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31.
The quantitative assessment of health impacts has been identified as a crucial feature for realising the full potential of health impact assessment (HIA). In settings where demographic and health data are notoriously scarce, but there is a broad range of ascertainable ecological, environmental, epidemiological and socioeconomic information, a diverse toolkit of data collection strategies becomes relevant for the mainly small-area impacts of interest. We present a modular, cross-sectional baseline health survey study design, which has been developed for HIA of industrial development projects in the humid tropics. The modular nature of our toolkit allows our methodology to be readily adapted to the prevailing eco-epidemiological characteristics of a given project setting. Central to our design is a broad set of key performance indicators, covering a multiplicity of health outcomes and determinants at different levels and scales. We present experience and key findings from our modular baseline health survey methodology employed in 14 selected sentinel sites within an iron ore mining project in the Republic of Guinea. We argue that our methodology is a generic example of rapid evidence assembly in difficult-to-reach localities, where improvement of the predictive validity of the assessment and establishment of a benchmark for longitudinal monitoring of project impacts and mitigation efforts is needed.  相似文献   
32.
Alternative vehicular fuels are proposed as a strategy to reduce urban air pollution. In this paper, we analyze the emission Impacts of electric vehicles In California for two target years, 1995 and 2010. We consider a range of assumptions regarding electricity consumption of electric vehicles, emission control technologies for power plants, and the mix of primary energy sources for electricity generation. We find that, relative to continued use of gasoline-powered vehicles, the use of electric vehicles would dramatically and unequivocally reduce carbon monoxide and hydrocarbons. Under most conditions, nitrogen oxide emissions would decrease moderately. Sulfur oxide and particulate emissions would Increase or slightly decrease. Because other areas of the United States tend to use more coal in electricity generation and have less stringent emission controls on power plants, electric vehicles may have less emission reduction benefits outside California.  相似文献   
33.
ABSTRACT

Methods that measure PM25 mass, total particulate NO3 -, and elemental carbon (EC) were evaluated in seven U.S. cities from 1997 to 1999. Sampling was performed in Bakersfield, CA; Boston, MA; Chicago, IL; Dallas, TX; Philadelphia, PA; Phoenix, AZ; and Riverside, CA. Evaluating and validating methods that measure the components of fine mass are important to the effort of establishing a speciation-monitoring network. The Harvard Impactor (HI), which measures fine particle mass, showed excellent agreement (r2 = 0.99) with the PM25 Federal Reference Method (FRM) for 81 24-hr samples in Riverside and Bakersfield. The HI also showed good precision (4.8%) for 243 24-hr collocated samples over eight studies.

The Aethalometer was employed in six of the sampling locations to measure black carbon (BC). These values were compared to EC as measured from a quartz filter using thermal analysis. For the six cities combined, the two methods were highly correlated (r2 = 0.94; 187 24-hr samples); however, the BC values were approximately 24% less than the EC measurements consistently across all six cites. This compares well to results observed for EC/BC measurements observed in other semi-urban areas. Par-ticulate NO3 - was measured using the Harvard-EPA Annular Denuder System (HEADS). This was compared to the NO3 - measured from the HI Teflon (DuPont) filter to assess NO3 - artifacts. Significant NO3 - losses (approximately 50% of total NO3 -) were found in Riverside, Philadelphia, and Boston, while minimal artifacts were observed in the other sites. Two types of HEADS configurations were employed in five cities. One system used a Na2CO3-coated glass fiber filter, and the other type used a nylon filter to collect volatilized NO3 - from the Teflon filter. The HEADS with the Na2CO3-coated filter consistently underestimated the total particulate NO3 - by approximately 20% compared to the nylon HEADS.  相似文献   
34.
Black carbon (BC), an important component of the atmospheric aerosol, has climatic, environmental, and human health significance. In this study, BC was continuously measured using a two-wavelength aethalometer (370 nm and 880 nm) in Rochester, New York, from January 2007 to December 2010. The monitoring site is adjacent to two major urban highways (I-490 and I-590), where 14% to 21% of the total traffic was heavy-duty diesel vehicles. The annual average BC concentrations were 0.76 μg/m3, 0.67 μg/m3, 0.60 μg/m3, and 0.52 μg/m3 in 2007, 2008, 2009, and 2010, respectively. Positive matrix factorization (PMF) modeling was performed using PM2.5 elements, sulfate, nitrate, ammonia, elemental carbon (EC), and organic carbon (OC) data from the U.S. Environmental Protection Agency (EPA) speciation network and Delta-C (UVBC370nm – BC880nm) data. Delta-C has been previously shown to be a tracer of wood combustion factor. It was used as an input variable in source apportionment models for the first time in this study and was found to play an important role in separating traffic (especially diesel) emissions from wood combustion emissions. The result showed the annual average PM2.5 concentrations apportioned to diesel emissions in 2007, 2008, 2009, and 2010 were 1.34 μg/m3, 1.25 μg/m3, 1.13 μg/m3, and 0.97 μg/m3, respectively. The BC conditional probability function (CPF) plots show a large contribution from the highway diesel traffic to elevated BC concentrations. The measurements and modeling results suggest an impact of the U.S Environmental Protection Agency (EPA) 2007 Heavy-Duty Highway Rule on the decrease of BC and PM2.5 concentrations during the study period.

Implications: This study suggests that there was an observable impact of the U.S EPA 2007 Heavy-Duty Highway Rule on the ambient black carbon concentrations in Rochester, New York. Aethalometer Delta-C was used as an input variable in source apportionment models and it allowed the separation of traffic (especially diesel) emissions from wood combustion emissions.  相似文献   
35.
This work presents a short review of adsorptive materials proposed and tested for removing phthalates from an aqueous environment. The objective is not to present an exhaustive review of all the types of adsorbents used, but to focus on selected types of "innovative" materials. Examples include modified activated carbon, chitosan and its modifications, β-cyclodextrin, and specific types of biomass, such as activated sludge from a wastewater treatment plant, seaweed and microbial cultures. Data from the literature do not confirm the existence of a broad-spectral adsorbent with high sorption efficiency, low production costs and environmentally friendly manufacture. According to the coefficients of Freundlich's isotherm, the most promising adsorbent of those mentioned in this work appears to be the biomass of activated sludge, or extracellular polysaccharides extracted from it. This material benefits from steady production, is cheap and readily available. Nevertheless, before putting it in practice, the treatment and adaptation of this raw material has to be taken into consideration.  相似文献   
36.
A series of miscible-displacement experiments was conducted to examine the retention and transport behavior of oocysts in natural porous media. Three soils and a model sand were used that differed in physical and geochemical properties. Transport behavior was examined under various treatment conditions to help evaluate retention mechanisms. Significant retention of oocysts was observed for all media despite the fact that conditions were unfavorable for physicochemical interactions with respect to DLVO theory. The magnitude of retention was not influenced significantly by alterations in solution chemistry (reduction in ionic strength) or soil surface properties (removal of soil organic matter and metal oxides). On the basis of the observed results, it appears that retention by secondary energy minima or geochemical microdomains was minimal for these systems. The porous media used for the experiments exhibited large magnitudes of surface roughness, and it is suggested that this surface roughness contributed significantly to oocyst retention.  相似文献   
37.
Diclofenac, a non-steroidal anti-inflammatory drug (NSAID), has caused catastrophic vulture declines across the Indian sub-continent. Here, an indirect ELISA is used to detect and quantify diclofenac in 1251 liver samples from livestock carcasses collected across India between August 2007 and June 2008, one to two years after a ban on diclofenac manufacture and distribution for veterinary use was implemented. The ELISAs applicability was authenticated with independent data obtained using LC-ESI/MS. Of 1251 samples, 1150 (91.9%) were negative for diclofenac using both methods, and 60 (4.8%) were positive at 10-4348 and 10-4441 μg kg(-1) when analysed by ELISA and LC-ESI/MS, respectively. The residue level relationship in the 60 positive samples was highly significant (p < 0.001, r(2) = 0.644). Data suggest that this immunological assay could be used not only for cost effective sample screening, but also for residue level semi-quantification.  相似文献   
38.
39.
Electrical resistance heating (ERH) has become a common method of remediation for volatile organic compounds (VOCs) in unconsolidated soils, both above and below the water table. Recently, use of ERH has expanded to include treatment of contaminated sedimentary bedrock. This article describes the implementation issues for rock remediation and provides case studies of three sites remediated by ERH in Maryland, New Jersey, and Indiana. With proper design, remediation of bedrock can be as effectively completed as remediation of overburden materials. © 2010 Wiley Periodicals, Inc.  相似文献   
40.
Appendix     
Abstract

An atrazine‐degrading bacterial isolate (M91–3) was able to utilize simazine and cyanazine as N sources for glucose‐dependent growth. The degradation of these three 5‐triazine herbicides was also investigated in binary and ternary mixtures. The organism used atrazine and simazine indiscriminately, whereas cyanazine degradation was slow and delayed until the depletion of the two other herbicides. There was no apparent effect of other commonly used herbicides on the rate of atrazine degradation by M91–3.  相似文献   
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