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441.
This article discusses the experience of the map of conflicts related to environmental injustices and health in Brazil and its potential contribution to international movements for environmental justice. Inventories and maps of environmental injustices are important instruments of struggle against injustice and racism, since they increase the visibility of populations, whose lives are threatened. The Brazilian map is published online since 2010 and was an initiative of FIOCRUZ, a public health and academic institution, and the NGO FASE, in cooperation with the Brazilian Network of Environmental Injustice (RBJA), created in 2001. Environmental justice arised in Brazil as a field of reflection and mobilization, and as a rallying point to identify the struggle of several groups and entities, such as rural and urban grassroots movements, indigenous peoples, traditional populations, and peasants affected by different hazards and risks, as well as environmentalists, trade unions, and scientists. Currently, the map has 570 emblematic environmental conflicts in all regions of Brazil. Many economic activities are causing the conflicts such as mining expansion, oil and gas extractions, infrastructure (roads, mega-dams), agribusiness, and pesticide pollution, often with the support of governmental institutions.  相似文献   
442.
A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of 14C-labeled substances in soil–plant–atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between 14C-emissions from soil surfaces and 14C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate – using the two-chamber-lysimeter-test-system – are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil–plant-systems. Mineralization of 14C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide 14C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules.  相似文献   
443.
The reactivity of paclobutrazol (PBZ, a plant growth retardant) with a Yellow Ultisol and a Vertisol from the semiarid northeast region of Brazil was evaluated through batch sorption experiments and modeling. Although not instantaneous, the sorption kinetic of PBZ (pure and formulated) was fast (a few hours) in both soils. The sorption kinetics were well described by a second-order (dS(t)/dt=k(2)(S(e2)-S(t))(2)) but not by a first-order model. The sorption isotherms were found to be linear and the calculated K(D) values were 8.8 +/- 0.11 and 7.4 +/- 0.2 L kg(-1) for pure PBZ in the Ultisol and the Vertisol, respectively. The corresponding K(OC) values were 1275 +/- 34 (logK(OC) = 3.11) and 1156 +/- 49 (logK(OC) = 3.06) L kg(-1), respectively. Considering the very different texture of the two soils and the similar K(OC) values determined, these results showed that in both soils, the sorption of PBZ is dominantly controlled by organic matter, although some interactions of PBZ with iron oxides (goethite) were observed in the Ultisol. Based on these sorption parameters a low leachability potential of PBZ in soils is anticipated, as they correspond to a groundwater ubiquity score (GUS) ranging from 2.0 to 2.7, i.e., moderately to not mobile, in contradiction with the actual groundwater situation in Brazil. This work stresses the need to evaluate and predict the risk associated with aquifer contamination by this widely used plant growth regulator.  相似文献   
444.
Major ion, trace element, and stable isotope analyses were performed on groundwater samples collected during November 2005 and 2006 in Chia-Nan plain of southwestern Taiwan to examine As mobilization in aquifers. The high concentrations of As, Fe and Mn in the groundwater is consistent with low Eh values (under moderately reduced state). Moreover, the observed Na/Cl and SO(4)/Cl molar ratios in groundwater demonstrate the influence of seawater intrusion. Seawater intrusion could provide required electron acceptors (i.e., SO(4)) for bacterial sulfate reduction and promote reducing conditions that are favorable for As mobilization. The concurrent increases in the concentrations of Fe and Mn from 2005 to 2006 may be caused by bacterial Fe(III) and Mn(IV) reduction. Geochemical modeling demonstrate that As(III) is the dominant As species and the presence of Fe-bearing carbonates, sulfides, and oxide phases may locally act as potential sinks for As. Mud volcano fluids were also collected and analyzed to assess the possible source of As in the Chia-Nan plain groundwater. The oxygen and hydrogen isotopic signatures indicate that the As-rich mud volcano fluids may have been modified by chemical exchange with (18)O-rich crustal rocks and possibly originated from mixing of deep brines with circulating meteoric water. Thus As in the Chia-Nan plain groundwater may have been evolved from deep crustal fluids or rock sources. The hydrogeochemistry and widespread As enrichment in groundwater of Chia-Nan plain result from multiple processes, e.g., de-watering of deep crustal fluids, seawater intrusion, and biogeochemical cycling of Fe, As, and S in alluvial sediments.  相似文献   
445.
Groundwaters have been collected from deltaic areas of West Bengal (Chakdaha and Baruipur blocks) to record their hydrogeochemical characteristics, and to verify the mechanism of arsenic (As) release. The data reveals that shallow (<70 m) groundwaters in both areas are of Ca-Mg-HCO(3) type; however deeper (>70 m) groundwaters in Baruipur areas are slightly enriched with Na, Cl and SO(4), indicating possible saline water intrusion. The groundwater is anoxic (mean Eh: -124 and -131 mV) with high levels of As (mean: 116 and 293 mug/L), Fe (mean: 4.74 and 3.83 mg/L), PO(4) (mean: 3.73 and 3.21 mg/L) and Mn (mean: 0.37 and 0.49 mg/L), respectively for Chakdaha and Baruipur areas. The observed values of As and bicarbonate (mean: 409 and 499 mg/L) in the shallow aquifer are indicative of redox processes (e.g., oxidation of organic matter) favouring the release of As. Moreover, the presence of DOC in the shallow aquifer suggests that organic matter is young and reactive, and may actively engage in redox driven processes. Our study further confirms that both Fe- and Mn-reduction processes are the dominant mechanisms for As release in these groundwaters.  相似文献   
446.
Lake Ontario and St. Lawrence River (LOSL) wetland bird abundance and diversity are greatly influenced by lake and river hydrology. Our study used an interdisciplinary ecosystem approach, blending avian and plant ecology, ecohydraulic, statistical ecology and modelling to evaluate potential impacts of water level fluctuations on indicator species representative of the wetland breeding bird assemblages in the entire LOSL freshwater system. Multi-year (2000–2003) bird surveys captured bird distribution and density in wetland habitats under varying degrees of water inandation, depth and fluctuation. Analyses revealed strong associations between estimated breeding pair densities and plant communities, water depth, and degree of water level fluctuation during the breeding season for a suite of wetland bird species using marsh, wet meadow, shrub swamp and treed swamp habitats. These quantitative associations were used to develop wetland bird performance indicators for use in a LOSL water regulation review study. Several bird species also nest at or near the water surface and are thus vulnerable to nest flooding or stranding. Changes to the seasonal hydrology of Lake Ontario and St. Lawrence River that result in an increased frequency or magnitude of these nest failure events may have a significant impact on regional population sustainability. Long term nest record databases were analyzed to create nesting flooding and stranding probability equations based on water level increases and decreases during the breeding season. These species-specific nesting relationships were incorporated into a reproduction index.Many breeding bird species were strongly associated with specific wetland plant communities. Predicted habitat suitability, as measured by estimated breeding pair density, can also change significantly within a specific wetland plant community based solely on changes in water depth during the breeding season. Three indicator species, Black Tern, Least Bittern and Virginia Rail were selected as key environmental performance indicators for alternate regulation plan comparisons.Water regulation criteria should be such that the long term diversity and abundance of wetland plant communities and frequency of spring flooding in marsh habitats during breeding are not reduced. Magnitude and frequency of water level change during the nesting season (May–July) can also adversely impact reproductive success of many wetland bird species. As such, regulation criteria that increase the seasonal magnitude and frequency of water level change may be detrimental to the long term viability of certain regional breeding bird populations.  相似文献   
447.
This analysis examines the ability of previous offenses to predict future high-risk offenses, and similarly, the ability of crashes to predict future high-risk crashes, using the complete driver history data (up to 9 years) for a set of young Michigan subjects. As expected, those with previous ticketed offenses or reported crashes are at greater risk for future offenses or crashes; with a previous-year serious offense doubling the odds of serious offenses during the subsequent year, and a previous-year at-fault crash increasing the odds of subsequent-year at-fault crashes by nearly 50%. There is modest evidence that serious offenses and at-fault crashes may better predict subsequent behavior in females and in more experienced drivers. This latter finding is also evidenced by the fact that records of these young drivers are less predictive of subsequent driving history than is true for records of all drivers in general found in other studies. This suggests that, in the early stages of driving, offenses and crashes are, at least in part, attributable to inexperience, and hence, characteristic of all beginning drivers.  相似文献   
448.

Goal, Scope, and Background

According to European legislation, an environmental risk assessment of veterinary pharmaceuticals for dung beetles is required if the substance is a parasiticide for the treatment of pasture animals. However, the demonstration of the environmental safety of those substances for dung beetles is strongly hampered by the fact that no standardized test system is available so far. Therefore, starting with recommendations from the SETAC advisory group DOTTS (Dung Organism Toxicity Test Standardization), a test system using the widespread temperate dung beetle species Aphodius constans was developed.

Methods

Using experiences gained at the University of Montpellier (e.g. in field studies) and in other terrestrial tests, details of culturing and testing of A. constans were investigated in a project sponsored by the German Environment Protection Agency (UBA). Basically, the survival of young larvae of A. constans exposed to the test substance spiked into formulated (i.e. dried, grounded and re-wetted) or fresh dung is measured over a period of three weeks. Using the model substance dimethoate (an insecticide required as positive control in tests with the predatory mite Hypoaspis aculeifer) the suitability of the new test was checked. Afterwards, the new test method was used to determine the toxicity of four common veterinary pharmaceuticals (ivermectin, dicyclanil, moxidectin, praziquantel) in formulated and fresh dung. Finally, the effects of ivermectin on the dung beetles were determined in a test using fresh dung from treated cattle.

Results and Conclusions

For Dmethoate LC50-values were found in a range of 1–3 mg a.s./kg dung (dew.), depending on the dung type. Praziquantel did not show eirecis in the tested concentration range (i.e. up to 1000 mg a.s./kg Dung (DW). The LC50-values of the other three pharmaceuticals were very low (<6 mg a.s./kg dung (DW)). With the exception of Dicyclanil no differences between formulated and fresh dung were identified. In the case of ivermectin the LC50-value were even lower: about 0.5 mg a.s./kg dung (DW). No differences between the results of test in which the substance was spiked into dung and those tests which were performed with dung from treated cattle were found. These results prove the sensitivity as well as the robustness of this test method.

Recommendations and Perspectives

Based on the experiences reported here, it is recommended to standardize this test in an international ring test so that it can be incorporated in the risk assessment process for veterinary pharmaceuticals as described in the currently developed international registration guidelines.  相似文献   
449.
Since the air pollution as measured by stationary monitoring stations is a poor indicator of the population exposure, personal monitors are indispensible to health effects studies. This article reviews the current research on the development of personal monitors. Although most of the analytical methods reviewed in this study appear to be sensitive to the levels of the target pollutants NO2, SO2, and O3 generally encountered in indoor and outdoor air, they lack the desired performance characteristics for a personal monitoring device, such as user safety and ease of operation, weight, and maintenance. Electrochemical transducers/sensors, which have not yet been exploited, are attractive candidates for the application to personal monitoring. This technique has an added feature of generating real-time measurements. A few research models and commercially attractive devices that can be used in field studies are included.  相似文献   
450.
Data were collected from managers in 24 nations/territories on work locus of control (LOC), individualism–collectivism (I–C), and well‐being (job satisfaction, absence of psychological strain, and absence of physical strain). There were significant mean differences across samples on all five of these measures, and consistent with our hypothesis, at the ecological or sample mean level well‐being was associated with an internal locus of control. However, contrary to our hypothesis, well‐being was not associated with I–C, despite a strong correlation between I–C and LOC. Findings at the ecological level were consistent with the literature concerning the salutary effects of control on well‐being. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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