74 research outputs found
Economic Growth and the Diffusion of Clean Technologies: Explaining Environmental Kuznets Curves
Production often causes pollution as a by-product. Once environmental degradation becomes too severe, regulation is introduced by which society forces the economy to make a transition to cleaner production processes. We model this transition as a change in general purpose technology" and investigate how it interferes with economic growth driven by quality-improvements. The model gives an explanation for the inverted U-shaped pollution-income relation found in empirical research for many pollutants (Environmental Kuznets Curve). We provide an analytical foundation for the claim that the rise and decline of pollution can be explained by policy-induced technology shifts and intrasectoral changes
Ex-situ Bioremediation of U(VI) from Contaminated Mine Water Using Acidithiobacillus ferrooxidans Strains
The ex-situ bioremoval of U(VI) from contaminated water using Acidithiobacillus ferrooxidans strain 8455 and 13538 was studied under a range of pH and uranium concentrations. The effect of pH on the growth of bacteria was evaluated across the range 1.5–4.5 pH units. The respiration rate of At. ferrooxidans at different U(VI) concentrations was quantified as a measure of the rate of metabolic activity over time using an oxygen electrode. The biosorption process was quantified using a uranyl nitrate solution, U-spiked growth media, and U-contaminated mine water. The results showed that both strains of At. ferrooxidans are able to remove U(VI) from solution at pH 2.5–4.5, exhibiting a buffering capacity at pH 3.5. The respiration rate of the micro-organism was affected at U(VI) concentration of 30 mg L−1. The kinetics of the sorption fitted a pseudo-first order equation, and depended on the concentration of U(VI). The KD obtained from the biosorption experiments indicated that strain 8455 is more efficient for the removal of U(VI). A bioreactor designed to treat a solution of 100 mg U(VI) L−1 removed at least 50% of the U(VI) in water. The study demonstrated that At. ferrooxidans can be used for the ex-situ bioremediation of U(VI) contaminated mine water
Status, sources and contamination levels of organochlorine pesticide residues in urban and agricultural areas: a preliminary review in central–southern Italian soils
Organochlorine pesticides (OCPs) are synthetic chemicals commonly used in agricultural activities to kill pests and are persistent organic pollutants (POPs). They can be detected in different environmental media, but soil is considered an important reservoir due to its retention capacity. Many different types of OCPs exist, which can have different origins and pathways in the environment. It is therefore important to study their distribution and behaviour in the environment, starting to build a picture of the potential human health risk in different contexts. This study aimed at investigating the regional distribution, possible sources and contamination levels of 24 OCP compounds in urban and rural soils from central and southern Italy. One hundred and forty-eight topsoil samples (0–20 cm top layer) from 78 urban and 70 rural areas in 11 administrative regions were collected and analysed by gas chromatography–electron capture detector (GC–ECD). Total OCP residues in soils ranged from nd (no detected) to 1043 ng/g with a mean of 29.91 ng/g and from nd to 1914 ng/g with a mean of 60.16 ng/g in urban and rural area, respectively. Endosulfan was the prevailing OCP in urban areas, followed by DDTs, Drins, Methoxychlor, HCHs, Chlordane-related compounds and HCB. In rural areas, the order of concentrations was Drins > DDTs > Methoxychlor > Endosulfans > HCHs > Chlordanes > HCB. Diagnostic ratios and robust multivariate analyses revealed that DDT in soils could be related to historical application, whilst (illegal) use of technical DDT or dicofol may still occur in some urban areas. HCH residues could be related to both historical use and recent application, whilst there was evidence that modest (yet significant) application of commercial technical HCH may still be happening in urban areas. Drins and Chlordane compounds appeared to be mostly related to historical application, whilst Endosulfan presented a complex mix of results, indicating mainly historical origin in rural areas as well as potential recent applications on urban areas. Contamination levels were quantified by Soil Quality Index (SoQI), identifying high levels in rural areas of Campania and Apulia, possibly due to the intensive nature of some agricultural practices in those regions (e.g., vineyards and olive plantations). The results from this study (which is in progress in the remaining regions of Italy) will provide an invaluable baseline for OCP distribution in Italy and a powerful argument for follow-up studies in contaminated areas. It is also hoped that similar studies will eventually constitute enough evidence to push towards an institutional response for more adequate regulation as well as a full ratification of the Stockholm Convention
Global commitment towards sustainable energy
Energy is crucial to economic and social development and improves quality of life. However, fossil fuel energy produces greenhouse gases (GHGs) and cannot be sustained for a long time. It is essential to tackle these problems by moving towards renewable and sustainable energy. Some countries, including those in the Arabian Gulf region, are still in the appraisal stage of adopting different forms of renewable energy. This paper reviews the business potential and likely GHG reductions associated with adopting renewable energy in Oman. It is revealed that 1·9 Mt of annual carbon dioxide emissions could be cut by producing 10% of the country’s electricity from renewables. The paper further discusses the global sustainable energy commitment under the UN Framework Convention on Climate Change and reviews the 2030 targets of some countries that are high producers of GHGs. It is anticipated that if all these planned targets are achieved, the total sustainable energy contribution could grow by nearly 11 000 TWh by 2030. These plans provide guidance for those countries still preparing to submit their plans to the UN
The EMF 32 study on technology and climate policy strategies for greenhouse gas reductions in the U.S. electric power sector: An overview
Effects of different styrene metabolites on cytotoxicity, sister-chromatid exchanges and cell-cycle kinetics in human whole blood lymphocytes in vitro
Ecological Risk-O-Meter: a risk assessor and manager software tool for better decision making in ecosystems
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