaminants may take place. The present study evaluated the water quality of the Tejereba River (Guarujá, Brazil) during the high season (January) and low season (March and May) in 2018. Reduction in water quality was observed in May, a month with low pluviosity and low tourism. The integrated data analysis (PCA) showed a positive correlation between the physicochemical parameters and the month of May, in which they were negatively correlated with pluviosity and the percentage of tourists. Despite the deterioration of water quality in May, no toxicity to Daphnia magna was observed. Our work showed that water quality (physicochemical and microbiological parameters), during the studied months, is more related to raining seasons than to the presence of tourists in Guarujá, Brazil. La contaminación de los cuerpos del agua es una preocupación mundial debido a la creciente urbanización y industrialización de las ciudades sin una buena gestión de los efluentes. Las ciudades turísticas pueden sufrir por la cantidad de personas mientras los períodos de temporada alta, lo que puede conducir a un alto uso de los recursos naturales y descarga de efluentes. Además, las temporadas de lluvias, sean altas o bajas, también pueden jugar un papel importante en la contaminación de los cuerpos del agua, ya que pueden producirse diluciones o concentraciones de contaminantes. El presente trabajo evaluó la calidad del agua del río Tejereba (Guarujá, Brasil) durante la temporada alta (enero) y temporada baja (marzo y mayo) en 2018. La reducción de la calidad del agua se observó en mayo, un mes de escasas precipitaciones y escaso turismo. El análisis integrado de datos (PCA) mostró una correlación positiva entre los parámetros físico-químicos y el mes de mayo, en el que se correlacionaron negativamente con las precipitaciones y el porcentaje de turistas. A pesar del deterioro de la calidad del agua en mayo, no se observó toxicidad para Daphnia magna. Nuestro trabajo mostró que la calidad del agua (parámetros físico-químicos y microbiológicos) en los meses evaluados está más relacionada con las temporadas de lluvias que con la presencia de turistas en la ciudad de Guarujá, Brasil. A contaminação de corpos d'água é uma preocupação mundial devido à crescente urbanização e industrialização das cidades sem um bom gerenciamento de efluentes. As cidades turísticas podem sofrer com o número de pessoas durante os períodos de alta temporada, o que pode levar a um elevado uso de recursos naturais e lançamento de efluentes. Além disso, as estações chuvosas, sejam altas ou baixas, também podem desempenhar um papel importante na contaminação de corpos d'água, uma vez que pode ocorrer diluição ou concentração de contaminantes. O presente trabalho avaliou a qualidade da água do rio Tejereba (Guarujá, Brasil) durante os períodos turísticos de alta (janeiro) e baixa temporada, (março e maio) no ano de 2018. A redução da qualidade da água foi observada em maio, mês de baixa pluviosidade e baixo turismo. A análise integrada de dados (PCA) mostrou correlação positiva entre os parâmetros físico-químicos e o mês de maio, na qual se correlacionaram negativamente com a pluviosidade e o percentual de turistas. Apesar da deterioração da qualidade da água em maio, nenhuma toxicidade para Daphnia magna foi observada. Nosso trabalho mostrou que a qualidade da água (parâmetros físico-químicos e microbiológicos), nos meses estudados, está mais relacionada às estações chuvosas do que à presença de turistas na cidade de Guarujá, Brasil.

Os impactos da visitação compreendem toda ação humana direta que provoque dano ao meio natural, relacionada ao comportamento inadequado do visitante ou aos problemas de planejamento para a demanda de uso. Portanto, o objetivo foi avaliar os possíveis impactos causados pela visitação de duas trilhas principais (Costão e Deserta), localizadas na Reserva de Desenvolvimento Sustentável da Barra do Una, durante o verão (alta visitação) e no outono (baixa visitação) de 2017. Para isso, as trilhas Costão e Deserta foram seccionadas, sendo respectivamente estabelecidos 4 e 10 pontos, onde foram avaliados indicadores de impactos físicos, biológicos e sociais por meio do método Visitor Impact Management. Os achados demonstraram, em ambas as trilhas, uma redução nos impactos relacionados aos problemas de drenagem, ao serem comparadas as estações do verão com o outono. A presença de lixo na trilha da Deserta na estação do outono foi menor quando comparada ao verão, enquanto os danos aos recursos naturais na trilha do Costão foram maiores no outono que no verão. Embora as trilhas estudadas estejam localizadas em uma Unidade de Conservação, a ausência de controle de visitação pública, assim como a falta de infraestrutura colaboram de forma negativa, resultando em danos de diferentes gravidades. Por fim, as ações propostas no presente estudo, como trilha guiada com monitor ambiental, controle de visitação pública, instalação de corrimãos, degraus e placas podem ser benéficas para reduzir e/ou reverter os impactos encontrados em ambas as trilhas.

The present study aimed to evaluate the biometric and hematological indices in Mugil curema collected in two Neotropical estuaries in the south coast of Brazil, and to investigate if such variables can be influenced by seasonality and degree of anthropogenic influence. Differences between seasons and estuarine systems were observed, where the dissolved oxygen and salinity, together with the historical contamination of the Santos estuarine system (SES), seem to play an important role in the biological response. Fish from the SES presented, in general, high responses of the hematological variables (red and white series) and the hepatosomatic index, relative to those fish from Peruibe estuarine system (PES), even with the remote contamination present at PES, while no erythrocytic abnormalities or micronucleus were observed in fish collected at SES and PES in both seasons. The present work demonstrated that M. curema collected at SES are experiencing hematological and metabolic perturbations that are not observed in fish collected at PES.