The increasing use of agrochemicals negatively affects the environment while the generated residues impact the hydrographic networks which feed the rivers and fishing ponds, so this work investigates pesticide contamination in the supply and fishing tank waters and bottom sediment of fee-fishing ponds located in micro-basins planted with sugarcane. The results are expected to indicate the water contamination level and the impact on both the environment and human health. Therefore, water and bottom sediments from fishing ponds nearby sugarcane plantations were sampled quarterly over a year. The pesticide residues in the samples were determined by high-performance liquid chromatography coupled to mass spectrometry. The contaminants detected in the ponds were tebuthiuron (2.908 ng mL −1), metolachlor (1.211 ng mL −1), hexazinone (1.065 ng mL −1), atrazine (1.008 ng mL −1), ametryn (1.004 ng mL −1), and clomazone (0.858 ng mL −1) in the water samples while metolachlor (2.308 ng g −1), tebuthiuron (0.540 ng g −1), hexazinone (0.394 ng g −1), and isoxaflutole (0.004 ng g −1) were detected in the sediment samples. Additionally, the results show that the size of sugarcane cultivated area nearby the fishing ponds, herbicide physicochemical parameters, and applications coinciding with high rainfall are all relevant factors for water contamination. Furthermore, sediment contamination is directly correlated with the herbicides in the water ponds.

RESUMO Com intenso consumo e lançamento contínuo em efluentes domésticos e industriais, a cafeína tem sido regularmente detectada em meios aquáticos por todo o mundo. Esse psicoativo é considerado um excelente indicador de contaminação na água, relacionada à atividade humana. No entanto, os impactos que pode ocasionar à saúde e ao ambiente ainda não são bem compreendidos. Dessa forma, o objetivo deste trabalho foi verificar a presença da cafeína em água bruta e tratada por uma estação de tratamento de água convencional, em diferentes períodos hidrológicos, e avaliar o risco potencial que ela representa ao ambiente aquático. A cafeína foi detectada em todas as amostras de água bruta. A maior concentração foi observada no período mais intenso de seca. Ela não foi detectada na água tratada. O composto é considerado como de alto risco ao ambiente aquático. Os resultados indicam a vulnerabilidade do manancial em questão.

The world wide use of tilapia for different approaches in fish bioassay was exploited to assess the accumulation of copper and cadmium, in isolated forms and in combination in gills and muscular tissue in the specie Oreochromis niloticus, which is of economical relevance in fish consumption in the Sao Paulo State, Brazil. To reach for these goals, semi-static chronic toxicity tests were carried out during 21 days by using two dissolved concentrations of each trace element as follow: LC50/10 and the average of LC50/10 and LC50/100. Fish samplings to assess for the kinetic trace element absorptions with time were performed at 24, 96 hours, 7, 14 and 21 days. After 14 days of exposure gills had higher concentrations for both elements (5.20 mg Kg-1 Cu and 4.89 mg kg-1 Cd), than the muscular tissue (0.79 mg Kg-1 Cu e 0.32 mg Kg-1 Cd). A competition for absorption was established when both elements were in combination, being the maximum absorbed concentrations, 1.81 mg Kg-1 Cu and 1.54 mg Kg-1 Cd for the gills and 0.63 mg Kg-1 Cu and 0.12 mg Kg-1 Cd for the muscular tissue. The Tukey test used for the statistical evaluation of the exposure period times dissolved metal concentration interactions revealed the interference of the basal Cd and Cu contents of the fish on the results. Despite the verified bioaccumulation, in which BCF for Cd were lower than the BCF for Cu, the fractions of the LCs50 were not lethal to the fish. Tilapia did not concentrate Cu and Cd in the edible tissue at concentrations to bring restrictions for human consumption.

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