Two years of oil disaster in the Arabian Gulf

In January–February 1991, about 1 million m³ of crude oil were released into the Arabian Gulf as a means of ecological warfare. A stretch of 644 km along the Saudi Arabian coast was heavily polluted over a width between a few meters and more than one kilometer. In four studies performed between March 1991 and April 1993 the state of representative areas of the affected coast was examined with the result that only minor changes were found in those oiled zones which are seldom inundated by the tides. Technical measures up to 1993 did not exceed the test level. A biological regeneration process is in progress which was not recognized as such in analyses of previous coastal oil pollution. Cyanobacterial mats, containing hydrocarbon-degrading bacteria, grow on oiled sediments which are regularly reached by tidal water. Shrinking and fracturing of the stable tar crusts starts a process of loosening and degrading of aged hydrocarbons.     

Haloacetic acids,phytotoxic secondary air pollutants

Haloacetic acids are atmospheric oxidation products of airborne C₂-halocarbons which are important solvents and propellants. Levels of trichloroacetate (TCA) in conifer needles from mountain ranges in Germany (Black Forest, Erzgebirge) and from two sites in Finland are compared; TCA is present in conifer needles at concentrations up to 0.7 μmol/kg, MCA up to 0.2 μmol/kg. At the Finnish sites, TCA-concentrations and branch degeneration symptoms of Scots pine are correlated. Monochloroacetate (MCA) has been determined in needle samples from Southern Germany in concentrations exceeding its phytotoxicity threshold towards photoautotrophic organisms. Data on atmospheric chloroacetate levels in Germany are also given; ambient air levels of chloroacetic acids range from about 2 pmol/m³ (TCA) to 390 pmol/m³ (MCA). TCA and dichloroacetic acid (DCA) arise from atmospheric oxidation of airborne C₂-chlorocarbons, while the source of MCA is not yet known; several tentative pathways are suggested.     

Emissions of 22 elements from brown-coal combustion

The emissions of 22 elements from a large ligniteburning power plant have been measured. The elements S, Na, Zn, Pb, Hg, Cd, and Bi, less well retained by electrostatic precipitation, have been used to prepare a rough estimate of potential emissions from the combustion of 1.1·10⁸ metric tons of brown coal for power production in the Federal Republic of Germany. The amounts of Zn, Pb, Hg, Cd, and Bi emitted are far from negligible. The annual sulfur discharge of 1.6·10⁶ t requires effective control.     

Spatial Targeting of Agri-Environmental Measures: Cost-Effectiveness and Distributional Consequences

Agri-environmental measures are payments to farmers to reduce environmental risks or to preserve cultivated landscapes. These measures are codified in European Union regulations. Poor spatial targeting is one of the major causes of low cost-effectiveness in agri-environmental measures. Existing studies on spatial targeting focus primarily on selected individual measures; hence, they do not allow for conclusions at the program level, where the planning and implementing of decisions on a number of different measures has to be made. In this study, we analyzed the impacts of two spatial targeting options (targeting of erosion-reducing measures on erosion vulnerable areas; targeting of grassland extensification on N-pollution vulnerable areas) on the cost-effectiveness of the single measures and the entire agri-environmental program of the federal state of Brandenburg in Germany. The methodological steps included an analysis of empirical data on land use and program participation, an expert-based environmental impact assessment and a spatial allocation procedure based on linear programming. The environmental impact assessment delivered goal-specific index values for each measures-land parcel combination expressing the suitability of the measures for contributing to four regionally relevant program objectives. The cost-effectiveness of the measures and the program were calculated by putting budgetary costs in relation to the achieved environmental index sum. The calculated cost-effectiveness of the program in 2006 was 89.6% of the simulated optimal cost-effectiveness. The spatial targeting of erosion-reducing measures on erosion vulnerable areas caused an increase in the cost-effectiveness at the measures level and almost no changes at the program level. The spatial targeting of grassland extensification on N-pollution vulnerable areas, despite also improving the cost-effectiveness of this measure, had negative effects on the cost-effectiveness of the program.     

Pilot study on road traffic emissions (PAHs,heavy metals) measured by using mosses in a tunnel experiment in Vienna,Austria

BACKGROUND, AIMS AND SCOPE: Over the last few years there has been extensive research for new indicators providing information about deposition resulting from road traffic and tunnel experiments received special attention in emission research. Mosses have been used for the estimation of atmospheric heavy metal and PAH depositions for more than three decades, although they were used only a few times for estimating ambient air pollution caused by traffic. In the current study, the suitability of using a moss species for monitoring road traffic emissions inside a tunnel was evaluated. This was a first-time ever attempt to use plants (mosses) as bioindicators in a tunnel experiment. Specifically, two relevant questions were examined: 1) Do mosses accumulate toxic substances derived from road traffic emissions under the extremely adverse conditions which can be found in a tunnel, and 2) Which substances can mainly be attributed to road traffic emissions and therefore be taken as efficient and reliable indicators for motor vehicles? METHODS: For the first time a biomonitor (the moss species Hylocomium splendens (Hedwig) B.S.G.) was used in a road tunnel experiment to analyse emissions from road traffic. Moss samples were exposed for four weeks in wooden frames (size 10 cm x 10 cm), covered by a thin plastic net with a mesh size of 1 cm x 1 cm. 17 elements, mainly heavy metals, and the 16 EPA-PAHs together with coronene were analysed by ICP-AES, AAS and GC-MSD. RESULTS: Enrichment factors, calculated by comparing post-experiment concentrations to those of a background site, were high for most PAHs, especially benzo(g,h,i)perylene (150.7), coronene (134.7), benzo(a)anthracene (125.0), indeno(1,2,3-c,d)pyrene (79.8), chrysene (78.1), pyrene (69.6) and benzo(b)-fluoranthene (67.4), and among the other elements for Sb (73.1), Mo (59.6), Cr (33.9), As (24.1), Cu (19.6), and Zn (17.1). All these substances can thus be taken as indicators for road traffic pollution. Concentrations were also significantly higher in the tunnel mosses for all investigated substances than along busy roads outside tunnels. Cluster analysis revealed groups of substances which could sensibly be attributed to various sources (abrasion processes, Diesel combustion) and enrichment in the various particle size classes. DISCUSSION: The extreme high concentrations in the analysed moss samples from inside the tunnel were due to higher concentrations in the ambient tunnel air, and the fact that already deposited chemical substances are not lost by rain, as well as efficient uptake capacities even under the extremely adverse conditions in a tunnel. In accordance with previous studies our results suggest that PAHs are better indicators for emissions from the burning process than heavy metals. CONCLUSIONS: As in open fields, mosses are suitable indicators for monitoring traffic emissions in tunnels. In addition to biomonitoring in open fields, in tunnel experiments mosses are even better indicators, because the confounding effects of other sources of pollution and the 'noise' in the accumulation process (e.g. washout through wet deposition) are minimised. The results of our study demonstrate the usefulness of mosses for surveying heavy metals and PAH emissions and deposition arising from road traffic sources, even under the extremely adverse conditions of the tunnel environment. RECOMMENDATION: It can be considered that biomonitors like mosses are a suitable alternative to technical particle filters inside tunnels. They are easy to handle, low in costs and valuable information regarding traffic emissions can be obtained. PERSPECTIVE: The results of this pilot-study proved the feasibility of the method, however, should be corroborated by further investigations based on a sample set that allows for generalization of the findings and might even include other moss species. A comparison of technical measurements with the biomonitoring method could lead to a more general acceptance of the results.     

Variability in vehicle and dummy responses in rear-end collisions

OBJECTIVE: The objective of this study was to quantify the occupant response variability due to differences in vehicle and seat design in low-speed rear-end collisions. METHODS: Occupant response variability was quantified using a BioRID dummy exposed to rear-end collisions in 20 different vehicles. Vehicles were rolled rearward into a rigid barrier at 8 km/h and the dynamic responses of the vehicle and dummy were measured with the head restraint adjusted to the up most position. In vehicles not damaged by this collision, additional tests were conducted with the head restraint down and at different impact speeds. RESULTS: Despite a coefficient of variation (COV) of less than 2% for the impact speed of the initial 8 km/h tests, the vehicle response parameters (speed change, acceleration, restitution, bumper force) had COVs of 7 to 23% and the dummy response parameters (head and T1 kinematics, neck loads, NIC, N(ij) and N(km)) had COVs of 14 to 52%. In five vehicles tested multiple times, a head restraint in the down position significantly increased the peak magnitude of many dummy kinematic and kinetic response parameters. Peak head kinematics and neck kinetics generally varied linearly with head restraint back set and height, although the neck reaction moment reversed and increased considerably if the dummy's head wrapped onto the top of the head restraint. CONCLUSIONS: The results of this study support the proposition that the vehicle, seat, and head restraint are a safety system and that the design of vehicle bumpers and seats/head restraint should be considered together to maximize the potential reduction in whiplash injuries.     

Geochemical speciation of heavy metals in semiarid soils of the central Ebro Valley (Spain)

This study describes the chemical speciation of Fe, Mn, Zn and Cr in four selected soil types representative of the more abundant agricultural soils in the central Ebro river valley in Aragón. Gypsisols, Calcisols, Solonchaks and Solonetzs represent around 20% of the total soil surface in the region. A total of 12 selected sites have been sampled and five subsamples were taken in each site to create a composite sample. The four elements have been analysed by the sequential extraction procedure of Tessier et al. [Anal. Chem. 51 (1979) 844.] by emission atomic spectrometry of solid state (ICP OES). Very little amounts of Fe and Mn were retrieved from the exchangeable phase, the ready available for biogeochemistry cycles in the ecosystems. Therefore, low quantities of Fe and Mn can be taken up by plants in these alkaline soils. Cr was not detected in the bioavailable forms as well as Zn that was only present in negligible amounts in very few samples. The absence of mobile forms of Cr in all soils eliminates the toxic risk both in the trophic chain and from its migration downwards the soil profile. The largest contents of Fe, Zn and Cr were retrieved from the residual phase where metals are strongly bound to minerals, whereas Mn from the carbonate and oxide phases amounts 80% of its total content. Gypsisols and Calcisols have the lowest metal contents while the highest are found in Solonetzs and Solonchaks.     

Untersuchungen zum ökotoxikologischen Schädigungspotenzial und Erosionsrisiko von kontaminierten Sedimenten in staugeregelten Flüssen

Particle-bound pollutants accumulate in river-bottom sediments, a process which results in a significant decrease in the ecotoxicological availability of toxicants for the majority of aquatic organisms. Under normal hydrologic conditions, the release of contaminants from bottom sediments is usually of minor importance. In contrast, flood events may remobilize highly contaminated sediments via in-stream erosion. The objective of this study was to develop a combined ecotoxicological and hydraulic approach to elucidate the ecotoxicological implications associated with the risk of erosion of contaminated sediments. This integrated strategy was applied to the lock-regulated Neckar river in Southern Germany. Both the bottom-sediment cores and suspended matter from two intensive flood events were investigated. Sediment samples below an erosional unconformity showed a sharp increase in the ecotoxicological load. Moreover, it was found that major flood events (HQ₅ and higher) could possibly erode even very old, well-consolidated and highlycontaminated sediments. The suspended matter of the high discharge events investigated (return periods of 15 to 20 years) exerted significantly higher cytotoxicity and mutagenicity than a moderate flood with a 1-year return period. These findings support the conclusion that the observed ecotoxicological effects during major floods may at least in part be due to the in-stream erosion of highly contaminated bottom sediments.