Groundwater were sampled at 17 sampling locations of five districts of Belém City (Pará State, Brazil) in 2011, with objective of evaluate the quality of groundwater sampled in tubular wells potentially used for human consumption. For all groundwater samples were analyzed seven physicochemical parameters and nine trace elements determined by graphite furnace atomic absorption spectrometry (GF AAS). From these results and to better understand the physical and chemical behavior of these waters, multivariate methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to conduct a more thorough evaluation of the original data. The physicochemical parameters studied showed that the groundwater sampled in tubular wells from districts of Marco and Sacramenta had the highest total dissolved solids (140.0 to 244.5 mg L-1), electrical conductivity (198.3 to 340.2 µS cm-1) and turbidity (1.75 to 2.75 UNT) values, indicating the influence of anthropogenic activities contamination in the region, mainly related to the discharge of domestic effluents. In groundwater samples were found 10.4 to 460.5 µg L-1 Fe, 2.0 to 35.2 µg L-1 Cu, < LOD (0.08 µg L-1) to 0.68 µg L-1 Cd, < LOD (0.02 µg L-1) to 5.7 µg L-1 Cr, < LOD (0.01 µg L-1) to 2.3 µg L-1 Ni and < LOD (0.10 µg L-1) to 13.5 µg L-1 Pb. Furthermore, PCA explained 85.8% of the total variance, while the HCA confirmed the correlations found in PCA, allowing evaluating the degree of similarity between samples and identifying the districts most prone to groundwater contamination.
The purpose of this study was to evaluate the levels of Al, Ca, Cu, Fe, Mg, Mn, Na, Pb and Zn in 15 samples of five fish species (Brachyplatystoma rousseauxii, Brachyplatystoma filamentosum, Cynoscion leiarchus, Brachyplatystoma vaillanti e Colossoma macropomum) obtained in municipal market of Belém (Pará State, Brazil). These samples were digested in a cavity microwave oven using a 3.5 mol L-1 nitric acid solution and concentrated hydrogen peroxide. Total concentrations of the studied elements were determined by flame atomic absorption spectrometry (FAAS) and graphite furnace atomic absorption spectrometry (GF AAS). The contents of the elements in fish samples ranged from 90.
No presente estudo objetivou-se elaborar produtos artesanais (doce em massa e geleia) e avaliar as características físico-químicas e sensoriais dos produtos saborizados com flor de camomila e canela em pau produzidos a partir dos frutos de abacaxi Pérola. Foi realizada caracterização física de 100 amostras de frutos através das medidas de peso dos frutos (PF), peso da polpa (PP), peso da casca (PC), peso da coroa (PCA), avaliação do diâmetro, comprimento dos frutos e rendimento da polpa. Para a caracterização físico-química da polpa, do albedo e dos produtos artesanais elaborados foram realizadas as análises de pH, acidez total titulável, sólidos solúveis totais, umidade, cinzas, teor de proteínas totais, lipídios, carboidratos e o valor energético total. Os resultados obtidos das análises físico-químicas e sensoriais foram realizados pelo teste de Tukey a 5% de probabilidade. Em relação à caracterização física dos frutos de abacaxi Pérola, os parâmetros avaliados como comprimento (31,05 cm), diâmetro (14,86 cm) caracterizam os frutos no formato cônico. Quanto aos valores obtidos para o peso médio dos frutos (1.350,50 kg), e rendimento da polpa (53,33%) estão acima dos valores relatados na literatura. Os teores médios de pH, °Brix, umidade, cinzas, carboidratos e valor energético total para a polpa de abacaxi estão próximos aos estipulados pela Tabela Brasileira de Composição de Alimentos – TACO e ANVISA. De acordo com os resultados obtidos, os produtos podem se tornar uma opção de aproveitamento integral dos frutos de abacaxi, logo uma forma alternativa de renda para o pequeno produtor da região do Sudeste do Pará.
This study aimed to evaluate the mineral composition in native and non-native Amazonian fruits using flame atomic absorption spectrometry (FAAS) and multivariate methods, such as principal component analysis (PCA) and hierarchical cluster analysis (HCA), in order to conduct a more thorough evaluation of the original data. The accuracy was checked by certified reference material analysis (Poplar leaves) and spike experiments. The results of the analysis were in agreement with the certified values, with analytical recoveries for all analytes in an acceptable range from 82 to 113%, and relative standard deviations (RSD) were in the range of 0.2-18%. Furthermore, PCA explained 68% of the total variance, while HCA confirmed the correlations found in the PCA, allowing for the evaluation of the degree of similarity between the fruits studied. These results will be used to better understand the distribution of inorganic constituents within these Amazonian fruits.
Amostras de águas subterrâneas foram coletadas em 20 locais de amostragem distribuídos em nove bairros da Cidade de Parauapebas (Estado do Pará, Brasil), em 2019, com o objetivo de avaliar a qualidade das águas subterrâneas captadas em poços tubulares potencialmente utilizados para consumo humano. Para todas as amostras de águas subterrâneas foram analisados nove parâmetros físico-químicos, tais como temperatura (T), potencial hidrogeniônico (pH), condutividade elétrica (CE), turbidez (TRB), cor , teor de cloreto (Cl-) e sólidos totais dissolvidos (STD), com a intenção de contribuir para o controle da qualidade de potabilidade das águas subterrâneas de acordo com os limites estabelecidos pelo Ministério da Saúde (Portaria Nº 2914/2011) e Conselho Nacional de Meio Ambiente (Resolução Nº 396/2008). Os parâmetros físico-químicos estudados mostraram que nas águas subterrâneas coletadas em poços tubulares no bairro Da Paz e foram encontrados os valores mais altos de sólidos totais dissolvidos (175,0 a 271,8 mg L-1), condutividade elétrica (136,3 a 216,7 µS cm-1) e cor (5,0 a 15,0 uH), servindo de indicativos para identificação de possíveis atividades antropogênicas de contaminação na região, principalmente em relação à descarga de efluentes domésticos. Os resultados obtidos dos parâmetros físico-químicos para todas as amostras se apresentaram abaixo dos limites estabelecidos de potabilidade para águas subterrâneas de acordo com a legislação Brasileira.
Groundwater contamination by polycyclic aromatic hydrocarbons (PAH) may pose a risk to human health, as these compounds are considered to be highly toxic, carcinogenic and/or mutagenic and bioaccumulative. The aim of this study was to evaluate and determine PAH levels in groundwater samples collected from tubular wells in a city of northern Brazil by gas chromatography with flame ionization detector (GC-FID) used by the population for consumption. Sample pre-treatment using solid-phase extraction cartridges was performed in order to promote an enrichment of the PAH fraction of interest and to remove interferences from the matrix to further determine PAH in samples by GC-FID. The results obtained showed that all groundwater samples studied presented PAH levels lower than maximum values allowed by MS 2914/2011 and CONAMA 396/2008. The developed procedure is characterized by low limits of detection and quantification, equal to 0.024-0.113 µg L −1 and 0.079-0.378 μg L −1 , respectively, good linearity (r 2 > 0.99). The recoveries obtained for 16 PAH by the addition and recovery method ranged from 85.4 to 105.7% with good precision (RSD < 5.0%). The results of this study showed that the method developed is fast, accurate and robust with high efficiency for identification and determination of 16 PAH in groundwater samples.
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