The Amazon suffers from the occurrence of mining along its hydrographic routes, which releases toxic substances into the aquatic environment. The objective of this study was to evaluate the risk of contamination by As and Hg that indigenous peoples are exposed to through the consumption of fish in an area impacted by mining activity in the basin of the Curuá and Baú Rivers, Altamira-PA. In total, 55 fish specimens and 30 surface water samples were collected. The decomposition of the fish samples was done by wet method with the use of nitric acid, hydrogen peroxide, and microwaves. The quantification of total mercury (THg) and total arsenic (TAs) was carried out by inductively coupled plasma optical emission spectrometry with vapor generation (VG-ICP OES). The methodology proposed by the U.S. Environmental Protection Agency was used. The results showed that TAs presents safe levels; however, THg presents a sample with levels up to (4.6 µg g 1), exceeding the permitted levels (1 µg g 1). The risk assessment shows that only the consumption of fish, linked to Hg, represents the existence of deleterious risks to indigenous peoples (hazard quotient (HQ)) > 1). Bioaccumulation factor (BAF) in fish represents a risk to indigenous people, because of the Hg’s presence. The study identified that illegal mining activities are responsible for Hg pollution in the Baú and Curuá Rivers. The fish species analyzed can be used as bioindicators of Hg in the rivers, which is relevant for making environmental and public health policy decisions.

This study provides a risk assessment and risk maps related to the consumption of water contaminated by Al, Ba, Fe and Pb in an industrial area in the Brazilian Amazon. A total of 120 samples of drinking water were collected from 26 locations in the municipality of Barcarena, Pará State. Multiple elements were analyzed by inductively coupled plasma optical emission spectrometry. The quantifiable elements in the samples were Al, Ba, Fe and Pb. Risk assessment was performed according to U.S. Environmental Protection Agency (USEPA) procedures. Results indicate that the highest potential risk of non-carcinogenic adverse health effects for Al was in São João Island; for Ba, Fe and Pb (hazard quotient (HQ) > 1) were in Porto da Balsa community, in the city of Barcarena and Distrito Industrial community, respectively. Maps showed that areas located near Barcarena’s industrial complex are the most affected by water contamination. Therefore, these populations are at higher risk of non-carcinogenic problems, especially children and the elderly, since the majority of the population resides in these areas. Geospatial analysis contributed to delimiting and analyzing risk-change trends in the region, expanding the scope of results to a decision-making process.

The composition of essential oils from flowers of Solanum stipulaceum Roem & Schult collected in May and September was studied for the first time. Effects of g-radiation on volatile constituents were investigated by gas chromatography (GC) with flame ionization detector (FID). In addition, the antileukemic activity was studied by a 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) colorimetric assay against human cell lines HL-60 and THP-1. The main constituents of the essential oil of flowers collected in May were β-caryophyllene (25.8%), γ-gurjunene (11.9%), and β-gurjunene (8.2%), whereas the essential oil of flowers collected in September was mainly composed of β-caryophyllene (26.5%), caryophyllene oxide (11.0%), and γ-gurjunene (10.0%). The main components of essential oil from flowers collected in September were not significantly affected by γ-radiation at lower doses than 10.0 kGy. No cytotoxic activity in leukemic cell lines was observed for non-irradiated samples. However, irradiated samples exhibited slightly cytotoxic activity.

Os processos que promovem alterações em variáveis limnológicas são amplos e necessitam de estudos que considerem as peculiaridades das bacias de contribuição, bem como o uso e cobertura de suas áreas. O presente artigo teve por objetivo comparar a dinâmica de parâmetros limnológicos da Represa Dr. João Penido - Juiz de Fora/MG em diferentes regimes pluviométricos, além de compreender os mecanismos atuantes na variação dos mesmos. O teste t de Student verificou a ocorrência de variação sazonal significativa para os parâmetros: cor, turbidez, ferro, condutividade e demanda bioquímica de oxigênio. Através da Análise Fatorial/Análise de Componentes Principais foi excluída a variável pH por não contribuir para a variância total dos dados além de destacar, dentre as variáveis estudadas, as que mais influenciaram na qualidade da água. Foram utilizadas as quatro primeiras componentes que explicaram 71% da variância total dos dados indicando o escoamento superficial como determinante das variáveis da primeira e da segunda componentes; a contribuição orgânica não associada à precipitação, como sugestiva das variáveis da terceira componente e a dinâmica funcional intrínseca do ambiente aquático como indicativa da quarta componente.

The processes that promote changes in limnological variables are large and require studies that consider the peculiarities of the basins of contribution, as well as the use and coverage of their areas. This article aimed to compare the dynamics of limnological parameters of Dr. Joao Penido reservoir in Juiz de Fora - State of Minas Gerais in different rainfall regimes, as well as understanding the active mechanisms in the variation of the same ones. Student's t-test has revealed the occurrence of significant seasonal variation for the parameters: color, turbidity, iron, electrical conductivity and biochemical oxygen demand. Through factor analysis/principal components analysis variable pH was excluded for not contributing to the variance of all data, highlighting among the studied variables, which contributed more to influence water quality. The first four components were used which explained 71% of the total variance of the data, indicating the runoff as a determinant of the variables of the first and second components; the organic contribution, not associated with the precipitation, as suggestive of the variables of the third component; and intrinsic functional dynamics of the aquatic environment as indicative of the fourth component.

Leaves of Echinodorus macrophyllus (Kunth) Micheli, Alismataceae, were exposed to different doses of γ-radiation (0.00, 1.00, 3.00, 5.00, 10.00, and 20.00 kGy) and the chemical composition of their essential oils was investigated. The extractive process of the essential oil was more favored when the leaves were irradiated. The essential oil components were identified by correlation between GC-FID data and retention parameters obtained from the Kováts method. Moreover, GC-MS analyses of the essential oils were correlated with fragmentation profiles in the NIST standard mass fragmentation data bank. The essential oil of E. macrophyllus contains biologically active constituents of different chemical classes. Acyclic monoterpenes and sesquiterpenes showed increase in concentration when the leaves were exposed to γ-radiation. On the other hand, the component concentrations of some chemical classes were lightly decreased, i.e., for bicyclic monoterpenes, diterpenes, triterpenes, carboxylic esters, and carotenoid derivatives.

From the ethanolic extract of the stem of A. esperanzae ethyl and methyl fatty acid esters, fatty acids, aristolochic I and II acids, and β-cubebin were isolated. In addiction asarinin, populifolic and 2-oxo-populifolic acids, aristolactams AIa and AII, and sitosterol 3-O-β-D-glucopyranoside were also isolated and firstly described in the species. Asarinin and β-cubebin showed antibacterial activity against Bacillus cereus and aristolochic acid I against Staphylococcus aureus and Listeria monocitogenes.