The source of DDT and its metabolites contamination in Turkish agricultural soils

The concentration and impact of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane (DDT) and its metabolites (DDE: 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene) on the environment was expected to decrease after its ban in the mid-1980s. Unfortunately, DDT contamination via its presence as an impurity in dicofol (2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol) has led to a new source of contamination. This is particularly true especially in cotton production in Söke Plain, Turkey, where difocol-based pesticides are being used. The aim of this research was to investigate the extent and source of DDT contamination in cotton soils. Söke Plain soil samples were collected from 0–30, 30–60, and 60–90-cm depth and analyzed by GC/MS/MS. o,p′-DDT and p, p′-DDE were detected at 16.2 % and 17.6 % of the sites in the 0–30-cm depth of soils. In the 30–60 cm, p, p′-DDT (14.9 %), o, p′-DDE (8.1 %) and p, p′-DDE (2.7 %) were found in soil samples, and p, p′-DDT was the most prevalent with 9.5 % of the sampling sites. The dominant source of DDT particularly in the 60–90-cm depth was due to historic use of DDT. The presence of p, p′-DDE, o, p′-DDE and p,p′-DDT in the topsoil was attributed to recent dicofol applications.     

The effect of EURO-0 vehicle substitution on polycyclic aromatic hydrocarbon and carbon monoxide concentrations in an urban area

From 1994 to 2003, daily air concentrations of particle-bound polycyclic aromatic hydrocarbons (PAHs) and carbon monoxide (CO) were regularly monitored at two traffic-oriented sampling sites (A and B) in urban Genoa, Italy. The data were used to estimate effects on air quality in real situations due to progressive substitution of EURO-0 vehicles, started in 1993, with less-polluting vehicles (EURO-1, EURO-2), mainly gasoline vehicles with a catalyst. PAH profile classification and diagnostic PAH ratios were used to identify 345 samples of predominantly traffic origin. At both sites, CO and PAH daily concentrations decreased exponentially with time and the apparent half-life values calculated were 6.3 and 5.5 for CO and 3.7 and 3.5 years for PAHs at sites A and B, respectively. At site A, monitored for traffic intensity, multiple regression analyses confirmed that daily PAH and CO concentrations were positively correlated with the number of non-catalytic vehicles estimated to cross this site during sampling and negatively correlated with seasonal variables (air temperature, ozone concentration, relative air humidity). The reduction in air pollution estimated for complete substitution of non-catalytic gasoline vehicles was 89% for BaP, 85% for total PAHs and 69% for CO.     

Physicochemical variations in atmospheric aerosols recorded at sea onboard the Atlantic–Mediterranean 2008 Scholar Ship cruise (Part II): Natural versus anthropogenic influences revealed by PM10 trace element geochemistry

The geochemistry of PM₁₀ filter samples collected at sea during the Scholar Ship Atlantic–Mediterranean 2008 research cruise reveals a constantly changing compositional mix of pollutants into the marine atmosphere. Source apportionment modelling using Positive Matrix Factorization identifies North African desert dust, sea spray, secondary inorganic aerosols, metalliferous carbon, and V–Ni-bearing combustion particles as the main PM₁₀ factors/sources. The least contaminated samples show an upper continental crust composition (UCC)-normalised geochemistry influenced by seawater chemistry, with marked depletions in Rb, Th and the lighter lanthanoid elements, whereas the arrival of desert dust intrusions imposes a more upper crustal signature enriched in “geological” elements such as Si, Al, Ti, Rb, Li and Sc. Superimposed on these natural background aerosol loadings are anthropogenic metal aerosols (e.g. Cu, Zn, Pb, V, and Mn) which allow identification of pollution sources such as fossil fuel combustion, biomass burning, metalliferous industries, and urban–industrial ports. A particularly sensitive tracer is La/Ce, which rises in response to contamination from coastal FCC oil refineries. The Scholar Ship database allows us to recognise seaborne pollution sourced from NW Africa, the Cape Verde and Canary islands, and European cities and industrial complexes, plumes which in extreme cases can produce a downwind deterioration in marine air quality comparable to that seen in many cities, and can persist hundreds of kilometres from land.     

Mesocosm trials of bioremediation of contaminated soil of a petroleum refinery: comparison of natural attenuation,biostimulation and bioaugmentation

Purpose  

Contamination with petroleum hydrocarbons (PHC) is a global problem with environmental implications. Physico-chemical treatments can be used for soil cleanup, but they are expensive, and can have implications for soil structure and environment. Otherwise, biological remediation treatments are cost-effective and restore soil structure. Several remediation experiments have been carried out in the lab and in the field; however, there is the challenge to achieve as good or better results in the field as in the laboratory. In the ambit of a project aiming at investigating suitable biological remediation approaches for recovering a refinery contaminated soil, we present here results obtained in bioremediation trials. The approaches biostimulation and bioaugmentation were tested, in parallel, and compared with natural attenuation. For this purpose, mesocosm experiments were carried out inside the refinery area, which constitutes a real asset of this work.     

Extractability and mobility of mercury from agricultural soils surrounding industrial and mining contaminated areas

This study focussed on a comparison of the extractability of mercury in soils with two different contamination sources (a chlor-alkali plant and mining activities) and on the evaluation of the influence of specific soil properties on the behaviour of the contaminant. The method applied here did not target the identification of individual species, but instead provided information concerning the mobility of mercury species in soil. Mercury fractions were classified as mobile, semi-mobile and non-mobile. The fractionation study revealed that in all samples mercury was mainly present in the semi-mobile phase (between 63% and 97%). The highest mercury mobility (2.7 mg kg(-1)) was found in soils from the industrial area. Mining soils exhibited higher percentage of non-mobile mercury, up to 35%, due to their elevated sulfur content. Results of factor analysis indicate that the presence of mercury in the mobile phase could be related to manganese and aluminium soil contents. A positive relation between mercury in the semi-mobile fraction and the aluminium content was also observed. By contrary, organic matter and sulfur contents contributed to mercury retention in the soil matrix reducing the mobility of the metal. Despite known limitations of sequential extraction procedures, the methodology applied in this study for the fractionation of mercury in contaminated soil samples provided relevant information on mercury's relative mobility.     

The effects of elevated carbon dioxide levels on a Vibrio sp. isolated from the deep-sea

Introduction

The effect of oceanic CO₂ sequestration was examined exposing a deep-sea bacterium identified as Vibrio alginolyticus (9NA) to elevated levels of carbon dioxide and monitoring its growth at 2,750 psi (1,846 m depth).

Findings

The wild-type strain of 9NA could not grow in acidified marine broth below a pH of 5. The pH of marine broth did not drop below this level until at least 20.8 mM of CO₂ was injected into the medium. 9NA did not grow at this CO₂ concentration or higher concentrations (31.2 and 41.6 mM) for at least 72 h. Carbon dioxide at 10.4 mM also inhibited growth, but the bacterium was able to recover and grow. Exposure to CO₂ caused the cell to undergo a morphological change and form a dimple-like structure. The membrane was also damaged but with no protein leakage.     

Road traffic impact on urban atmospheric aerosol loading at Oporto,Portugal

At urban areas in south Europe atmospheric aerosol levels are frequently above legislation limits as a result of road traffic and favourable climatic conditions for photochemical formation and dust suspension. Strategies for urban particulate pollution control have to take into account specific regional characteristics and need correct information concerning the sources of the aerosol.With these objectives, the ionic and elemental composition of the fine (PM_2.5) and coarse (PM_2.5–10) aerosol was measured at two contrasting sites in the centre of the city of Oporto, roadside (R) and urban background (UB), during two campaigns, in winter and summer.Application of Spatial Variability Factors, in association with Principal Component/Multilinear Regression/Inter-site Mass Balance Analysis, to aerosol data permitted to identify and quantify 5 main groups of sources, namely direct car emissions, industry, photochemical production, dust suspension and sea salt transport. Traffic strongly influenced PM mass and composition. Direct car emissions and road dust resuspension contributed with 44–66% to the fine aerosol and with 12 to 55% to the coarse particles mass at both sites, showing typically highest loads at roadside. In fine particles secondary origin was also quite important in aerosol loading, principally during summer, with 28–48% mass contribution, at R and UB sites respectively. Sea spray has an important contribution of 18–28% to coarse aerosol mass in the studied area, with a highest relative contribution at UB site.Application of Spatial Variability/Mass Balance Analysis permitted the estimation of traffic contribution to soil dust in both size ranges, across sites and seasons, demonstrating that as much as 80% of present dust can result from road traffic resuspension.     

The impact of preventive coping on business travelers' work and private life

Frequent business travel can be a burden for travelers' work and private life. We tested whether preventive coping (the proactive accumulation of resources in advance of potential stressors) makes such trips beneficial despite their potential to be stressful. In a longitudinal three‐wave study, we investigated whether frequent travel relates to an increase or decrease in work–life balance, emotional exhaustion, work engagement, and relationship satisfaction depending on preventive coping. Findings from a sample of 133 frequent business travelers revealed significant indirect effects for emotional exhaustion, work engagement, and relationship satisfaction through work–life balance. Among employees who engaged less in preventive coping, a higher number of business trips was related to a decrease in work–life balance, which, in turn, was related to more emotional exhaustion, less work engagement, and lower relationship satisfaction. Among those who reported higher preventive coping, we found opposing indirect effects: Frequent travel was related to an increase in work–life balance and, in turn, to less emotional exhaustion, more work engagement, and higher relationship satisfaction. These findings advance our knowledge in the field of business travel, future‐oriented coping, and work–life balance. They highlight that travelers and their organizations should resort to preventive coping to make frequent travel more beneficial.     

Studies on atmospheric degradation of diazinon in the EUPHORE simulation chamber

The gas phase atmospheric degradation of diazinon has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. The rate constant for reaction of diazinon with OH radicals was measured using a conventional relative rate method with di-n-buthylether as reference compound being k = (3.5 ± 1.2) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at 302 ± 10 K and atmospheric pressure. The available evidence indicates that tropospheric degradation of diazinon is mainly controlled by reaction with OH radicals, and that the tropospheric lifetime with respect to the OH reaction is estimated to be around 4 h whereas its lifetime with respect to the photolysis is higher than 1 d under our conditions. Significant aerosol formation was observed following the reaction of diazinon with OH radicals, and the main carbon-containing products detected in the particle phase were hydroxydiazinon, hydroxydiazoxon and 2-isopropyl-6-methyl-pyrimidinyl-4-ol.