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11.
In general, tropical rivers have a great impact on human activities. Bioaccumulation of toxins is a worldwide problem nowadays and has been, historically, overlooked by the supervisory authorities. This study evaluated cytogenotoxic effects of Guaribas river (a Brazilian river) water during dry and rainy seasons of 2014 by using the Allium cepa test system. The toxicogenetic variables, including root growth, mitotic index, and chromosomal aberrations, were analyzed in meristematic cells of A. cepa exposed to water samples taken from the up-, within, and downstream of the city Picos (state: Piauí). The physical-chemical parameters were also analyzed to explain water quality and possible anthropogenic action. Additionally, the presence of heavy metals was also analyzed to explain water quality and possible damaging effects on eukaryotic cells. The results suggest that the river water exerted cytotoxic, mutagenic, and genotoxic effects, regardless of the seasons. In addition, Guaribas river presented physico-chemical values outside the Brazilian laws, which can be a characteristic of human pollution (domestic sewage, industrial, and local agriculture). The genetic damage was positively correlated with higher levels of heavy metals. The pollution of the Guaribas river water may link to the chemical contamination, including the action of heavy metals and their impacts on genetic instability in the aquatic ecosystem. In conclusion, necessary steps should be taken into account for further toxicogenetic studies of the Guaribas river water, as it has an influence in human health of the same region of Brazil.  相似文献   
12.
The State of Minas Gerais represents one of Brazil's most outstanding mining resources. The contamination of river waterfrom kaolin processing activities may be harmful to people inthe way of slow but chronic poisoning. On the other hand, the discharge of untreated or inadequately treated domestic sewage into aquatic environments can also cause deleterious effects to the health. However, no reliable figures are available for pollutant occurrences in river water. This draws attention to thevery precarious situation that exists with respect to pollutionby organic and inorganic toxic wastes, especially with respect to humans and fauna in all its expressions. Thus, with the purpose of establishing a preliminary report to trace out industrialisation outcomes, samples of river water, vegetation and fish were collected and analysed to detect pollutant inputs.The concentration of metals was determined in suspended particle,vegetation and fish, while those of nitrite, nitrate, phosphateand chloride were determined in river water samples. The concentration of dissolved oxygen (DO) was measured in river water at the time of collection. Chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were also determined. Metalinputs in the samples analysed appeared to be related to effluentdischarges into the rivers. The suspended particles showed highconcentrations (in mg kg-1) of zinc (62 600) and aluminium(559 000), while vegetation samples collected near rivers wereheavily contaminated with iron (7680). The fishes examined werecontaminated with chromium (1.5 mg kg-1). In general, the concentrations of nitrite, nitrate, chloride, phosphate and BOD in river water were lower than the maximum values established bythe Brazilian Environmental Standards.  相似文献   
13.
Journal of Polymers and the Environment - Anthocyanins (ACNs) are natural pigments broadly used in the food industry due to their color, antioxidant, and antimicrobial properties, however, these...  相似文献   
14.
Sodium metabisulfite is used in marine shrimp harvesting to prevent the occurrence of black spots. Shrimps are soaked in a sodium metabisulfite solution in ice, which is disposed of in sewages that run into marine canals, creating an environmental hazard. This study evaluates the toxicity and mutagenicity caused by sodium metabisulfite in sea waters and sediments collected in a shrimp farm in Cajueiro da Praia (Luis Correia), state of Piauí, Brazil, using the Allium cepa assay. Water and sediment samples were collected in the dry and in the rainy seasons, in three sites: upstream the shrimp farm (Site 1), at the point sodium metabisulfite is discharged (Site 2), and 100 m downstream the farm (Site 3). Three sample dilutions were used (50%, 25% and 10%) for all samples. A negative control (well water) and a positive control (copper sulfate 0.0006 mg mL−1) were used in each experiment. At the end of the 72-h exposure period, onion roots were measured and removed. Mutagenicity analysis included the determination of mitotic index, chromosomal aberrations and the detection of micronuclei; analysis of root size and mitotic index were used as an index of toxicity. The A. cepa assay revealed that the water and sediments samples collected in the Piauí coast contaminated with sodium metabisulfite induce toxicity. The results demonstrate that the assay may be used as a regular tool in the analysis of water parameters in shrimp farms in the coast of Piauí state, and in strategies to preserve the region’s marine ecosystem.  相似文献   
15.
Copper compounds have been intentionally introduced into water bodies as aquatic plant herbicides, algicides and molluscicides. Copper-based fertilizers and fungicides have been widely used in agriculture as well. Despite the fact that copper is an essential element for all biota, elevated concentrations of this metal have been shown to affect a variety of aquatic organisms. Nonetheless, comparative studies on the susceptibility of different freshwater species to copper compounds have seldom been performed. This study was conducted to compare toxicity of copper-based pesticides (copper oxychloride, cuprous oxide and copper sulfate) to different freshwater target (Raphidocelis subcapitata, a planktonic alga and Biomphalaria glabrata, a snail) and non-target (Daphnia similis, a planktonic crustacean and Danio rerio, a fish) organisms. Test water parameters were as follows: pH = 7.4 +/- 0.1; hardness 44 +/- 1 mg/l as CaCO3; DO 8-9 mg/l at the beginning and > 4 mg/l at the end; temperature, fish and snails 25 +/- 1 degrees C, Daphnia 20 +/- 2 degrees C, algae 24 +/- 1 degrees C. D. similis (immobilization), 48-h EC50s (95% CLs) ranging from 0.013 (0.011-0.016) to 0.043 (0.033-0.057) mg Cu/l, and R. subcapitata (growth inhibition), 96-h IC50s from 0.071 (0.045-0.099) to 0.137 (0.090-0.174) mg Cu/l, were the most susceptible species. B. glabrata (lethality), 48-h LC50s from 0.179 (0.102-0.270) to 0.854 (0.553-1.457) mg Cu/l, and D. rerio (lethality), 48-h LC50s 0.063 (0.045-0.089), 0.192 (0.133-0.272) and 0.714 (0.494-1.016) mg Cu/l, were less susceptible than Daphnia to copper-based pesticides. Findings from the present study therefore suggest that increased levels of copper in water bodies is likely to adversely affect a variety of aquatic species.  相似文献   
16.
Environmental Science and Pollution Research - In recent years, research has been conducted in search of alternative adhesives that are less harmful to human health and the environment. Cardanol...  相似文献   
17.
Environmental Science and Pollution Research - In this study, binary and ternary mixed metal oxide anodes of Ti/RuO2–Sb2O4 and Ti/RuO2–Sb2O4–TiO2 were prepared using two different...  相似文献   
18.
The risk of disease transmission can affect female mating rate, and thus sexual conflict. Furthermore, the interests of a sexually transmitted organism may align or diverge with those of either sex, potentially making the disease agent a third participant in the sexual arms race. In Drosophila melanogaster, where sexual conflict over female mating rate is well established, we investigated how a common, non-lethal virus (sigma virus) might affect this conflict. We gave uninfected females the opportunity to copulate twice in no-choice trials: either with two uninfected males, or with one male infected with sigma virus followed by an uninfected male. We assessed whether females respond behaviorally to male infection, determined whether male infection affects either female or male reproductive success, and measured offspring infection rates. Male infection status did not influence time to copulation, or time to re-mating. However, male infection did affect male reproductive success: first males sired a significantly greater proportion of offspring, as well as more total offspring, when they were infected with sigma virus. Thus viral infection may provide males an advantage in sperm competition, or, possibly, females may preferentially use infected sperm. We found no clear costs of infection in terms of offspring survival. Viral reproductive success (the number of infected offspring) was strongly correlated with male reproductive success. Further studies are needed to demonstrate whether virus-induced changes in reproductive success affect male and female lifetime fitness, and whether virus-induced changes are under male, female, or viral control.  相似文献   
19.
The increasing concern regarding the preservation of soil quality suggests the adoption of quality reference values as a first step in environmental monitoring actions. In this context, the objective of this study was to establish soil quality reference values for Al, Zn, Mn, Cd, Fe, Pb, Ni, Cr, and Cu and to correlate several soil properties with the occurrence of these elements in the hillslope region of Rio de Janeiro State. Sixty-two samples were collected at depths of 0–20 and 20–40 cm and analyzed using the USEPA method 3051A. After clustering analysis, the samples were separated into three groups. Classification functions were obtained based on the variables pH - Mg - Fe - Mn, i.e., the variables that were best related to heavy metal content. We determined to establish the quality reference values for the 75th percentile of the three groups. The relief forms of the area, which facilitate the transport of soil fine-particle fractions and accumulation in lowlands, were revealed to be one of most important factors in understanding the distribution of soil heavy metals.  相似文献   
20.
Atmospheric aerosols of four aerodynamic size ranges were collected using high volume cascade impactors in an extremely busy roadway tunnel in Lisbon (Portugal). Dust deposited on the tunnel walls and guardrails was also collected. Average particle mass concentrations in the tunnel atmosphere were more than 30 times higher than in the outside urban background air, revealing its origins almost exclusively from fresh vehicle emissions. Most of the aerosol mass was concentrated in submicrometer fractions (65%), and polycyclic aromatic hydrocarbons (PAH) were even more concentrated in the finer particles with an average of 84% of total PAH present in sizes smaller than 0.49 μm. The most abundant PAH were methylated phenanthrenes, fluoranthene and pyrene. About 46% of the total PAH mass was attributed to lower molecular weight compounds (two and three rings), suggesting a strong influence of diesel vehicle emissions on the production of local particulate PAH. The application of diagnostic ratios confirmed the relevance of this source of PAH in the tunnel ambient air. Deposited dust presented PAH profiles similar to the coarser aerosol size range, in agreement with the predominant origin of coarser aerosol particles from soil dust resuspension and vehicle wear products.  相似文献   
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