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The release of metals and metal-containing compounds into the environment is a growing concern in developed and developing countries, as human exposure to metals is associated with adverse health effects in virtually every organ system. Unfortunately, quantifying metals in the environment is expensive, analysis costs using certified laboratories typically exceed $100/sample, making the routine analysis of toxic metals cost-prohibitive for applications such as occupational exposure or environmental protection. Here, we report on a simple, inexpensive technology with the potential to render toxic metals detection accessible for both the developing and developed world that combines colorimetric and electrochemical microfluidic paper-based analytical devices (mPAD) in a three-dimensional configuration. Unlike previous mPADs designed for measuring metals, the device reported here separates colorimetric detection on one layer from electrochemical detection on a different layer. Separate detection layers allows different chemistries to be applied to a single sample on the same device. To demonstrate the effectiveness of this approach, colorimetric detection is shown for Ni, Fe, Cu, and Cr and electrochemical detection for Pb and Cd. Detection limits as low as 0.12 μg (Cr) were achieved on the colorimetric layer while detection limits as low as 0.25 ng (Cd and Pb) were achieved on the electrochemical layer. Selectivity for the target analytes was demonstrated for common interferences. As an example of the device utility, particulate metals collected on air sampling filters were analyzed. Levels measured with the mPAD matched known values for the certified reference samples of collected particulate matter. [ABSTRACT FROM AUTHOR]

The article discusses an environmental research paper entitled "Impact of Transgenic Tobacco on Trinitrotoluene (TNT) Contaminated Soil Community." The paper shows that genetically modified plants can clean up TNT and further the remediation process for microbial communities. The method uses tobacco plants as a base.

The article focuses on the paper "Magnitude and Directional Measures of Water and Cr(VI) Fluxes by Passive Flux Meter," by Timothy J. Campbell, Kirk Hatfield, Harald Klammler, and Michael D. Annable. This paper was awarded top paper under the environmental technology category for the Best Paper Awards of the journal "Environmental Science & Technology." It attempts to measure fluctuations of contaminants of the groundwater through a more polished and low-energy passive flux meter. It also investigates the amount of gasoline that is contaminating the groundwater and how it moves with the groundwater. Furthermore, this study assesses that the differences in the masses between the adsorbed tracer and the contaminant can give a directional component to the flux.

As part of the State Implementation Plan for attaining the National Ambient Air Quality Standard for ozone, the Texas Commission of Environmental Quality has created a Highly Reactive Volatile Organic Compounds (HRVOC) Emissions Cap and Trade Program for industrial point sources in the Houston/Galveston/Brazoria area. This program has a number of unique features, including its focus on a limited group of ozone precursors and its provisions for trading emissions based on atmospheric reactivity. This series of papers examines the potential air quality impacts of this new emission trading program through photochemical modeling of potential trading scenarios; this first paper in the series describes the air quality modeling methods used to assess potential trades, the potential for localized increases in ozone concentrations (ozone ‘hot spots’) due to HRVOC emission trading, and the use of reactivity scales in the trading. When HRVOC emissions are traded on a mass basis, the simulations indicate that trading of HRVOC allowances between facilities resulted in less than 0.15 ppb (<0.13%) and 0.06 ppb (<0.06%)increases in predicted maximum, area-wide 1-h averaged and 8-h averaged ozone concentrations, respectively. Maximum decreases in ozone concentrations associated with trading, as opposed to across-the-board reductions, were larger than the increases. All of these changes are small compared to the maximum changes in ozone concentrations due to the VOC emissions from these sources (up to 5–10 ppb for 8 h averages; up to 30 ppb for 1-h averages). When emissions of HRVOCs are traded for other, less reactive emissions, on a reactivity weighted basis, air quality simulations indicate that daily maximum ozone concentrations increased by less than 0.3%. Because these relatively small changes (<1%) are for unlikely trading scenarios designed to produce a maximum change in ozone concentrations (all emissions traded into localized regions), the simulations indicate that the implementation of the trading program, as currently configured and possibly expanded, is unlikely to cause localized increases in ozone concentrations (‘hot spots’). [ABSTRACT FROM AUTHOR]

To achieve sustainability, resource consumption and waste generation must be drastically decreased. For societal acceptance, preservation of both quality of life and corporate profits are essential. One promising approach is to shift the source of value from the amount of product sold to the quality of services the product provides. This paper describes the need for redesigning recycling systems from a manufacturing perspective and then discusses the possibility of this "servicification" of products, describing our experience with prototype development We discuss development of product prototypes and their business, using consumer facsimile machines as an example of "service-oriented products". Traditional thought presumes that only products comprising new materials and components are valuable. Consideration of a service-oriented product can serve as a stimulus to revise this mode of thought and to control delivery and quality of disposed products. This paper also provides a life cycle simulation of the developed service-oriented business. Simulation results indicate that service-oriented business can potentially reduce environmental impact while extending business opportunities from the viewpoint of whole product life cycles. [ABSTRACT FROM AUTHOR]

The need to use resources efficiently and reduce environmental impacts of industrial products and processes is becoming increasingly important in engineering design; therefore, green engineering principles are gaining prominence within engineering education. This paper describes a general framework for incorporating green engineering design principles into engineering curricula, with specific examples for chemical engineering. The framework for teaching green engineering discussed in this paper mirrors the 12 Principles of Green Engineering proposed byAnastas and Zimmerman (Environ. Sci. Technol 2003, 37, 94A-101A), especially in methods for estimating the hazardous nature of chemicals, strategies for pollution prevention, and approaches leading to efficient energy and material utilization. The key elements in green engineering education, which enlarge the "box" for engineering design, are environmental literacy, environmentally conscious design, and beyond-the-plant boundary considerations. [ABSTRACT FROM AUTHOR]

What influences countries' environmental performance? Do structural differences alone affect the level of air pollution? Do economic conditions determine water quality? Might society's dominant ideology and values impact national environmental performance? Are different kinds of environmental-performance indicators affected by the same variables? This paper employs comparative empirical analyses of EPI data to address these questions. Doing so enables us to contribute the following five insights to the research literature. First, we propose a conceptual categorization of EP following their health, ecological and global aspects. Second, we demonstrate that social policy, a previously underexplored factor, affects environmental policy and performance. Third, we provide evidence for the role of international engagement in explaining global-related environmental performance. Fourth, our research extends the sample studied beyond the traditional OECD sample to 68 countries with diverse development status. Finally, we demonstrate that the multiple regression models we employed provide high levels of explanatory power (up to 89%). Collectively, the results demonstrate the important role of social policy in explaining differences in the environmental performance of countries. In addition, the differences in the influence of the explanatory variables on each of the proposed category support our theoretical arguments for differentiating between various categories of environmental performance. [ABSTRACT FROM AUTHOR]

To protect bather health at recreational beaches, fecal indicator bacterial standards are used to monitor water quality, and waters exceeding the standards are subsequently closed to bathers. However beachgoers are also in contact with beach sands, the sanitary quality of which is not included within beach monitoring programs. In fact, sands and sediments provide habitat where fecal bacterial populations may persist, and in some cases grow, in the coastal zone. Specific pathogens are less well studied in beach sands and sediments, but there is a body of evidence that they too may persist in these environments. This paper reviews the current state of knowledge regarding the abundance and distribution of fecal indicator bacteria and pathogens in beach sands of diverse climatological regions, and at beaches subjected to varied levels of anthropogenic impact In all regions fecal indicator bacteria are nearly ubiquitous in beach sands, and similar relationships emerge among fecal indicator abundance in dry sand, submerged sands, and water. Taken together, these studies contextualize a potential public health issue and identify research questions that must be addressed in order to support future policy decisions. [ABSTRACT FROM AUTHOR]

China has suffered frequent source water contamination accidents in the past decade, which has resulted in severe consequences to the water supply of millions of residents. The origins of typical cases of contamination are discussed in this paper as well as the emergency response to these accidents. In general, excessive pursuit of rapid industrialization and the unreasonable location of factories are responsible for the increasing frequency of accidental pollution events. Moreover, insufficient attention to environmental protection and rudimentary emergency response capability has exacerbated the consequences of such accidents. These environmental accidents triggered or accelerated the promulgation of stricter environmental protection policy and the shift from economic development mode to a more sustainable direction, which should be regarded as the turning point of environmental protection in China. To guarantee water security, China is trying to establish a rapid and effective emergency response framework, build up the capability of early accident detection, and develop efficient technologies to remove contaminants from water. [ABSTRACT FROM AUTHOR]

After the 1970s, Malaysia''s economy diversified from agriculture into manufacturing. The manufacturing sector''s contribution grew from a mere 13.4% of the total GDP in 1970, to 30.3% of the GDP in 2007. Realising that increasing industrialisation causes threats to the environment, Malaysia has always emphasised environmental protection. The 2008 Environmental Performance Index (EPI) study carried out by Yale University and Columbia University ranked Malaysia 26th out of 149 countries that participated in the study. However, there are still a number of challenges that need immediate attention, particularly issues pertaining to chemical management. Several initiatives pertaining to chemical management are currently carried out by various agencies across government, private sector and civil society but these initiatives take a sectoral approach. Several structures are suggested towards the establishment of a sound chemical management system (CMS) in Malaysia, namely the gazetting of a Chemical Act, the establishment of a designated Chemical Authority and the development of a Malaysian Chemical Database (MyCD). A set of economic policy instruments is also prescribed in this paper to aid the appropriate authorities in their efforts to materialize a sound chemical management system in Malaysia. [Copyright &y& Elsevier]

In a process that began in the early 1990s, the United States and other countries are moving forward to adopt the United Nations “Globally Harmonized System of Classification and Labeling of Chemicals” (GHS) that seeks to protect human health and the environment by standardizing labeling and hazard information for all chemicals sold or traded in world-wide commerce. GHS will have a significant impact on the chemical industry that manufactures and supplies chemicals and it will also have impact on the users of chemicals. Chemists and other scientists working in laboratories handle collectively thousands of chemicals in relatively small quantities in their experiments, procedures, and other laboratory operations. Recognition of chemical hazards, an essential component of laboratory safety, depends upon the availability of clear and accurate information about specific chemical hazards on labels and other sources, such as Material Safety Data Sheets (MSDSs). This paper examines the opportunities and challenges for laboratory safety resulting from implementation of GHS. Noteworthy is that the new GHS rating system is the opposite of the existing National Fire Protection Association Diamond rating system. [Copyright &y& Elsevier]

Deposition of pollutants around point sources of contamination, such as incinerators, can display complex spatial patterns depending on prevailing weather conditions,the local topography, and the characteristics of the source. Deterministic dispersion models often fail to capture the complexity observed in the field, resulting in uncertain predictions that might hamper subsequent decision-making, such as delineation of areas targeted for additional sampling or remediation. This paper describes a geostatistical simulation-based methodology that combines the detailed process-based modeling of atmospheric deposition from an incinerator with the probabilistic modeling of residual variability of field samples. The approach is used to delineate areas with high levels of dioxin TEQDF-WHO98 (toxic equivalents) around an incinerator, accounting for 53 field data and the output of the EPA Industrial Source Complex (ISC3) dispersion model. The dispersion model explains 43.7% of the variance in the soil TEQ data, whereas the regression residuals are spatially correlated with a range of 776 m. One hundred realizations of soil TEQ values are simulated on a grid with a 50 m spacing. The benefit of stochastic simulation over spatial interpolation is 2-fold: (1) maps of simulated point TEQ values can easily be aggregated to the geography that is the most relevant for decision making (e.g., census block, ZIP codes); and (2) the uncertainty at the larger scale is simply modeled by the empirical distribution of block-averaged simulated values. Incorporating the output of the atmospheric deposition model as a spatial trend yields a more realistic prediction of the spatial distribution of TEQ values than log-normal kriging using only the field data, in particular, in sparsely sampled areas away from the incinerator. The geostatistical model provided guidance for the study design (census block-based population sampling) of the University of Michigan Dioxin Exposure Study (UMDES), focused on quantifying exposure pathways to dioxins from industrial sources, relative to background exposures. [ABSTRACT FROM AUTHOR]

LCA is a quantitative method for understanding the environmental impacts of a product, yet all product purchasing decisions are ultimately subjective. Weights are the nexus between the quantitative results of LCA and the values-based, subjective choices of decision makers. In May 2007, NIST introduced a new optional weight set in Version 4.0 of the BEES software. Three key points about this new optional weight set are the basis for discussion in this paper: The new weight set was created specifically in the context of BEES. It is intended to support a practical method to assist environmentally preferable purchasing in the United States based on LCIA results. This is in contrast to the weight sets currently in BEES, which are based on generalist perspectives. The new weight set was created by a multi-stakeholder panel via the AHP method, and is a synthesis of panelists' perspectives or the relative importance of each environmental impact category in BEES. The weight set draws on each panelist's personal and professional understanding of, and value attributed to, each impact category. While the synthesized weight set may not equally satisfy each panelist's view of impact importance, it does reflect contemporary values in applying LCA to real world decisions, and represents one approach others can learn from in producing weight sets. The new weight set offers BEES users an additional option for synthesizing and comparing the environmental performance of building products and making purchasing decisions. In so doing, it strengthens the decision-making process, which is important when making product comparisons in the public domain. The Weight Set: Across all panelists and with explicit consideration of all time horizons, anthropogenic contributions to global warming, weighted at 29%, was judged most important, yet not so important that decisions can be made solely on the basis of this impact. A strong tail of other concerns include fossil fuel depletion (10%), criteria air pollutants (9%), water intake/use (8%), human health cancerous effects (8%), ecological toxicity (7%), eutrophication of water bodies (6%), land use (6%), and human health noncancerous effects (5%). Also of interest are the identified impact areas of concern assigned the lowest weights: smog formation (4%), indoor air quality (3%), acidification (3%), and ozone depletion (2%). Their low weights may indicate that there is not as much immediate concern or that the remedial actions associated with the impact for the most part are underway. [ABSTRACT FROM AUTHOR]

In many urban areas throughout the world, the rising mean and peak levels of nitrogen oxides (NOx) are a concern. Road traffic and local industry are usually the major NOx sources in urban environments, but their relative contributions to the spatial distribution of the NOx volumetric mixing ratio is normally unknown. This missing piece of information is required for designing effective abatement measures to reduce ambient NOx levels. A new method for estimating the shares of which traffic and industry contribute to the mean ambient NOx mixing ratios observed in urban environments is proposed in this paper. The estimation is based on data obtained by routine air pollution monitoring, using a few assumptions about the temporal emission patterns of NOx and SO2 in the area of study. A set of equations is formulated for the unknown industry and traffic contributions to the NOx mixing ratios at each monitoring site. These equations are solved using the gradient projection optimization method. The bootstrap technique is used to estimate the errors in the process. Spatial maps of the separate shares of industry and traffic in the total ambient NOx levels can be obtained where a sufficient aerial coverage of stations is available. An application of the method to the allocation of NOxmixing ratios to traffic and industrial sources in the Haifa Bay area, Israel, is demonstrated. The results are expected to be useful for future planning of traffic thoroughfares and industrial development in the area. [ABSTRACT FROM AUTHOR]

Fresh precipitates, deposited from seepage waters of complex-ore mine-tailing impoundment at Zlaté Hory, Czech Republic, were characterized by means of X-ray diffraction, transmission electron microscopy, low temperature and in-field Mössbauer spectroscopy, and Brunauer—Emmett—Teller surface area measurements. The prevailing phases (~96 wt %) found in precipitates are poorly crystalline, 2–6 nm sized two-line ferrihydrite, forming globular aggregates of about 150 nm in diameter, rimmed by acicular irregular nanocrystals of goethite. These nanocrystalline ferrihydrite—goethite precipitates are of a relatively high chemical purity (~3% SiO2, Zn ~ 1300 ppm, trace and rare earth elements <100 ppm) and thus applicable in various nanotechnologies. With a surface area of 270 m2 g-1, precipitate possesses a high catalytic activity in the decomposition of hydrogen peroxide, which is comparable with that found for commercially accessible FeO(OH) catalyst Another superior aspect of such natural nanoparticles presents a cheap and suitable precursor for a thermally induced solid-state synthesis of the stable core—shell α-Fe—FeO nanoparticles that are well applicable in reductive technologies of groundwater treatment. Just the possibility of using the undesirable waste contaminating the environment in further environmental technologies is the key practical benefit discussed in this paper. [ABSTRACT FROM AUTHOR]

The U.S. Army Engineer Research and Development Center Environmental Laboratory, Vicksburg, MS, conducted a study to determine the extent to which Hurricane Katrina floodwaters in the New Orleans, Louisiana area may have had impacts on wildlife habitat and other biological resources in surrounding areas. These studies were conducted as part of the Interagency Performance Evaluation Taskforce, an investigation of environmental impacts originating from the failure of the hurricane protection system during Hurricane Katrina. This paper presents data regarding the effects of pumped floodwaters on sediment chemistry, toxicity, and benthic invertebrate assemblages near pumping stations that discharged floodwaters into marshes near Chalmette and Violet, Louisiana. Chemical contamination of sediments was observed and varied among sample locations (e.g., outfall locations, wastewater treatment plant, canals, and wetlands); however, trends in the chemistry data were not always consistent with bioassay results. A comparison of the sediment chemistry data from this study with three other studies reporting concentrations of chemicals in sediments within the city of New Orleans suggested that sediments and associated contaminants present within the levees were not pumped into the marsh in appreciable quantities. [ABSTRACT FROM AUTHOR]

The amount of household hazardous waste (HHW) disposed of in the United Kingdom (UK) requires assessment. This paper describes a direct analysis study carried out in three areas in southeast England involving over 500 households. Each participating householder was provided with a special bin in which to place items corresponding to a list of HHW. The amount of waste collected was split into nine broad categories: batteries, home maintenance (DIY), vehicle upkeep, pesticides, pet care, pharmaceuticals, photographic chemicals, household cleaners, and printer cartridges. Over 1 T of waste was collected from the sample households over a 32-week period, which would correspond to an estimated 51,000 T if extrapolated to the UK population for the same period or over 7,000 T per month. Details of likely disposal routes adopted by householders were also sought, demonstrating the different pathways selected for different waste categories. Co-disposal with residual household waste dominated for waste batteries and veterinary medicines, hence avoiding classification as hazardous waste under new UK waste regulations. The information can be used to set a baseline for the management of HHW and provides information for an environmental risk assessment of the disposal of such wastes to landfill. [ABSTRACT FROM AUTHOR]

This paper presents a model structure aimed at offering an overview of the various elements of a strategy and exploring their multidimensional effects through time in an efficient way. It treats a strategy as a set of discrete events planned to achieve a certain strategic goal and develops a new form of causal networks as an interfacing component between decision makers and environment models, e.g., life cycle inventory and material flow models. The causal network receives a strategic plan as input in a discrete manner and then outputs the updated parameter sets to the subsequent environmental models. Accordingly, the potential dynamic evolution of environmental systems caused by various strategies can be stepwise simulated. It enables a way to incorporate discontinuous change in models for environmental strategy analysis, and enhances the interpretability and extendibility of a complex model by its cellular constructs. It is exemplified using an urban water management case in Kunming, a major city in Southwest China. By utilizing the presented method, the case study modeled the cross-scale interdependencies of the urban drainage system and regional water balance systems, and evaluated the effectiveness of various strategies for improving the situation of Dianchi Lake. [ABSTRACT FROM AUTHOR]

In the fall of 2002, an enhanced air monitoring site was established in Steubenville, Ohio as part of a multi-year comprehensive mercury monitoring and source apportionment study to investigate the impact of local and regional coal combustion sources on atmospheric mercury deposition in the Ohio River Valley. This study deployed advanced monitoring instrumentation, utilized innovative analytical techniques, and applied state-of-the-art statistical receptor models. This paper presents wet deposition data and source apportionment modeling results from daily event precipitation samples collected during the calendar years 2003-2004. The volume-weighted mean mercury concentrations for 2003 and 2004 were 14.0 and 13.5 ng L-1, respectively, and total annual mercury wet deposition was 13.5 and 19.7 μg m-2 respectively. Two new EPA- implemented multivariate statistical models, positive matrix factorization (PMF) and Unmix, were applied to the data set and six sources were identified. The dominant contributor to the mercury wet deposition was found by both models to be coal combustion (∼70%). Meteorological analysis also indicated that a majority of the mercury deposition found at the Steubenville site was due to local and regional sources. [ABSTRACT FROM AUTHOR]

This paper evaluates the accuracy of ozone measurements made by monitors that determine ozone concentrations in ambient air by UV absorption. These monitors are typically used to measure ozone for the purpose of establishing local compliance to air-quality standards. The study was predicated by the concern that commercially available UV absorbance 03 monitors may be subject to interference from volatile organic carbon (VOC) species that absorb light at 254 nm. To test for these and other effects, we compared simultaneous 03 measurements made by a commercial UV 03 monitor with an 03—NO chemiluminescence instrument, which is not subject to interference by VOC compounds. The comparisons were carried out in the summers of 1999 and 2000 at urban/industrial sites in Nashville and Houston, and in 2004 aboard a ship in the Gulf of Maine. In the two urban areas, we also compared the 03 measurements from these two methods with 03 measurements made by a long-path differential optical absorption spectrometer (DOAS). Our tests indicate that, with well-maintained monitors, there are no significant interferences even in areas with significant ambient concentrations of potentially interfering VOCs. [ABSTRACT FROM AUTHOR]

In a recent publication we presented experimental Leonardite humic acid/air partition coefficients for 188 polar and nonpolar organic compounds measured with one consistent method. In this paper these experimental data are evaluated with various model predictions. For the PcKocWlN model some major shortcomings become apparent. The octanol-based Karickhoff-model exhibits a good performance for the nonpolar compounds but not for the polar ones. A good description of the whole data set is achieved with a polyparameter linear free energy relationship (pp-LFER) that explicitly accounts for the nonpolar (van der Waals and cavity formation) and polar (electron donor/acceptor) interactions between the sorbate molecule and the sorbent phase. With this pp-LFER model, most of the humic acid/air partition coefficients could be predicted within a factor of 2. The pp-LFER model also successfully predicts organic-C/water partition coefficients (Kjoc) collected from the literature when it is combined with a pp-LFER for air/water partition coefficients. This supports our earlier conclusion thatthe thermodynamic cycle is applicable in the humic acid/water/air system. Based on our experimental data, we present a pp-LFER- model for humic acid/air and humic acid/water partitioning at any ambient temperatures. [ABSTRACT FROM AUTHOR]

Electrodialysis with bipolar membranes (EDBM) is a kind of technology that integrates solvent and salt dissociation. It can realize salt conversion without second salt pollution or provide H+ and 0H-/alkoxide ions in situ without salt introduction. Thus, it inherently possesses economical and environmental benefits. Moreover, its technological compatibility gives rise to new functions when it couples with other technologies, such as complexion, ion exchange, extraction, and adsorption. In view of the above peculiarities, EDBM has found many interesting applications in chemistry, food processing, biochemical industries, and environmental protection. However, its development has been restricted by such factors as lack of recognition of its contribution to industrial ecology, high membrane cost, insufficient research investment, and scarce operation experience. This paper compiles an introduction to this technology from the perspective of industrial ecology and conducts an extensive examination into EDBM applications. Its purpose is to gather synergic strength from academia, industry, and government to perfect EDBM for sustainable development. [ABSTRACT FROM AUTHOR]

In this paper, we report the large-scale synthesis of ZnO nanoplatelets as thin as 10 nm. The nanoplatelets show higher efficiency in photodegrading organic dyes than ZnO nanorods do, and for the nanoplatelets, the thinner they are, the higher the performance. The photocatalytic decomposition of organic dyes (eosin B) by ZnO nanoplatelets compares favorably to the performances of ZnS porous nanoparticles and commercial Degussa P25 titania particles. This finding may have significant implications in the environment remediation and the fabrication of functional nanodevices. [ABSTRACT FROM AUTHOR]

Although many chemicals are in use, the environmental impacts of only a few have been established, usually on per- chemical basis. Uncertainty remains about the overall impact of chemicals. This paper estimates combined toxic pressure on coastal North Sea ecosystems from 343 high-production-volume chemicals used within the catchment of rivers Rhine, Meuse, and Scheldt. Multimedia fate modeling and species sensitivity distribution-based effects estimation are applied. Calculations start from production volumes and emission rates and use physicochemical substance properties and aquatic ecotoxicity data. Parameter uncertainty is addressed by Monte Carlo simulations. Results suggest that the procedure is technically feasible. Combined toxic pressure of all 343 chemicals in coastal North Seawater is 0.025 (2.5% of the species are exposed to concentration levels above EC5O values), with a wide confidence interval of nearly 0–1. This uncertainty appears to be largely due to uncertainties in interspecies variances of aquatic toxicities and,to a lesser extent, to uncertainties in emissions and degradation rates. Due to these uncertainties, the results support gross ranking of chemicals in categories: negligible and possibly relevant contributions only. With 95% confidence, 283 of the 343 chemicals (83%) contribute negligibly (less than 0.1%) to overall toxic pressure, and only 60 (17%) need further consideration. [ABSTRACT FROM AUTHOR]

By considering risk in the early stages of a technology, costs of identifying important health and environmental impacts after a technology has widely diffused can be avoided. Nanotechnology, involving materials and objects less than 100 nm in size, is an important case in point. In this paper we analyze the research priorities discussed by various interest groups concerned with the environmental risks of nanotechnology, evaluate the distribution of federal environmental nanotechnology R&D funding, and discuss research in this field. Overall federal environmental R&D funding to date is limited and focuses more on the positive environmental applications of nanotechnology than on basic knowledge/research, tools for nanoenvironmental research, or the potential risks of nanotechnology. The situation began to change in 2004 when a significant increase occurred in federal R&D funding for the environmental implications of engineered nanomaterials. Though literature exits on the exposure, transport, and toxicity of incidental nanoparticles, little work has been published on the environmental risks of engineered nanoparticles. [ABSTRACT FROM AUTHOR]

This paper examines the ozone (O3) damages caused by nitrogen oxides (NOx) emissions in different locations around the Atlanta metropolitan area during a summer month. We calculate O3 impacts using a new integrated assessment model that links pollution emissions to their chemical transformation, transport, population exposures, and effects on human health. We find that increased NOx emissions in rural areas around Atlanta increase human exposure to ambient O3 twice as much as suburban emissions. However, increased NOx emissions in central city Atlanta actually reduce O3 exposures. For downtown emissions, the reduction in human exposures to O3 from titration by NO in the central city outweighs the effects from increased downwind O3. The results indicate that the marginal damage from NOx emissions varies greatly across a metropolitan area. The results raise concerns if cap and trade regulations cause emissions to migrate toward higher marginal damage locations. [ABSTRACT FROM AUTHOR]

The impact assessment phase of Life Cycle Assessment (LCA) has received much criticism due to lack of consistency. While the ISO standards for LCA did make great strides in advancing the consensus in this area, ISO is not prescriptive, but has left much room for innovation and therefore inconsistency. To address this lack of consistency, there is currently an effort underway to provide a conceptual framework for Life Cycle Impact Assessment (LCIA) and a recommended practice to include a list of impact categories, category indicators, and underlying methodologies. This is an enormous undertaking, especially in light of the current fundamental lack of consensus of the basic elements to be included in a LCIA (e.g., impact categories, impacts, and areas of protection). ISO 14042 requires selection of impact categories that ‘reflect a comprehensive set of environmental issues’ related to the system being studied, especially for ‘comparative assertions’ that involve public marketing claims. To be comprehensive, it is necessary to have a listing of impacts that ‘could’ be included within the LCIA before entering into discussions of impacts that ‘should’ be included. In addition to providing a critical analysis of existing and emerging impact assessment approaches, this paper will formulate a structured representation that allows more informed selection of approaches. The definitions and relationships between midpoint, endpoint, damage, and areas of protection will be presented in greater detail, along with the equations that are common to many of the approaches. Finally, a discussion of the advantages and disadvantages of displaying results at various stages in the environmental models will be presented in great detail. [ABSTRACT FROM AUTHOR]

More than 40 000 km² of former military land in the United States are contaminated with unexploded ordnance (UXO). Cleanup costs are estimated to total as much as $140 billion. The amount of contaminated acreage and total costs are likely to increase as the U.S. Department of Defense (DOD) follows through on recently announced plans to close an additional 22 domestic military bases. The U.S. Environmental Protection Agency (EPA) and DOD disagree on how these sites should be characterized to assess their risks and plan for cleanup. As a result, much potentially valuable land remains idle while remediation decisions are pending. One of the sources of disagreement is how the locations of UXO should be characterized, given that the exact spatial distribution of UXO is unknown in advance of cleanup. In this paper, we propose and test a new model to represent the spatial distribution of UXO. Unlike existing DOD models, the new model accounts for the tendency of UXO to cluster, presumably around targets at which soldiers aimed during training. We fit the cluster model to geographic data on UXO locations at two former military installations and show that it describes key characteristics of the data more accurately than the existing DOD model. We discuss how the choice of a UXO spatial distribution model could affect important decisions about cleaning up and reusing UXO-affected property. [ABSTRACT FROM AUTHOR]

Colleges and universities use labpacks to dispose of much of their chemical waste. Excessive identification of material as acute hazardous waste or including the weight of containers and packing materials may raise the regulatory status of a program leading to additional paperwork and operational restrictions. Small and conditionally exempt small quantity generators will especially benefit from careful evaluation of suspected acute hazardous waste to avoid exceeding the one kilogram per calendar month limit that invokes large quantity generator rules. In addition, the extra effort required to measure net weight of hazardous waste generated and to exclude non-regulated waste from the total may keep a campus below the monthly quantity of non-acute hazardous waste that would subject the campus to increased regulation. Carefully using the letter of the rules to measure hazardous waste quantities should not affect decisions about proper management of chemical waste to protect public health and the environment. State rules may differ from the federal rules cited in this paper. [Copyright &y& Elsevier]

Species sensitivity distributions (SSDs) are increasingly used to analyze toxicity data but have been criticized for a lack of consistency in data inputs, lack of relevance to the real environment and a lack of transparency in implementation. This paper shows how the Bayesian approach addresses concerns arising from frequentist SSD estimation. Bayesian methodologies are used to estimate SSDs and compare results obtained with time-dependent (LC50) and time-independent (predicted no observed effect concentration) endpoints for the insecticide chlorpyrifos. Uncertainty in the estimation of each SSD is obtained either in the form of a pointwise percentile confidence interval computed by bootstrap regression or an associated credible interval. We demonstrate that uncertainty in SSD estimation can be reduced by applying a Bayesian approach that incorporates expert knowledge and that use of Bayesian methodology permits estimation of an SSD that is more robust to variations in data. The results suggest that even with sparse data sets theoretical criticisms of the SSD approach can be overcome. [ABSTRACT FROM AUTHOR]

The unregulated emissions from two in-use heavy-duty transit buses fueled by compressed natural gas (CNG) and equipped with oxidation catalyst (OxiCat) control were evaluated. We tested emissions from a transit bus powered by a 2001 Cummins Westport C Gas Plus 8.3-L engine (CWest), which meets the California Air Resources Board's (CARB) 2002 optional NOx standard (2.0 g/bhp-hr). In California, this engine is certified only with an OxiCat, so our study did not include emissions testing without it. We also tested a 2000 New Flyer 40-passenger low-floor bus powered by a Detroit Diesel series 506 engine (DDCs50G) that is currently certified in California without an OxiCat. The original equipment manufacturer (OEM) offers a "low-emission" package for this bus that includes an OxiCat for transit bus applications, thus, this configuration was also tested in this study. Previously, we reported that formaldehyde and other volatile organic emissions detected in the exhaust of the DDCs50G bus equipped with an OxiCat were significantly reduced relative to the same DDCs50G bus without OxiCat. In this paper, we examine other toxic unregulated emissions of significance. The specific mutagenic activity of emission sample extracts was examined using the microsuspension assay. The total mutagenic activity of emissions (activity per mile) from the OxiCat-equipped DDC bus was generally lower than that from the DDC bus without the OxiCat. The CWest bus emission samples had mutagenic activity that was comparable to that of the OxiCat-equipped DDC bus. In general, polycyclic aromatic hydrocarbon (PAH) emissions were lower for the OxiCat-equipped buses, with greater reductions observed for the volatile and semivolatile PAH emissions. Elemental carbon (EC) was detected in the exhaust from the all three bus configurations, and we found that the total carbon (TC) composition of particulate matter (PM) emissions was primarily organic carbon (OC). The amount of carbon emissions far exceeded the PM-associated inorganic element emissions, which were detected in all exhaust samples, at comparatively small emission rates. In summary, based on these results and those referenced from our group, the use of OxiCat for the new CWest engine and as a retrofit option for the DDCs50G engine generally results in the reduction of tailpipe toxic emissions. However, the conclusions of this study do not take into account OxiCat durability, deterioration, lubricant consumption, or vehicle maintenance, and these parameters merit further study. [ABSTRACT FROM AUTHOR]

Several approaches have been developed that use ensembles of air parcel back trajectories to identify likely source regions for contaminants observed at a downwind receptor site. Although the results of these models have appeared to provide results that agree with known sources, there have not been efforts to make direct comparisons between the results of such analyses with emissions inventories. In this paper, the results of residence time analysis (RTA) of data from Underhill, VT and from Brigantine, NJ are compared to the average estimated emissions of coal- and oil-fired power plants. Excellent correspondence was found between the areas of highest probability identified in the trajectory ensemble analyses and the averaged emission intensities. [ABSTRACT FROM AUTHOR]

This paper describes a practical approach to site- dependent life-cycle analysis (SDLCA) that differentiates site-dependent environmental impacts from a system's processes by considering the geographical conditions of each process. This approach converts an environmental output into its impacts by using site-dependent characterization factors (SDCFs). This approach defines an area–the Spatial Area of iMpact Equivalency (SAME)–within the boundaries of the geographical system during site-dependent life-cycle inventory (SDLCI) analysis and calculates an environmental output from a process for the SAMEs. Each SAME represents a collection of geographical areas with internally homogeneous environmental impacts and can be mapped using a geographic information system. Preparing a SDLCI and SOCFs based on SAMEs facilitates the implementation of SDLCA by permitting the use of fewer regions during SDLCI. To demonstrate application of the SAME approach, an embodied impact intensity was formulated; it quantifies the impact directly and indirectly on the basis of the unit activity of a sector by means of input- output analysis with SDCFs. The validity of using SAMEs for SDLCA is demonstrated through two case studies: one studying suspended particulate matter, and one studying benzene. In both cases, the impact intensities are calculated using the SAME approach and the results are compared with those of site-generic LCI. [ABSTRACT FROM AUTHOR]

The assessment of human health and ecological risks at chemically contaminated sites often includes the use of models to assess chemical transport, fate, and exposure/toxicity. These models require input data on a variety of physical and chemical properties for each compound of concern. Small changes in some of these parameters may result in significant differences in estimated human health or ecological risks and in the extent of required remediation efforts. The octanol—water partition coefficient (Kow) for hydrophobic organic compounds is one such parameter, particularly because it is often used to estimate additional partitioning and bioaccumulation parameters. Unfortunately, there is considerable variability among tabulated Kow values for many compounds of concern. This paper assesses the implications of using various values of Kow to calculate health-protective polychlorinated biphenyl (PCB) sediment quality objectives(SQOs) in a case study using a simplified food chain model and the range of Kow values available from or recommended by the U. S. EPA. For the site and Kow values considered in this study, which are a snapshot of values available in the spring of 2004, the SQOs differ by as much as a factor of 5. This range of SQOs is estimated to correspond to a difference in remediation costs of $48 million. [ABSTRACT FROM AUTHOR]

Method 527 was developed to address the occurrence monitoring needs of the U.S. Environmental Protection Agency (EPA) under its second unregulated contaminant monitoring rule (UCMR 2). This method includes a wide range of semivolatile organic contaminants, including pesticides that were deferred during the first UCMR, flame retardants, and pyrethroid pesticides. This paper discusses the rationale for selection and inclusion of the various contaminants included in Method 527 and describes the challenges associated with developing analytical methods that will be used for the occurrence monitoring of such a diverse group of organic molecules, Method 527 employs solid-phase extraction with analysis by gas chromatography/mass spectrometry (GC/MS). The final method preservation scheme requires the storage of samples in amber bottles buffered at pH 3.8 using citric acid to prevent degradation from acid-catalyzed hydrolysis and from UV light. Citric acid is also an effective antimicrobial reagent, preventing this mode of loss during storage. Ethylenediaminetetraacetic acid (EDTA) is added to remove transition metals such as copper, which was determined to degrade target analytes upon storage. Finally, free available chlorine (FAC), which is present in many finished waters and found to degrade a number of the targets, is removed using ascorbic acid. The final method meets all of the EPA UCMR survey requirements for sample storage, precision, accuracy, and sensitivity and will be proposed for use under the UCMR 2. [ABSTRACT FROM AUTHOR]

Sonoprocessing is the utilization of sonic and ultrasonic waves in chemical synthesis and processes. It is a new and rapidly growing research field with broad applications in environmental engineering, green chemical synthesis, and processing. The application of this environmentally benign technique in environmental remediation is currently under active research and development Sonochemical oxidation is effective in treating toxic effluents and reducing toxicity. However, the ultrasonic treatment is highly energy intensive since sonication is relatively inefficient with respect to total input energy and is therefore not economically attractive or feasible alone. Hence, sonochemistry has not yet received much attention as an alternative for industrial and large-scale chemical and environmental processes. One of the most interesting topics in the recent advances in sonochemistry is the possibility of double or more excitations with ultrasound and other types of energy. The coupling of ultrasound with other free energy sources (i.e., UV) or chemical oxidation utilizing H2O2, O3, or ferrous ion presents interesting and attractive approaches. Therefore, many recent efforts have been devoted to improving the efficiency of sonochemical reactions by exploiting the advantages of combinative or hybrid processes involving the simultaneous or sequential use of ultrasonic irradiation and other advanced oxidation processes, electrochemical processes, and biological treatment This paper provides a critical review of the applications of ultrasound in environmental remediation, focusing on recent developments and unifying analysis of combinative or hybrid systems, namely, sonophotochemical oxidation processes. [ABSTRACT FROM AUTHOR]

Usage of the word "sustainability" is widespread and incorporates a plethora of meanings. After reviewing four extant sustainability frameworks, we propose a Sustainability Hierarchy to structure a broad array of issues that have been associated with sustainability. These issues vary widely in their urgency, severity and uncertainty of consequences, and temporal and spatial dimensions. It categorizes actions some view as unsustainable based on their direct or indirect potential to (i) endanger the survival of humans; (ii) impair human health, (iii) cause species extinction or violate human rights; or (iv) reduce quality of life or have consequences that are inconsistent with other values, beliefs, or aesthetic preferences. Effects considered include impediments to the ecosystem functions that support human life, human health, and species viability. This paper argues that for sustainability to become a more meaningful concept, the many worthy issues in the fourth category (values, beliefs, and aesthetic preferences) should not be considered sustainability concerns. Implications for companies, policy makers, and scientists are discussed. [ABSTRACT FROM AUTHOR]

Assessing the volume of soil requiring remediation and the accuracy of this assessment constitutes an essential step in polluted site management if this remediation volume is not properly assessed, misclassification may lead both to environmental risks (polluted soils may not be remediated) and financial risks (unexpected discovery of polluted soils may generate additional remediation costs). To minimize such risks, this paper proposes a geostatistical methodology based on stochastic simulations that allows the remediation volume and the uncertaintyto be assessed using investigation data. The methodology thoroughly reproduces the conditions in which the soils are classified and extracted at the remediation stage. The validity of the approach is tested by applying it on the data collected during the investigation phase of a former lead smelting works and by comparing the results with the volume that has actually been remediated. This real remediated volume was composed of all the remediation units that were classified as polluted after systematic sampling and analysis during cleanup stage. The volume estimated from the 75 samples collected during site investigation slightly overestimates (5.3% relative error) the remediated volume deduced from 212 remediation units. Furthermore, the real volume falls within the range of uncertainty predicted using the proposed methodology. [ABSTRACT FROM AUTHOR]

Organisms are able to control metal concentrations in certain tissues of their body to minimize damage of reactive forms of essential and nonessential metals and to control selective utilization of essential metals. These physiological aspects of organisms are not accounted for when assessing the risk of metals in the environment. The Critical Body Residue (CBR) approach relates toxicity to bioaccumulation and biomagnification and might at first sight provide a more accurate estimation of effects than the external concentration. When expressing CBRs on total internal concentrations, the capacity of organisms to sequester metals in forms that are not biologically reactive is neglected. The predictability of toxic effects will increase when knowledge on metal compartmentalization within the organisms' body is taken into account Insight in metal compartmentalization sheds light on the different accumulation strategies organisms can follow upon metal exposure. Using a fractionation procedure to isolate metal-rich granules and tissue fragments from intracellular and cytosolic fractions, the internal compartmentalization of metals can be approximated. In this paper, current knowledge regarding metal compartmentalization in organisms is summarized, and metal fractions are identified that are indicators of toxicity. Guidance is provided on future improvement of models, such as the Biotic Ligand Model (BLM), for risk assessment of metal stress to biota. [ABSTRACT FROM AUTHOR]

The PhATE (Pharmaceutical Assessment and Transport Evaluation) model presented in this paper was developed as a tool to estimate concentrations of active pharmaceutical ingredients (APIs) in U.S. surface waters that result from patient use (or consumption) of medicines. PhATE uses a mass balance approach to model predicted environmental concentrations (PECs) in 11 watersheds selected to be representative of most hydrologic regions of the United States. The model divides rivers into discrete segments. It estimates the mass of API that enters a segment from upstream or from publicly owned treatment works (POTW) and is subsequently lost from the segment via in-stream loss mechanisms or flow diversions (i.e., manmade withdrawals). POTW discharge loads are estimated based on the population served, the API use per capita, the potential loss of the compound associated with human use (e.g., metabolism), and the portion of the API mass removed in the POTW. Simulations using three surrogate compounds show that PECs generated by PhATE are generally within an order of magnitude of measured concentrations and that the cumulative probability distribution of PECs for all watersheds included in PhATE is consistent with the nationwide distribution of measured concentrations of the surrogate compounds. Model simulations for 11 APIs yielded four categories of results. (1) PECs fit measured data for two compounds. (2) PECs are below analytical method detection limits and thus are consistent with measured data for three compounds. (3) PECs are higher than (i.e., not consistent with) measured data for three compounds. However, this may be the consequence of as yet unidentified depletion mechanisms. (4) PECs are several orders of magnitude below some measured data but consistent with most measured data for three compounds. [ABSTRACT FROM AUTHOR]

This article presents instructions to authors, on submission of their article to the periodical "Environmental Science & Technology" (EST). EST is an authoritative source of information for professionals in a wide range of environmental disciplines. In the research section, contributed material may appear as current research papers, policy analyses, critical reviews, or correspondence. Contributions submitted to EST must be original works of the author(s) that have not been previously published or simultaneously submitted to another publication. Copyright of articles published in EST is transferred to the American Chemical Society (ACS) by the author(s). Documents accepted for publication in ACS journals will be posted on the Web as soon as publishable. -

Process simulation models and other design tools allow engineers to design, simulate, and optimize chemical processes. However, there is a critical need to incorporate green engineering into the design of these processes. This calls for extending the breadth of the design process. This paper presents an integrated framework for greener design. The framework starts the decision-making BS early as the chemical and material selection stage and also includes management and planning decisions. The design goal is not restricted to profitability, but environmental and ecological objectives are also added. However, this integration poses challenging problem of discrete and continuous decisions, nonlinear models, and uncertainties. Furthermore, there are multiple and conflicting objectives to be considered. Therefore, the core of this integrated framework is the efficient algorithmic framework for multi-objective optimization under uncertainty. Two real world case studies are presented that illustrate the promise of such a framework. [ABSTRACT FROM AUTHOR]

Millions of end-of-life electronic components are retired annually due to the proliferation of new models and their rapid obsolescence. The recovery of resources such as plastics from these goods requires their disassembly. The time required for each disassembly and its associated cost is defined by the operator's familiarity with the product design and its complexity. Since model proliferation serves to complicate an operator's learning curve, it is worthwhile to investigate the benefits to be gained in a disassembly operator's preplanning process. Effective disassembly process design demands the application of green engineering principles, such as those developed by Anastas and Zimmerman (Environ. Scl. Technol. 2003, 37, 94A-101A), which include regard for product complexity, structural commonality, separation energy, material value, and waste prevention. This paper introduces the concept of design symbols to help the operator more efficiently survey product complexity with respect to location and number of fasteners to remove a structure that is common to all electronics: the housing. With a sample of 11 different computers, printers, and monitors, we demonstrate that appropriate symbols reduce the total disassembly planning time by 13.2 mm. Such an improvement could well make efficient the separation of plastic that would otherwise be destined for waste-to-energy or landfill. The symbolic methodology presented may also improve Design for Recycling and Design for Maintenance and Support. [ABSTRACT FROM AUTHOR]

The built environment, defined by the facilities and civil infrastructure systems that people use, is the fundamental foundation upon which a society exists, develops, and survives. As the main provider and the life cycle custodian of the built environment, the Architecture, Engineering, and Construction (AEC) industry plays a critical role in determining the quality, integrity, and longevity of this foundation. In the execution of these two roles, provider and custodian, the AEC industry has had a major direct and indirect impact on the natural environment, contributing both directly and indirectly to natural resource depletion and degradation, waste generation and accumulation, and environmental impact and degradation. These impacts are not unique to the AEC industry. Other industries face similar challenges, and for many years, a wide range of constituencies within them have been attempting the implementation of the concept of sustainability within what these industries do, how they do it, and with what as a possible mechanism to slow, reduce, eliminate these impacts, and even restore conditions to a better state. In the pursuit of sustainability, the AEC industry faces challenges posed by the unique attributes and characteristics nature of facilities and civil infrastructure systems, the complexities of the current processes for their delivery and use, and the diverse set of resources required for both their delivery and their use. This paper offers a road map and an initial set of principles to implement built environment sustainability as a starting point for an ongoing, industry-wide dialogue and debate. [ABSTRACT FROM AUTHOR]

The decisions made by chemists in designing chemical products and processes directly impact the options available to engineers. The physical and chemical properties of a material, for example, dictate the type of reactor that must be used in a given process. The task of the engineer is simplified when chemists design products and processes that reduce or eliminate the use and generation of hazardous substances. Green chemistry provides a foundation on which to build green engineering. This paper highlights green chemistry technologies that minimize the need for engineering safeguards in the areas of feedstocks, reagents, solvents, and syntheses. [ABSTRACT FROM AUTHOR]

Green engineering requires the designer to consider a very extensive set of environmental impacts. To minimize these impacts, the designer must significantly expand his or her "toolset" of product design concepts, alternative materials, manufacturing systems, and analytic methods for addressing life cycle impacts. This can overwhelm a designer, who then resorts to overly simplistic rules or checklists out of necessity. The central issue is how to identify all "pollution prevention pays" opportunities and then how to deal with the unavoidable tradeoffs that arise after all these opportunities have been exhausted. This paper presents a framework for employing mathematical decision modeling toward this end. A domain-independent constrained optimization formulation is presented. A multiattribute utility function reflects the willingness to pay for environmental improvement and is the basis of the objective function. The feasibility constraints reflect the unavoidable tradeoffs. Several case studies are presented, including power systems, floor tile manufacturing, and computer systems. [ABSTRACT FROM AUTHOR]

With growing interest in recovering materials and subassemblies within consumer products at the end of their useful life, there has been an increasing interest in developing decision-making methodologies that determine how to maximize the environmental benefits of end-of- life (EOL) processing while minimizing costs under variable EOL situations. This paper describes a methodology to analyze how product designs and situational variables impact the Pareto set of optimal EOL strategies with the greatest environmental benefit for a given economic cost or profit. Since the determination of this Pareto set via enumeration of all disassembly sequences and EOL fates is prohibitively time-consuming even for relatively simple products, multi-objective genetic algorithms (GA) are utilized to rapidly approximate the Pareto set of optimal EOL trade- offs between cost and environmentally conscious actions. Such rapid calculations of the Pareto set are critical to better understand the influence of situational variables on how disassembly and recycling decisions change under different EOL scenarios(e.g., undervariable regulatory, infrastructure, or market situations). To illustrate the methodology, a case study involving the EOL treatment of a coffee maker is described. Impacts of situational variables on trade-offs between recovered energy and cost in Aachen, Germany, and in Ann Arbor, Ml, are elucidated, and a means of presenting the results in the form of a multi-situational EOL strategy graph is described. The impact of the European Union Directive regarding Waste Electric and Electronic Equipment (WEEE) on EOL trade-offs between energy recovery and cost was also considered for both locations. [ABSTRACT FROM AUTHOR]

The article focuses on two papers, which appeared within the issue of "Environmental Science and Technology," about the planet's changing climate and diminishing resources. James Mihelcic and Julie Zimmerman describe scientific and technological tools in developing countries that have proven useful in implementing sustainable living. They argue that indigenous knowledge needs to be included in global conversations on sustainability. On the second paper, Mihelcic and Zimmerman discuss such successful instruments.

The article focuses on the paper "Compound Class Specific14C Analysis of Polycyclic Aromatic Hydrocarbons Associated with PM10 and PM1.1 Aerosols from Residential Areas of Suburban Tokyo," by Hidetoshi Kumata, Eisuke Sakuma, Tatsuya Uchida, Kitao Fujiwara, and Mikio Tsuzuki. This paper was awarded with the first runner-up award under the environmental science category for the Best Paper Awards of the journal "Environmental Science & Technology." It examines the significance of combustion-derived polycyclic aromatic hydrocarbons to the creation of human cancer. Furthermore, this study recognizes the usefulness of biomass-based fuels in reducing carbon emission, however, it may also bring damage to the environment.