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1.
An estimate of heavy metals emissions to the atmosphere due to the projected changes in the Brazilian energy generation fuel matrix is presented. Present use of fossil fuel combustion for energy production is projected to increase from the present 14.5% to 29.6% of the total energy generation in Brazil in 2005. Most of this increase will be based on coal- and natural-gas-burning plants. The changes will result in an increase of about 100% in the average emissions (in tons year−1) of As (9.4 to 17.7), Cr (7.0 to 16.6) and Hg (2.4 to 4.1), 50% of Cd (1.2 to 1.8), and 20% of Ni (101 to 123) and Pb (23.3 to 29.9). Although relatively small for most heavy metals when compared to other industrial sources, the changes in the energy matrix will be particularly important for Hg, reaching a maximum emission of 12 tons (t) year−1, representing 15% of the total emissions of Hg to the atmosphere in Brazil. The use of Brazilian coals and the location of most coal-burning plants in a relatively small region in the south of the country strongly suggest that monitoring programs should be implemented during the building of the new plants. At a regional level the expected increase in Hg emissions to the atmosphere due to coal burning in Brazil, although small relative to North America and Europe, will equal the total amount estimated for South and Central America.  相似文献   

2.
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is...  相似文献   

3.
Based on production data published by the Brazilian Mineral Water Producers Association, bottled mineral waters were bought at the market, covering, at least, 50% of the annual production of each Brazilian geographical region. 228Ra, 226Ra and 210Pb were analyzed and the weighted mean values obtained for Brazilian mineral waters were 0.097, 0.027 and 0.066 Bq l-1 respectively. Individual effective dose rate estimates due to ingestion of mineral water in Brazil were of the order of 10-100 microSv yr-1, depending on the geographical region. Based on the available data, it was also possible to evaluate the per caput effective dose rate and the highest value obtained was 4.3 microSv yr-1 for the northern region.  相似文献   

4.
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   

5.
Brazil is considered one of the world’s leading producers of biofuels given the predominance of ethanol fuel in its energy matrix. However, despite the prominence of Brazil in ethanol production, the vast majority of biodiesel production plants in Brazil use methanol instead of ethanol as the alcohol for transesterification reaction, as is generally the case in the rest of the world. The aim of this paper is therefore to examine the transesterification process in the Brazilian biodiesel production in terms of sustainability. In this regard, it was necessary to evaluate the way in which the industrial process is currently carried out, the role of government incentives or subsidies for the use of ethanol to produce biodiesel, and the investments of companies in technology development for the same purpose. This study presents indications that the development of the biodiesel market in Brazil is still oriented toward a production model which is inconsistent with the environmental and social aspects of sustainability.  相似文献   

6.

Southern Amazonia is the first region of Brazil’s Amazon area to be exposed to intensive conversion to agriculture and ranching. This conversion emits greenhouse gases from the carbon stock in the biomass and soils of the previous vegetation. Quantifying these carbon stocks is the first step in quantifying the impact on global warming from this conversion. This review is limited to information on Brazilian Amazonia’s carbon stocks. It indicates large amounts of carbon at risk of emission in both biomass and soils, as well as considerable uncertainty in estimates. Reducing uncertainty is a priority for research but the existence of uncertainty must not be used as an excuse for delaying measures to contain deforestation. The magnitude of carbon stocks is proportional to greenhouse gas emissions per hectare of deforestation and consequently to impact on global climate.

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7.
The spatial distribution and behaviour of the global fallout (137)Cs in the tropical, subtropical and equatorial soil-plant systems were investigated at several upland sites in Brazil selected according to their climate characteristics, and to the agricultural importance. To determine the (137)Cs deposition density, undisturbed soil profiles were taken from 23 environments situated between the latitudes of 02 degrees N and 30 degrees S. Sampling sites located along to the equator exhibited (137)Cs deposition densities with an average value of 219Bqm(-2). Extremely low deposition densities of 1.3Bqm(-2) were found in the Amazon region. In contrast, the southern part of Brazil, located between latitudes of 20 degrees S and 34 degrees S, exhibited considerably higher deposition densities ranging from 140Bqm(-2) to 1620Bqm(-2). To examine the (137)Cs soil-to-plant transfer in the Brazilian agricultural products, 29 mainly tropical plant species, and corresponding soil samples were collected at 43 sampling locations in nine federal states of Brazil. Values of the (137)Cs concentration factor plant/soil exhibited a large range from 0.020 (beans) to 6.2 (cassava). Samples of some plant species originated from different collecting areas showed different concentration factors. The (137)Cs content of some plants collected was not measurable due to a very low (137)Cs concentration level found in the upper layers of the incremental soils. Globally, the soil-to-plant transfer of (137)Cs can be described by a logarithmic normal distribution with a geometric mean of 0.3 and a geometric standard deviation of 3.9.  相似文献   

8.
Public authorities must make decisions about energy, and the risks of alternative strategies need to be calculated including health and environmental costs. Information from various sources must be organized into a logical framework for comparing impacts. This must include the widest practicable range of health and environmental damage — public-health impact of pollution, role of accidents, disease and hazardous materials in the workplace, and odds for catastrophes. It must put each part of the energy cycle into perspective-giving particular attention to uncertainties in knowledge - to convey what is known, what is uncertain, and the importance of each factor in the overall picture. This paper gives examples of the use of health-impact assessment by decisionmakers: (1) comparative risk assessment of the health effects of coal and nuclear fuel cycles used in nuclear power plant siting and licensing hearings, and (2) health risks of acid deposition and other air-transported pollutants, carried out as part of an assessment for the U.S. Congress Office of Technology Assessment.  相似文献   

9.
A global monitoring system for atmospheric xenon radioactivity is being established as part of the International Monitoring System to verify compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The isotopic activity ratios of (135)Xe, (133m)Xe, (133)Xe and (131m)Xe are of interest for distinguishing nuclear explosion sources from civilian releases. Simulations of light water reactor (LWR) fuel burn-up through three operational reactor power cycles are conducted to explore the possible xenon isotopic signature of nuclear reactor releases under different operational conditions. It is studied how ratio changes are related to various parameters including the neutron flux, uranium enrichment and fuel burn-up. Further, the impact of diffusion and mixing on the isotopic activity ratio variability are explored. The simulations are validated with reported reactor emissions. In addition, activity ratios are calculated for xenon isotopes released from nuclear explosions and these are compared to the reactor ratios in order to determine whether the discrimination of explosion releases from reactor effluents is possible based on isotopic activity ratios.  相似文献   

10.
(14)C specific activities were measured in grass samples collected around Brazilian nuclear power reactors. The specific activity values varied between 227 and 299 Bq/kg C. Except for two samples which showed (14)C specific activities 22% above background values, half of the samples showed background specific activities, and the other half had a (14)C excess of 1-18%. The highest specific activities were found close to the nuclear power plants and along the main wind directions (NE and NNE). The activity values were found to decrease with increasing distance from the reactors. The unexpectedly high (14)C excess values found in two samples were related to the local topography, which favors (14)C accumulation and limits the dispersion of the plume. The results indicate a clear (14)C anthropogenic signal within 5 km around the nuclear power plants which is most prominent along northeastwards, the prevailing wind direction.  相似文献   

11.
This paper explores China’s role in deforestation in Latin America. Brazil’s Amazon region contains vast natural resources including land, timber, minerals and hydroelectric potential. China’s strong economy and large demands relative to domestic supplies of these resources mean that China has become Brazil’s largest trading partner, primarily for natural resources. The paper examines how China influences deforestation in Brazilian Amazonia in a variety of ways, including through the direct influence of Chinese enterprises through land purchases and other mechanisms. This paper finds that the rapid rise in exports of soy and beef products to China are two of the major drivers of Amazonian deforestation in Brazil. The paper further argues that Chinese purchases of agricultural and forest land and Chinese imports of commodities such as timber and aluminum also cause environmental impacts in Amazonia. Chinese financing and investment in Amazonian infrastructure such as railways and mineral processing facilities have additional impacts.  相似文献   

12.
The goal of this work was to establish comparisons among environmental degradation in different areas from Southern Spain (Gulf of Cádiz) and Brazil (Santos and S?o Vicente estuary), by using principal component analyses (PCA) to integrate sediment toxicity (amphipods mortality) and chemical-physical data (Zn, Cd, Pb, Cu, Ni, Co, V, PCBs, PAHs concentrations, OC and fines contents). The results of PCA extraction of Spanish data showed that Bay of Cádiz, CA-1 did not present contamination or degradation; CA-2 exhibited contamination by PCBs, however it was not related to the amphipods mortality. Ría of Huelva was the most impacted site, showing contamination caused principally by hydrocarbons, in HV-1 and HV-2, but heavy metals were also important contaminants at HV-1, HV-2 and HV-3. Algeciras Bay was considered as not degraded in GR-3 and -4, but in GR-3' high contamination by PAHs was found. In the Brazilian area, the most degraded sediments were found in the stations situated at the inner parts of the estuary (SSV-2, SSV-3, and SSV-4), followed by SSV-6, which is close to the Submarine Sewage Outfall of Santos - SSOS. Sediments from SSV-1 and SSV-5 did not present chemical contamination, organic contamination or significant amphipod mortality. The results of this investigation showed that both countries present environmental degradation related to PAHs: in Spain, at Ría of Huelva and Gudarranque river's estuary areas; and in Brasil, in the internal portion of the Santos and S?o Vicente estuary. The same situation is found for heavy metals, since all of the identified metals are related to toxicity in the studied areas, with few exceptions (V for both Brazil and Spain, and Cd and Co for Brazilian areas). The contamination by PCBs is more serious for Santos and S?o Vicente estuary than for the investigated areas in Gulf of Cádiz, where such compound did not relate to the toxicity.  相似文献   

13.
Nuclear power plants release 14C during routine operation mainly as airborne gaseous effluents. Because of the long half-life (5730 years) and biological importance of this radionuclide (it is incorporated in plant tissue by photosynthesis), several countries have monitoring programs in order to quantify and control these emissions. This paper compares the activity of 14C in soils taken within 1 km from a Brazilian nuclear power plant with soils taken within a reference area located 50 km away from the reactor site. Analyses of total carbon, δ13C and 137Cs were also performed in order to understand the local soil dynamics. Except for one of the profiles, the isotopic composition of soil organic carbon reflected the actual forest vegetation present in both areas. The 137Cs data show that the soils from the base of hills are probably allocthonous.  相似文献   

14.
In Brazil, there are few studies investigating the performance and guidelines parameters of solar light pipes from the national perspective. This paper aims to analyse the performance of a solar light pipe prototype installed in a test house in the city of Curitiba/PR, Brazil and to indicate a set of parameters for the design of solar light pipes for the Brazilian social housing context. The performance of a solar light pipe provided with different lighting devices to control and redirect light was analysed. The best performance for diffusers was obtained during partially covered skies. Light redirection devices presented the best efficiency during clear sky conditions with direct sunlight, on working-planes closer to the prototype. The developed prototype with the lighting control devices produced a considerably enhanced lighting performance, complementing natural lighting in indoor environment. Based on the results, recommendations and guidelines to enhance solar light pipe configurations are proposed.  相似文献   

15.
The main purpose of this paper is to use data envelopment analysis (DEA) as a support tool to establish a relative eco-efficiency measure for the different bioethanol transportation modes and to prioritize these different modes according to these figures. From a review of previous studies, we selected a set of attributes to be considered in DEA, and then experts were consulted about the importance of these attributes for this type of analysis in Brazil. To quantify the attributes, we established indicators and submitted them to DEA to evaluate the relative eco-efficiency to each available transportation mode for the case studied. The use of DEA established the guidelines to improve the transportation modes that were not considered 100?% relatively eco-efficient. These improvements could be achieved considering the percentage, reduction or growth for each of the attributes in the selected transportation mode. The proposed approach can help the Brazilian government to develop a plan to improve the bioethanol transportation infrastructure and can be used to propel short-term improvements in the highway transport of bioethanol, which could be useful given the Brazilian transportation context.  相似文献   

16.
Brazil is a central place in the international agricultural markets and this fact has been demanding environmentally oriented agricultural practices by Brazilian farmers and professionals involved in the agricultural market chain. A concise and structured questionnaire was applied to obtain the environmental perception of a group of Brazilian farmers in a town of the south Minas Gerais state, using herbicides as the topic for a case study. A highly variable opinion about taking the environment into account when choosing the most appropriate herbicide was found. Anyway, efficacy has been indicated as the most important factor when choosing an herbicide, followed by the environment and price. The outcomes from the questionnaires, i.e. the insufficient conception and importance given to environment when choosing the herbicide, motivated the creation of a teaching-learning model for the nonformal environmental education using the concept of socio-ecological resilience. This routine puts in practice the resilience thinking currently invoked as a major tool to achieve the conservation of the socio-ecological system, as well as it is complimentary to the outcome-oriented optimization for conservation theory. For the case study about farmers and the use of herbicides, we conclude that a complex reasoning and, ultimately, pro-environmental actions can be improved after experiencing the recommended model for environmental education.  相似文献   

17.
In order to contribute to a future waste management policy related to the presence of technologically enhanced natural occurring radioactive material (TENORM) in the Brazilian petroleum industry, the present work presents the chemical composition and the (226)Ra and (228)Ra content of sludge and scales generated during the offshore E and P petroleum activities in the Campos Basin, the primary offshore oil production region in Brazil. The (226)Ra and (228)Ra content on 36 sludge and scales samples were determined by gamma-spectrometry. Based on X-ray diffractometry results, a chemical analysis schema for these samples was developed. The results have shown that scales are 75% barium and strontium sulfates, with a mean (226)Ra and (228)Ra content of 106 kBq kg(-1) and 78 kBq kg(-1), respectively. On the other hand, sludge samples have a much more complex chemical composition than the scales. The (226)Ra and (228)Ra content in sludge also varies much more than the content observed in the scales samples and ranged from 0.36 to 367 kBq kg(-1) and 0.25 to 343 kBq kg(-1), respectively.  相似文献   

18.
The problem of identifying the provenance of unknown nuclear material in the environment by multivariate statistical analysis of its uranium and/or plutonium isotopic composition is considered. Such material can be introduced into the environment as a result of nuclear accidents, inadvertent processing losses, illegal dumping of waste, or deliberate trafficking in nuclear materials. Various combinations of reactor type and fuel composition were analyzed using Principal Components Analysis (PCA) and Partial Least Squares Discriminant Analysis (PLSDA) of the concentrations of nine U and Pu isotopes in fuel as a function of burnup. Real-world variation in the concentrations of (234)U and (236)U in the fresh (unirradiated) fuel was incorporated. The U and Pu were also analyzed separately, with results that suggest that, even after reprocessing or environmental fractionation, Pu isotopes can be used to determine both the source reactor type and the initial fuel composition with good discrimination.  相似文献   

19.
Despite more than 20 years of economic progress, especially in emerging economies like Brazil, the gap between developed and developing countries is still large, and environment problems have risen significantly. In this context, this paper aims to make the Brazilian furniture production cleaner, analyzing the environmental requirements considered by the micro and small enterprises (SMEs) in made-to-order furniture industry during the product development process (PDP). Another attempt was to identify the internal and external factors that led to the incorporation of these requirements. In this regard, a comprehensive review of eco-design concept that consists of composing environmental requirements into the PDP, through methods, tools, guidelines and techniques, was carried out. The data were collected using semi-structured interviews and in loco observations, analyzing each activity of the PDP and the environmental requirements on 18 SMEs in Brazil. The outcomes show that the economic factors determine the way in which the enterprises respond to the environmental issues and how adequate their companies according to laws and regulations. Moreover, the small number of qualified professionals in this field lead to difficulties to structure the sector, in other words, to produce with less environment impact.  相似文献   

20.
This paper aims to present an assessment of the environmental radiological exposure at a Brazilian area of high natural radiation and discusses the indoor radon exposure risk. A survey of inhabitant exposures arising from the inhalation of radon progeny and external gamma exposure was conducted in urban and rural areas of the Po?os de Caldas Plateau, which is recognized worldwide as a high natural radiation region. The results of this survey indicated that highest radiation exposure was restricted to the rural area of Po?os de Caldas. The radiation exposure in urban locations was quite similar to the values observed in normal background areas in some Brazilian counties. By the application of a constant relative risk model, an additional 20% in the lifetime risk of lung cancer mortality due to the exposure to radon progeny was estimated at Po?os de Caldas. It was also estimated that 16% of all lung cancer deaths at Po?os de Caldas county could be attributable to radon exposure.  相似文献   

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