The influence of beach geology and morphodynamics on chemical pollution assessments following a mining accident.

In the present study the distribution of chemical elements in beaches adjacent to the Doce River mouth hit by the tailings mud from a mining accident were assessed. Sedimentological and morphological coastal aspects were also considered. The results indicate that wave-exposed delta plain beaches exhibit high resiliency, despite their proximity to potential pollution sources. On the other hand, shore platform beaches tend to accumulate chemical elements, mainly due to limited cross-shore sediment exchanges. Arsenic concentrations in the evaluated shore platform beaches were significantly higher than the delta plain beach. Shore platform beaches are more susceptible to frequent flooding and to higher elemental concentrations at the berm and beach face. Thus, the morphological characteristics of the assessed shore platform beaches, and input from the mud plume must be considered in a joint assessment strategy in order to obtain a broad understanding of the actual scenario regarding beach contamination.

Changes in the renal function after acute mercuric chloride exposure in the rat are associated with renal vascular endothelial dysfunction and proximal tubule NHE3 inhibition.

Mercury is an environmental pollutant and a threat to human health. Mercuric chloride (HgCl2)-induced acute renal failure has been described by several reports, but the mechanisms of renal dysfunction remain elusive. This study tested the hypothesis that HgCl2 directly impairs renal vascular reactivity. Additionally, due to the mercury toxicity on the proximal tubule, we investigated whether the HgCl2-induced natriuresis is accompanied by inhibition of Na+/H+ exchanger isoform-3 (NHE3). We found that 90-min HgCl2 infusion (6.5 µg/kg i.v.) remarkably increased urinary output, reduced GFR and renal blood flow, and increased vascular resistance in rats. "In vitro" experiments of HgCl2 infusion in isolated renal vascular bed demonstrated an elevation of perfusion pressure in a concentration- and time-dependent manner, associated with changes on the endothelium-dependent vasodilatation and the flow-pressure relationship. Moreover, by employing "in vivo" stationary microperfusion of the proximal tubule, we found that HgCl2 inhibits NHE3 activity and increases the phosphorylation of NHE3 at serine 552 in the renal cortex, in line with the HgCl2-induced diuresis. Changes in renal proximal tubular function induced by HgCl2 were parallel to increased urinary markers of proximal tubular injury. Besides, atomic spectrometry showed that mercury accumulated in the renal cortex. We conclude that acute HgCl2 exposure causes renal vasoconstriction that is associated with reduced endothelial vasodilator agonist- and flow-mediated responses and inhibition of NHE3-mediated sodium reabsorption. Thus, our data suggest that HgCl2-induced acute renal failure may be attributable at least in part by its direct effects on renal hemodynamics and NHE3 activity.

Water assessment of the Itapemirim River/Espírito Santo (Brazil): abiotic and toxicogenetic aspects.

The Itapemirim River is considered one of the most important water resources in the state of Espírito Santo, Brazil. However, environmental problems due to continuous anthropogenic contamination are threatening its potential use. This study assessed water quality by analyzing abiotic and toxicogenetic aspects of the water from four stations along the river. Samples were collected in both dry and rainy seasons. Most of the abiotic variables were below the threshold established by CONAMA Resolution No. 357/2005, and so were most of the metals. However, Al and Cu contents were above those allowed by legislation, ranging from 0.2 to 0.9 mg/L. Regarding toxicogenetic aspects, genotoxic effects were observed in meristematic cells of Allium cepa, in micronucleus test and comet assay of Oreochromis niloticus, and CHO-K1 cells. Mutagenic effects were significant at RI 02 (0.34), RI 03 (0.46), and RI 04 (0.12) stations on the first campaign in A. cepa F1 cells, compared to the negative control (0.0). The second campaign revealed the same results, but with the addition of samples from RI 01 (0.17) and RI 03 (0.18) showing mutagenicity in the micronucleus test with fish erythrocytes when compared to the negative control (0.3). Essentially, all the samples evaluated in both campaigns showed damage in A. cepa, O. niloticus, and CHO-K1 cells, thus demonstrating that the water quality of the Itapemirim River is compromised and requires action plans for its recovery.

Accumulation of trace metals in eggs and hatchlings of Chelonia mydas.

BACKGROUND: The objective of this study was to verify the accumulation of trace metals in eggs and hatchlings of Chelonia mydas, evaluating if metal accumulation is originated from maternal transfer and/or from the incubation environment. Other assessments were also performed, as metal distribution in different tissues (blood, kidney, liver, muscle, and turtle shells) of newly hatched turtles, and genotoxic analysis, to verify possible damages caused by the presence of metals. METHODS: The assessments were carried out by quantifying Cd, Ni, Pb, Mn and Fe in egg sample collected during laying time (eggshells (ELT) and egg content (EC)), eggshells from newly hatched turtles (ENH), hatchlings tissues (H - blood, kidney, liver, muscle, and shell)) (n = 18 for each biological sample - 3 of each nest) and nest sediments (n = 6, one of each nest). Comparative analysis were made between ELT and ENH, as well as between egg content (EC) and the sum of tissue samples from hatchlings, using Mann-Whitney hypothesis test (p < 0,05). The amount of metals in different hatchling was quantified and followed by the Dunn post-test. A principal component analysis (PCA) was also employed. RESULTS: Metals studied were found in all investigated samples. The concentration of a great amount of investigated metals was significantly higher (P=<0.001) in eggshells from ENH than in ELT. An increase in Cd (2.16-fold), Pb (3.47-fold), Fe (6.83-fold) and Mn (195.57-fold) concentration was noticed in ENH. We also observed an increase in Fe (1.59-fold), Mn (1.74-fold) and Ni (1.59-fold) concentration in hatchling, when compared with EC, due to transfer from nest sediments. In relation to the hatchling's tissues, blood was shown to accumulate higher concentrations of Ni and Pb, while shells accumulated more Cd and Fe, and Mn is more associated with liver and kidney. Fe was the highest accumulated metal in both tissues, and muscles presented discrete concentrations of Ni, Mn, and Pb. A mean concentration of 1.25‰ MN was obtained in C. mydas hatchlings, indicating that the accumulation of metals in hatchlings didn't cause toxicology effects. CONCLUSION: Hatchlings accumulate metals through the maternal and sediment transfer, although the levels of metal accumulation were not enough to cause genotoxic damage.

Metals, arsenic, pesticides, and microcystins in tilapia (Oreochromis niloticus) from aquaculture parks in Brazil.

The production of Nile tilapia (Oreochromis niloticus) in Brazil exhibits the highest growth rate in the world and represents approximately 45% of the total fish production. The objective of the present study was to assess the risk for human health due the consumption of tilapia farmed in net cages in eight aquaculture parks in Brazil. The concentrations of pesticides (40 compounds), metals (Mn, Ni, Zn, Cd, Pb, and Sn), arsenic, and cyanotoxins (microcystins) were evaluated in 16 fish from each park. Among analyzed pesticides, pyraclostrobin (0.18-0.32 mg/kg) and fenthion (0.0026-0.0037 mg/kg) exhibited values above the limit of quantification in the tilapia from Aracoiaba, Castanhão, and Ilha Solteira. The highest concentrations of As (0.44 µg/g) in fish tissues were found in Juara, Mn (0.21 µg/g) in Castanhão, and Zi (11.5 µg/g) were found in Três Marias. Furnas and Linhares exhibited the lowest metal concentrations. The estimated daily intake of muscle by the average Brazilian with 70 kg body weight is below the reference dose for all studied metals in all parks. Total free microcystins showed an accumulation pattern (muscle < gill < liver). The highest concentration in muscle was found in Castanhão (1043 µg/kg) samples. The results showed that fish exhibited metal, As, and pesticide tolerable daily intake (TDI) below the limit and pose low risk for human consumption. Otherwise, TDI for microcystins in fish of all studied parks was above the maximum level recommended by the World Health Organization, indicating that there exists a toxicity risk of fish consumption.

Composition analysis of the cathode active material of spent Li-ion batteries leached in citric acid solution: A study to monitor and assist recycling processes.

Spent Li-ion batteries (LIBs) despite being produced with valuable metals from non-renewable natural resources are considered hazardous solid wastes because they contain metals and organic solvents pollutants for the environment. Due to this, it becomes necessary to know the chemical composition of these spent batteries to assist in the proper disposal and/or recycling process. This study aimed to provide quantitative data regarding the chemical composition of the cathode active material (CAM) of eight different spent LIBs used in cell phones and propose relationship with their energy capacity, year of manufacture and brand. CAM powder was leached using an environmentally friendly process with citric acid (2.0 mol L-1) and H2O2 (0.25 mol L-1), and the metals concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP OES). Co (43-67 wt%), Li (5.3-6.8 wt%), Mn (0.8-8.2 wt%), Ni (0.1-11.7 wt%) and Al (0.06-3.2 wt%) were present in higher concentrations, whereas Cr (0.0005-0.002 wt%), Cu (0.01-0.05 wt%), Mg (0.005-0.02 wt%), Ti (0.001-0.07 wt%), Ga (0.0009-0.03 wt%) and Zn (0.009-0.05 wt%) were present in lower concentrations. The result obtained showed a considerable variation between CAM elemental composition, which may be related to type of electrolyte, energy capacity and year of manufacture. Since this difference in chemical composition is not shown on product labels, this work using a green leaching process and a suitable analytical method may assist in the recycling processes and avoid the inappropriate disposal of the material.

Trace elements influence the hatching success and emergence of Caretta caretta and Chelonia mydas.

Trace elements from industrial, domestic and agricultural activities can be transferred into marine environments, affecting the survival of sea species. Due to their global distribution, sea turtles are recognized as indicators of ocean pollution. The aim of this work was to quantify Ba, Cd, Cr, Cu, Fe, Mn, Pb, Sr and Zn using inductively coupled plasma optical emission spectrometry (ICP-OES) in the eggs and offspring of Caretta caretta and Chelonia mydas from two important nesting beaches, Guanabara Beach, Anchieta, and Trindade/Martim Vaz Island, Espírito Santo, Brazil. C. mydas pups and eggs collected on Trindade/Martim Vaz Island presented significant differences in Ba, Cr, Cu, Mn and Sr (p < 0.001). Higher concentrations of Ba, Pb, and Sr were detected in eggs of this species in comparison to those of C. caretta on Guanabara Beach, Anchieta. Ba and Cd presented higher concentrations in pups than in eggs of C. caretta, which could indicate nesting pollution. Positive correlations between trace element concentrations and hatching success in C. caretta nests from Guanabara Beach, Anchieta, could be identified for Cu and Zn (r²â€¯= 0.86, F2.7 = 21, p < 0.001). Emergence success was influenced by Cu and Cd (r²â€¯= 0.84, F2.7 = 18.9, p = 0.002). In addition, Ba and Cd also influenced the emergence sucess (r²â€¯= 0.56, F2, 10 = 6.29, p = 0.017). The hatching success of C. mydas was influenced by the concentration of Cu (r²â€¯= 0.53, F2.14 = 7.82, p = 0.005). Further studies including the analyzed areas and migratory routes should be performed to promote conservation management at these beaches.

Chronic iron overload induces vascular dysfunction in resistance pulmonary arteries associated with right ventricular remodeling in rats.

Although iron excess is toxic to the vasculature and even that pulmonary hypertension has been reported in this scenario, the role of iron overload per se remains to be clarified. This study aimed to test the effects of chronic iron-overload in rats on the morphophysiology of resistance pulmonary arteries (RPA) and right ventricle (RV) remodeling. Rats were injected with saline or iron-dextran (10, 100 and 200 mg/kg/day i.p.) for 28 days. Our results indicated increased circulating iron with significant lung deposits. Moreover, rats treated with the highest dose exhibited RV dysfunction and hypertrophy; inward remodeling and increased vasoconstriction of the RPA. Vascular hyperreactivity was accompanied by reduced nitric oxide (NO), and was reversed by incubation with Dimethylsulfoxide, Catalase and Tempol. The NADPH oxidase subunit gp91phox was increased due to iron-overload, and incubation with angiotensin II type-1 receptor (AT1) antagonist losartan not only reduced oxidative stress but also restored vascular function. Thus, we concluded that AT1 pathway plays a role in pulmonary vascular dysfunction by increasing oxidative stress and reducing NO bioavailability, thereby contributing to vascular remodeling and pulmonary hypertension of iron-overload. This finding should instigate future studies on the beneficial impacts of in vivo blockade of AT1 receptor under iron overload.

Concentração de elementos traços em serpentes do litoral e da região serrana do Espírito Santo / Trace element concentration in snakes of coastal and serrana region of the State of Espírito Santo, Brazil

Os elementos químicos, em sua maioria, encontram-se em ciclos bioquímicos e geoquímicos fechados e em concentrações que não causam efeitos nocivos aos organismos. Contudo, ações antrópicas aceleradas promovem alterações ambientais, como o aumento no aporte de contaminantes. Com essas informações, o presente trabalho buscou caracterizar a presença aos elementos traços em duas espécies de serpentes comuns na região sudeste, Boa constrictor e Bothrops jararaca. Os exemplares de B. constrictor (n=18) foram provenientes de atropelamentos ocorridos no trecho da Rodovia ES-060 do Km 0 ao Km 67,5. Os exemplares de B. jararaca (n=18) foram capturados por fazendeiros na zona rural da região serrana do Espírito Santo. Foram analisados 1 grama de fragmento de rim, de espécimes necropsiados. Os rins coletados foram digeridos com mistura ácida (HNO3;HCl; 1:1) a 300oC, 40min e a quantificação de microelementos (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn) foi realizada por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Não foram observadas diferenças significativas entre machos e fêmeas, exceto para Cromo nas B. constrictor (p=0,03), com média de 1,6595 nas concentrações de Cr nas fêmeas e 0,2896 em machos. Contudo, quando foram comparadas as diferentes espécies de serpentes, diferentes concentrações foram encontradas, para todos os elementos determinados, com destaque para o Ferro com uma concentração de 106,2mg/g em B. constrictor e 120,3mg/g em B. jararaca, provavelmente por esses animais virem de áreas próximas à portos de minério de ferro. A concentração de Zinco em B. constrictor foi de 1261,8mg/g e em B. jararaca foi de 28,4mg/g. O presente estudo indica que as serpentes analisadas, que habitam as regiões da Grande Vitória e serrana do Espírito Santo apresentam elevadas concentrações dos microelementos Zn e Fe.(AU)

Chemical elements are mostly involved in biochemical and geochemical cycles in concentrations which are harmless for organisms. However, accelerated human actions promote environmental changes such as the increase in contaminant intake. With this information, this study aimed to characterize the presence of trace elements in two snake species common in Southeastern Brazil, Boa constrictor and Bothrops jararaca. Copies of B. constrictor (n=18) were from pedestrian accidents which occurred on Highway stretch ES-060 from Km 0 to Km 67.5. Copies of B. jararaca (n=18) were captured by farmers in a rural mountainous area of Espíirito Santo State, Brazilo. They were analyzed 1 kidney fragment grass, autopsied specimens. Harvested kidneys were digested with acid mixture (HNO3 e HCl 1:1) at 300°C, 40 min and quantification of microelementos (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were determined by spectrometric optical emission with inductively coupled plasma (ICP OES). significant differences between males and females were observed, except for Chrome in B. constrictor (p=0.03), with an average of 1.6595 in Cr concentration of females and 0.2896 in males. However, when different species of snakes were compared, different concentrations were found for all elements, especially iron with a concentration of 106.2mg/g in B. constrictor and 120.3mg/g in B. jararaca; probably these animals came from areas near iron ore ports. The concentration of zinc in B. constrictor was 1261.8mg/g and in B. jararaca 28,4mg/g. This study indicates that the analyzed snakes, which inhabit the regions of Greater Victoria and the mountainous region of the State of Espírito Santo have high concentrations of the microelements Zn and Fe.(AU)

Effects of humic acids from landfill leachate on plants: An integrated approach using chemical, biochemical and cytogenetic analysis.

Biological process treatment of landfill leachate produces a significant amount of sludge, characterized by high levels of organic matter from which humic acids are known to activate several enzymes of energy metabolism, stimulating plant growth. This study aimed to characterize humic acids extracted from landfill sludge and assess the effects on plants exposed to different concentrations (0.5, 1, 2 and 4 mM C L-1) by chemical and biological analysis, to elucidate the influence of such organic material and minimize potential risks of using sludge in natura. Landfill humic acids showed high carbon and nitrogen levels, which may represent an important source of nutrients for plants. Biochemical analysis demonstrated an increase of enzyme activity, especially H+-ATPase in 2 mM C L-1 landfill humic acid. Additionally, cytogenetic alterations were observed in meristematic and F1 cells, through nuclear abnormalities and micronuclei. Multivariate statistical analysis provided integration of physical, chemical and biological data. Despite all the nutritional benefits of humic acids and their activation of plant antioxidant systems, the observed biological effects showed concerning levels of mutagenicity.