Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils

Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd > Hg > Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation.     

Effects of organic matter on the distribution of uranium in soil and plant matrices

This work studied interactions of uranium with pure organic compounds, such as glutathione, and more complex mixtures, such as humic acid and aqueous plant extracts. High performance liquid chromatography with UV absorption interfaced to inductively coupled plasma mass spectrometry sequential detection was used to detect organouranium complexes in a variety of soils and plant materials, indicating that nearly 100% of the uranium extracted from certain plant tissues was bound to organic ligands. In addition, soil sorption experiments indicated that humic acid generally decreased uranium sorption to soils and promoted subsequent desorption of uranium because of uranium partitioning to the organic phase. These experiments demonstrate that organic compounds influence the mobility and chemistry of uranium in the environment.     

Examining green public procurement using content analysis: existing difficulties for procurers and useful recommendations

Green public procurement (GPP) promises great potential for improving the environmental impact of many public organizations. However, the effects this instrument will have in the near future are unclear as there is little evidence on its exact level of engagement. This study thus aims to analyze the contents of tenders in terms of green criteria by specifically focusing on the building and construction sector. A total of 164 Italian public tenders were analyzed according to a protocol of analysis based on the GPP toolkit developed by the European Commission. Starting from a content analysis used in previous studies, a complete list of green criteria was developed in order to investigate their prevalence in the sample selected, with the aim of exploring their frequency, distribution and correlation. The results revealed a limited use of green criteria, which were mainly included as technical specifications and award criteria, thus shedding light on the difficulties that procurers are experiencing in the implementation of GPP practices. Several suggestions for policy makers and managers are identified for a better and faster implementation of green public procurement tools and methods.     

On-Road Measurement of Vehicle Tailpipe Emissions Using a Portable Instrument

Abstract

A study design procedure was developed and demonstrated for the deployment of portable onboard tailpipe emissions measurement systems for selected highway vehicles fueled by gasoline and E85 (a blend of 85% ethanol and 15% gasoline). Data collection, screening, processing, and analysis protocols were developed to assure data quality and to provide insights regarding quantification of real-world intravehicle variability in hot-stabilized emissions. Onboard systems provide representative real-world emissions measurements; however, onboard field studies are challenged by the observable but uncontrollable nature of traffic flow and ambient conditions. By characterizing intravehicle variability based on repeated data collection runs with the same driver/vehicle/route combinations, this study establishes the ability to develop stable modal emissions rates for idle, acceleration, cruise, and deceleration even in the face of uncontrollable external factors. For example, a consistent finding is that average emissions during acceleration are typically 5 times greater than during idle for hydrocarbons and carbon dioxide and 10 times greater for nitric oxide and carbon monoxide. A statistical method for comparing on-road emissions of different drivers is presented. Onboard data demonstrate the importance of accounting for the episodic nature of real-world emissions to help develop appropriate traffic and air quality management strategies.     

Do environmental management systems improve environmental performance? Empirical evidence from Italian companies

This paper reports the results of a research carried out on environmental performance in companies with an environmental management system registered under the EMAS regulation. By applying an empirical approach, the article analyses the trend of the environmental performance of a sample of 64 Italian companies pertaining to 6 different industrial sectors, which have achieved EMAS registration for at least three years. The trends of the environmental indicators included in the environmental statements, officially validated by a third party and traceable to a period of time before and after the registration, were collected and evaluated. In particular, the influence of the EMAS registration on the improvement or the worsening of the environmental performance was analyzed and thus the ability of this instrument to pursue continuous improvement, a founding principle of environmental management certification schemes. Data obtained indicate that in some cases, EMAS leads to an actual improvement of environmental performance, even in the short period.     

Quantification of Variability and Uncertainty in Lawn and Garden Equipment NOx and Total Hydrocarbon Emission Factors

Abstract

Variability refers to real differences in emissions among multiple emission sources at any given time or over time for any individual emission source. Variability in emissions can be attributed to variation in fuel or feedstock composition, ambient temperature, design, maintenance, or operation. Uncertainty refers to lack of knowledge regarding the true value of emissions. Sources of uncertainty include small sample sizes, bias or imprecision in measurements, nonrepresentativeness, or lack of data. Quantitative methods for characterizing both variability and uncertainty are demonstrated and applied to case studies of emission factors for lawn and garden (L&G) equipment engines. Variability was quantified using empirical and parametric distributions. Bootstrap simulation was used to characterize confidence intervals for the fitted distributions. The 95% confidence intervals for the mean grams per brake horsepower/hour (g/hp-hr) emission factors for two-stroke engine total hydrocarbon (THC) and NO_x emissions were from -30 to +41% and from -45 to +75%, respectively. The confidence intervals for four-stroke engines were from -33 to +46% for THCs and from -27 to +35% for NO_x. These quantitative measures of uncertainty convey information regarding the quality of the emission factors and serve as a basis for calculation of uncertainty in emission inventories (Els).     

Residual Cadmium and Lead Pollution at a Former Soviet Military Airfield in Tartu, Estonia

This paper presents data on the levels and dynamics of cadmium (Cd) and lead (Pb) concentration in the plants, soil, and groundwater of the landing corridor and airfield of a former Soviet military air base in Estonia, immediately at the end of its 40-year service in 1992 and over the following 8 yr. In 1991–92 we found high Cd concentrations in the meadow plants Trifolium pratense and Dactylis glomerata (up to 56 mg kg^-1). In 1993, the Cd concentration had dropped to 0.12–0.19 mg kg^-1, and stabilized in 1997–2000 at 0.04 mg kg^-1. Cd concentration in plants decreased significantly with increasing distance from the landing strip. Elevated Cd concentration (0.012 mg L^-1) was found in the fuel of the TU-22M (Backfire) strategic bombers. In 1991 and 1993, leaded fuel influenced the mean Pb concentration in plants (1.8–4.2 mg kg^-1). Average Pb concentration in both topsoil and the 30–40 cm soil horizon decreased between 1991 and 2000 from 28 to 6.5 and from 13.5 to 4.3 mg kg^-1, respectively. Cd concentration in the topsoil of the landingcorridor showed a significant increase between 1991 and 1993 (0.07–0.3 and 0.3–1.2 mg kg^-1, respectively), but stabilized later on the level of 0.04 mg kg^-1. The concentrations of both Pb and Cd in the soil were higher closer to the fuel bunkers. Current assessment of the movement of these metals from the vegetation to the soil and to groundwater is linked to potential leaching to the surrounding environment.     

Uncertainty analysis of integrated gasification combined cycle systems based on Frame 7H versus 7F gas turbines

Integrated gasification combined cycle (IGCC) technology is a promising alternative for clean generation of power and coproduction of chemicals from coal and other feedstocks. Advanced concepts for IGCC systems that incorporate state-of-the-art gas turbine systems, however, are not commercially demonstrated. Therefore, there is uncertainty regarding the future commercial-scale performance, emissions, and cost of such technologies. The Frame 7F gas turbine represents current state-of-practice, whereas the Frame 7H is the most recently introduced advanced commercial gas turbine. The objective of this study was to evaluate the risks and potential payoffs of IGCC technology based on different gas turbine combined cycle designs. Models of entrained-flow gasifier-based IGCC systems with Frame 7F (IGCC-7F) and 7H gas turbine combined cycles (IGCC-7H) were developed in ASPEN Plus. An uncertainty analysis was conducted. Gasifier carbon conversion and project cost uncertainty are identified as the most important uncertain inputs with respect to system performance and cost. The uncertainties in the difference of the efficiencies and costs for the two systems are characterized. Despite uncertainty, the IGCC-7H system is robustly preferred to the IGCC-7F system. Advances in gas turbine design will improve the performance, emissions, and cost of IGCC systems. The implications of this study for decision-making regarding technology selection, research planning, and plant operation are discussed.     

To everything there is a season: Reinvest in Minnesota (RIM) and soil conservation

The paper explores the severity of the problem of soil erosion and a variety of approaches to the problem. The typology of approaches includes doing nothing, individual party litigation, the state's invocation of public trust doctrine, and the state's exercise of its police power. The Reinvest in Minnesota Program reflects the state's exercise of its police power and addresses the problem of soil erosion by retiring marginal land from crop production through conservation easements. Programs such as Reinvest in Minnesota also reflect a certain ethic about the land.     

Collagen biosynthesis in cell culture from chorionic villi

After chorionic villus biopsy of human placenta, cell cultures were propagated with Ham's F10 medium or Eagle's minimum essential medium (MEM). It was possible to study the morphology of the cells by transmission electron microscopy (TEM) after a special culture of the cells in a collagen gel. The cells embedded in a collagen gel were able to contract the gel and to organize collagen fibres, as fibroblast cultures do. TEM showed vacuolization and well-developed cisternae of the endoplasmic reticulum, especially in the case of MEM culture. The aim was to determine whether cells cultivated from early placenta were able to synthesize enough collagen for a metabolic study. A high level of collagen biosynthesis could be quantified. Types I and III collagen can be determined which is useful for studying the abnormalities of collagen synthesis in suspected cases of osteogenesis imperfecta or Ehlers–Danlos type IV syndrome. The hydroxylation of lysine can also be studied with respect to Ehlers–Danlos type VI syndrome. Moreover, these cells, in contrast to fibroblast cultures, made it possible to study the biosynthesis of type IV collagen.