Results 1 - 3 of 3
Results 1 - 3 of 3. Search took: 0.014 seconds
|Sort by: date | relevance|
[en] Metallic elements found in the aquatic environment may originate in areas where petroleum is refined and vessels are maintained and repaired. This study aims to assess contamination caused by nickel (Ni), lead (Pb), and vanadium (V) in sediment of the Lagoa dos Patos estuary (RS, Brazil) and to evaluate them as indicators of areas under the influence of petroleum products and antifouling paints. Surface sediments were collected in summer and in winter in areas of marinas, shipyards, refinery, and a control station. High Pb and V concentrations in shipyards and at the Yacht Club showed that some organisms may be affected by toxicity. High Pb results of the index of geoaccumulation (Igeo) were found at the Yacht Club and shipyards. Al, Ni, and V had similar distribution in the sediment in both seasons. Ni and V had high relation in winter at the Yacht Club and at the Santos Shipyard, thus suggesting that these elements come mainly from petroleum products. The same happened to the relations between Pb and V, as well as Pb and Ni at the Santos Shipyard. These elements are employed as useful tools as indicators to identify places with moderate to high localized anthropogenic inputs of petroleum derivatives and antifouling paints.
[en] On the basis of the assumption that legally protected areas are created to maintain environmental quality that, in turn, is indispensable for quality of life, this study aims to evaluate the soil conditions in protected areas that are located near urban regions by using ecotoxicological assays and chemical analysis. The study was carried out using surface soil samples collected from seven protected areas in southern Brazil. For the protected area to be considered “clean,” the results of the ecotoxicological tests should be within the criteria accepted for negative control according to standardized protocols, and the concentration of chemical elements should be below the maximum levels allowed by Brazilian law. On the basis of the criteria adopted for ecotoxicological assays and chemical analysis, soil from only two of the seven protected areas (28.6%) met the criteria for being considered “clean.” This probably reflects the influence of anthropogenic activities within the protected areas, demonstrating drawbacks of delimitation and management. The strategy used in this study could be used to assess the anthropogenic impact on protected areas in other parts of the world.
[en] In large urban centers, the toxicity of metal mixtures may be enhanced by physicochemical factors and environmental variables, including pH. Rio Grande, a municipality located in the extreme south of Brazil, has soils with high levels of contamination due to urban and industrial activities and a high prevalence of acid rain events. Previous studies have shown that contact with elutriate of these soils can cause physiological and reproductive changes. Thus, the objective of the present study was to evaluate, through animal experimentation, the effects of a metal-contaminated soil, acidified by hydrofluoric acid at two different pH values (5.2 and 3.6), on the health of offspring of rats exposed during gestation and lactation. Female Wistar rats were gavaged daily for 42 days (gestation and breastfeeding) with soil elutriate contaminated with metals, using solvent with different pH values (6.0, 5.2, and 3.6). The following parameters were evaluated in their offspring: body and organ weight, length, appearance of developmental characteristics, and swimming. Experimental groups in which the progenitors were exposed to the solution at pH 3.6 exhibited a delayed increase in weight as well as motor deficit, with a decreased weight (onset) and length (beginning and end), while exposure in association with soil was an aggravating factor for the damages to the body. Exposure to the solution at pH 5.2 decreased the initial weight of the animals, impaired some parameters of weight development, and caused motor deficit on the 14th day. These novel findings reveal that the exposure of progenitors to environmental stressors can compromise the health of the offspring. Special attention should be given to populations living in areas with high prevalence of acid rain.