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51.

Purpose  

As one component of the German ecological environment observation, the Environmental Specimen Bank program was initiated in the mid-1980s. Under the program, representative specimens of marine, fresh water, and terrestrial ecosystems are sampled regularly and archived under chemically stable conditions. An initial characterization of the samples provides data regarding the status quo of the respective ecosystems. The aim of the present publication is to give insight into these real-time monitoring data, which have been generated for the last 10 to 20 years. This is done exemplarily for the heavy metals cadmium (Cd), mercury (Hg), and lead (Pb) in marine specimens of the Baltic and the North Sea.  相似文献   
52.
PM10 measurements were started in November 1992 at Melpitz site. The mean PM10 concentration in 1993 was 38 μg m?3 in the summer season (May until October) and about 44 μg m?3 in the winter season (November until April). The mean PM10 level decreased until 1999 and varies now in ranges from 20–34 μg m?3 to 17–24 μg m?3 (minimum and maximum mean values for 1999–2008) in winter and summer seasons, respectively. High volume filter samples of particles PM10, PM2.5 and PM1 were characterized for mass, water-soluble ions, organic and elemental carbon from 2004 until 2008. The percentage of PM2.5 in PM10 varies between summer (71.6%) and winter seasons (81.9%). Mean concentrations of PM10, PM2.5 and PM1 in Melpitz were 20, 15, and 13 μg m?3 in 2004, 22, 18, and 13 μg m?3 in 2005, 24, 19, and 12 μg m?3 in 2006 and 22, 17, and 12 μg m?3 in 2007, respectively. In the four winters the rural background concentration PM10 at Melpitz exceeded the daily 50 μg m?3 limit for Europe on 8, 8, 7 and 6 days, respectively.Findings for a simple two-sector-classification of the samples (May 2004 until April 2008) using 96-h backward trajectories for the identification of source regions are: Air masses were transported most of time (60%) from the western sector and secondly (17%) from the eastern sector. The lowest daily mean mass concentration PM10 were found during western inflow in summer (17 μg m?3) containing low amounts of sulphate (2.4 μg m?3), nitrate (1.7 μg m?3), ammonium (1.1 μg m?3) and TC (3.7 μg m?3). In opposite the highest mean mass concentration PM10 was found during eastern inflow in winter (35 μg m?3) with high amounts of sulphate (6.1 μg m?3), nitrate (5.4 μg m?3), ammonium (3.8 μg m?3) and TC (9.4 μg m?3). An estimation of secondary formed OC (SOA) shows 0.8–0.9 μg m?3 for air masses from West and 2.1–2.2 μg m?3 from East. The seasonal difference can be neglected.The half-hourly measurements of the particle mass concentration PM10 evaluated as mean daily courses using a TEOM® show low values (14–21 μg m?3) in summer and winter for air masses transported from West and the highest concentrations (31–38 μg m?3) in winter for air masses from East.The results demonstrate the influence of meteorological parameters on long-range transport, secondary particle mass formation and re-emission which modify mass concentration and composition of PM10, PM2.5 and PM1. Melpitz site is located in the East of Germany faraway from strong local anthropogenic emissions (rural background). Therefore, this site is suitable for investigation of the influence of long-range transport of air pollution in continental air masses from the East with source regions inside and outside of the European Union.  相似文献   
53.
This paper synthesizes data on aerosol (particulate matter, PM) physical and chemical characteristics, which were obtained over the past decade in aerosol research and monitoring activities at more than 60 natural background, rural, near-city, urban, and kerbside sites across Europe. The data include simultaneously measured PM10 and/or PM2.5 mass on the one hand, and aerosol particle number concentrations or PM chemistry on the other hand. The aerosol data presented in our previous works (Van Dingenen et al., 2004, Putaud et al., 2004) were updated and merged to those collected in the framework of the EU supported European Cooperation in the field of Scientific and Technical action COST633 (Particulate matter: Properties related to health effects). A number of conclusions from our previous studies were confirmed. There is no single ratio between PM2.5 and PM10 mass concentrations valid for all sites, although fairly constant ratios ranging from 0.5 to 0.9 are observed at most individual sites. There is no general correlation between PM mass and particle number concentrations, although particle number concentrations increase with PM2.5 levels at most sites. The main constituents of both PM10 and PM2.5 are generally organic matter, sulfate and nitrate. Mineral dust can also be a major constituent of PM10 at kerbside sites and in Southern Europe. There is a clear decreasing gradient in SO42? and NO3? contribution to PM10 when moving from rural to urban to kerbside sites. In contrast, the total carbon/PM10 ratio increases from rural to kerbside sites. Some new conclusions were also drawn from this work: the ratio between ultrafine particle and total particle number concentration decreases with PM2.5 concentration at all sites but one, and significant gradients in PM chemistry are observed when moving from Northwestern, to Southern to Central Europe. Compiling an even larger number of data sets would have further increased the significance of our conclusions, but collecting all the aerosol data sets obtained also through research projects remains a tedious task.  相似文献   
54.
Organo-Sn, -Pb and -Hg compounds were monitored in gases and leachates of 11 municipal waste landfills and one hazardous waste landfill from Bavaria, Germany, with the objectives to estimate the methylation of Sn, Pb and Hg and to assess the risk of their release into the adjacent environment. In the gases, tetramethyl Sn predominated (>80% of total gaseous Sn) with concentrations up to 160mug Sn m(-3). Dimethyl-Hg and tetramethyl-Pb were only occasionally detected with concentrations up to 2.9 and 2.1mugm(-3) as Hg or Pb, respectively. In all leachates, trimethyl-Sn dominated with a maximum concentration of 2100ng Sn L(-1). No organo-Pb compounds were found, and monomethyl-Hg was detected in only one leachate. The concentrations of trimethyl-Sn were up to 100-fold higher in the condensate water than in leachates, and the concentrations of organo-Sn compounds were lower in the adjacent groundwater than in the corresponding leachates. The high abundance of methylated Sn species in the gases and leachates indicates Sn methylation, suggesting the landfill as a source for organo-Sn compounds. In comparison, methylation of Hg and Pb was of little importance, probably due to low Hg concentrations and low rates of Pb methylation in the landfill. The risks of organo-Sn compounds release to the adjacent air is low due to flaring of landfill gases. However, there is probable release of organo-Sn compounds, especially trimethyl-Sn, to the adjacent groundwater.  相似文献   
55.
In this study the fate of pharmaceuticals and personal care products which are irrigated on arable land with treated municipal wastewater was investigated. In Braunschweig, Germany, wastewater has been irrigated continuously for more than 45 years. In the winter time only the effluent of the sewage treatment plant (STP) of Braunschweig is used for irrigation, while during summer digested sludge is mixed with the effluent. In the present case study six wells and four lysimeters located in one of the irrigated agricultural fields were monitored with regard to the occurrence of 52 pharmaceuticals and two personal care products (PPCPs; e.g. betablockers, antibiotics, antiphlogistics, carbamazepine, musk fragrances, iodinated contrast media (ICM) and estrogens). No differences in PPCP pollution of the groundwater were found due to irrigation of STP effluents with and without addition of digested sludge, because many polar compounds do not sorb to sludge and lipophilic compounds are not mobile in the soil-aquifer. Most of the selected PPCPs were never detected in any of the lysimeter or groundwater samples, although they were present in the treated wastewater irrigated onto the fields. In the groundwater and lysimeter samples primarily the ICM diatrizoate and iopamidol, the antiepileptic carbamazepine and the antibiotic sulfamethoxazole were detected up to several mugl(-1), while the acidic pharmaceuticals, musk fragrances, estrogens and betablockers were likely sorbed or transformed while passing the top soil layer. Potential estrogenic effects are likely to disappear after irrigation, since the most potent steroid estrogens were not measurable.  相似文献   
56.
In archived samples from the German environmental specimen bank (ESB) organotin compounds including tributyltin (TBT) and triphenyltin (TPT) as well as their potential degradation products were quantified. Muscles of bream (Abramis brama) sampled in the period 1993-2003 from the rivers Rhine, Elbe, Saale, Mulde, Saar, and from Lake Belau (period 1988-2003) were analyzed by gas chromatography/atomic emission detection-coupling after extraction and derivatization. TBT was detected in nearly all samples and a decrease in levels was observed at all sampling sites. At most sites, the reduction seemed to be a result of the ban on the use of TBT-based antifoulants for the application on small boats, which became effective in Germany in 1989. Highest TBT levels were found in fish from the Elbe near Blankenese (470 ng TBT cation per g fresh weight; in 1995) and lowest in bream from Lake Belau (<1 ngg(-1); in 2001 and 2003). Highest TPT levels (253 ngg(-1) in 1993) were also found in bream caught near Blankenese where the occurrence seemed to be correlated to the former use of TPT as co-toxicant in antifoulants. At other sites TPT levels seemed to be correlated to its use as fungicide (e.g. 9 +/- 2 ngg(-1) in bream from Lake Belau in 2001).  相似文献   
57.
In municipal solid waste incineration (MSWI), bottom ash, generated at a stoker grate type incinerator, the critical elements were identified in terms of EU regulation. The stabilizing effect of moderate carbonation (pH 8.28 ± 0.03) on critical contaminants was studied through availability and diffusion leaching protocols. Data from the performed tests were evaluated with the goal of reusing MSWI bottom ash as secondary construction material. To investigate the mobilizing effect of CO2, suspended MSWI bottom ash was severely carbonated (pH 6.40 ± 0.07). The effect of CO2 and its interaction with other leaching factors, such as liquid/solid (L/S) ratio, leaching time, pH, ultrasound treatment, and leaching temperature, were examined using a reduced 26-1 experimental design. Contaminants identified as critical were Cr, Cu, Mo, Sb, Cl, and SO4 2−. Although moderate carbonation decreased the release of Cr, Cu, Mo, and Sb from compacted bottom ash, the main disadvantage remains its inability to demobilize Cl and SO4 2−. The hypothesized mobilizing effect of severe carbonation was proven. The treatment enhanced the separation of critical components (α = 0.05) (except for Cl), i.e., about fivefold for Sb and about twofold for Cr, Cu, and S. Nevertheless, the prospect is good that severe carbonation could constitute the deciding key parameter to facilitate the technical feasibility of a future washing process for MSWI bottom ash.  相似文献   
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60.
The processes of acclimation to hot-dry and to warm-humid climates were studied using two approaches: a quantitative analysis of literature data and an experimental study in the laboratory concerning the physiological parameters of heart rate, rectal temperature, sweat loss, and subjective assessment.

Analysis o f literature data: Data from 62 experiments with a total of 813 participants were pooled and recalculated. The experiments ranged from 6 to 24 days, air temperatures from 30.4 to 50.0°C, water vapor pressures from 1.5 to 6.5 kPa, and wet bulb globe temperatures (WBGT) from 27.4 to 38.6°C.

Laboratory studies: In the laboratory, 8 participants were acclimated during 15 consecutive days to a hot-dry climate and to a warm-humid climate, which were equivalent in terms of the WBGT (33.5 and 33.6°C, respectively). The participants walked four times for 25 min on a treadmill at a speed of 4 km/h. The hot-dry climate caused somewhat greater strain than the warm-humid condition. In the course of acclimation to the hot-dry climate, heart rate and rectal temperature started at higher levels, decreased slightly steeper but remained on a higher level throughout. Nevertheless, the differences between both thermal conditions were small, and both physiologic functions reached the point of acclimation almost at the same time under warm-humid and under hot-dry exposure. Sweat loss, which is not regarded as a valid predictor for acclimation, was considerably higher but increased less in the hot-dry than in the warm-humid climate.  相似文献   
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