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11.
The trihalomethane (THM) concentrations in drinking water are greatly affected by the disinfection methods as well as the organic content of the water. The THM formation was shown to increase considerable during 24 hours. This indicates a higher concentration of THM at the consumers' tap compared to the levels in the outgoing water from the water work. The dosage ratio between chlorine and ammonium sulphate can be used to regulate the THM concentrations. Disinfection with a relatively high dosage of chlorine dramatically increase the THM level while the equal amount of chlorine dioxide produces trace concentrations of THM only. The relatively low THM concentrations in Swedish drinking water as compared to levels found in water from for example the USA may probably depend on the low chlorine dosage practiced in Sweden. 相似文献
12.
Vapor pressures of six chlorinated phenols were measured by capillary gas chromatography using a 1.0-m BP-1 bonded phase column. GC-determined vapor pressures (PGC) were correlated with known liquid-phase vapor pressures (PL) by the equation: Log PGC = 1.026 Log PL — 0.132, r2 = 0.975 (vapor pressures in pascals). This relationship was used to estimate PL for chloroguaiacols, chloroveratroles, and 4-nonylphenol from their experimental PGC. 相似文献
13.
Methods are described for the determination of 3,3′,4,4′-tetrachloroazobenzene (TCAB) and 3,3′,4,4′-tetrachloroazoxybenzene (TCAOB) in diuron and linuron formulations and in 3,4-dichloroaniline. The formulations were extracted with acetone, and after removal of solvent, the residue was partitioned between methanol-water and hexane. 3,4-Dichloroaniline products were partitioned between methanol-1M hydrochloric acid and hexane. The hexane extracts were purified by column chromatography on silica gel and analysed by gas chromatography with electron-capture detection. Detection limits for TCAB and TCAOB were around 0.1 ug/g using samples of one gram. Levels of 5.5 – 28 ug TCAB and 1.9 − < 0.05 ug TCAOB/g herbicide formulation and 2.4 – 460 ug TCAB/g TCAB/g 3,4-dichloroaniline have been found. TCAOB levels were below the detection limits in the 3,4-dichloroaniline samples. The presence of TCAB and TCAOB was confirmed by gas chromatography-mass spectrometry. 相似文献
14.
Ingemar Renberg Christian Bigler Richard Bindler Matilda Norberg Johan Rydberg Ulf Segerström 《Journal of environmental management》2009
Establishment of plans for environmental planning and management requires that a number of natural and societal factors must be taken into consideration. Insights into the inherent dynamics of nature as well as the role that past human activities have played for establishing the current condition of the landscape and the natural environment in general are essential. Many natural and man-made changes occur over time scales of decades or centuries, and these are difficult to comprehend without a historical perspective. Such a perspective can be obtained using palaeoecological studies, i.e. by geochemical and biological analyses of lake sediment and peat deposits. To illustrate the long-term dynamics of nature and particularly the role of man, we present here five case studies from Sweden concerning pollution, lake acidification, lake eutrophication, biodiversity, and landscape dynamics and conservation – topics of broad interests – and discuss benefits of including a longer time perspective in environmental management. 相似文献
15.
Hans T. Karlsson Jonas Klingspor Ingemar Bjerle 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1177-1180
The reaction between hydrochloric acid and solid slaked lime was investigated by passing simulated flue gas through a fixed bed reactor. The influence of CO2 and H2O present in the flue gas was studied, as well as the influence of the reaction temperature in the range 423 to 673 K. The reaction was found to be of first order with respect to the two reactants. Expressions to account for the temperature and the CO2 and H2O concentrations were derived from the experimental data. 相似文献
16.
Kristina L. Sundqvist Mats Tysklind Ingemar Cato Anders Bignert Karin Wiberg 《Environmental science and pollution research international》2009,16(4):396-409
Background, aim, and scope The primary aim of this study was to explore the variations in PCDD/F levels and homologue profiles of Baltic surface sediments
by comprehensively analyzing polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in samples from a large number of sites, encompassing not only previously
known hotspot areas, but also sites near other potential PCDD/F sources, in pristine reference areas (in which there was no
industrial activity) and offshore sites.
Materials and methods Surface sediment samples (146 in total) were collected at various points along the Swedish coast and offshore areas. In addition,
bulk deposition was sampled, monthly, at a single site in northern Sweden during 1 year. The concentrations of tetra- through octa-substituted CDD/Fs were determined in both matrices.
Results Highly elevated concentrations of PCDD/Fs were found at many sites in coastal areas and concentrations were also slightly
elevated in some offshore areas. Homologue profiles varied substantially amongst samples from coastal sites, while those from
offshore and other pristine sediments were relatively similar. The offshore sediments showed different profiles from those
observed in the deposition samples. Sediment levels of PCDD/Fs were not generally significantly correlated to organic carbon
levels, except in some pristine areas. Comparison of data obtained in this and previous studies suggest that both their levels
and profiles are similar today to those observed 20 years ago in coastal and offshore areas. The only detected trend is that
their levels appear to have decreased slightly in the offshore area of the Bothnian Sea.
Discussion The localization of hotspot areas along the coast, the lack of consensus between PCDD/F profiles of sediments and general
background, and their weak correlations with organic carbon suggest that PCDD/Fs in the study area largely originate from
local/regional emissions. However, due to complicating factors such as sediment dynamics and land upheaval, it is not possible
to conclude whether these pollutants derive from recent emissions or from a combination of recent emissions and re-distribution
of previous inputs.
Conclusions The results show that: elevated levels of PCDD/Fs are present in both coastal and offshore areas of the Baltic Sea, the major
hotspots are close to the shore, and there are large variations in profiles, indicating that local emissions are (or have
been) the major causes of pollution.
Recommendations and perspectives In order to identify other hotspot areas and trace sources, comprehensive analysis of PCDD/Fs in surface sediments is needed
in all areas of the Baltic Sea that have not been previously investigated. The high levels of PCDD/Fs observed in surface
sediments also indicate a need to elucidate whether they are due mainly to current emissions or a combination of recent pollution
and re-distribution of historically deposited pollutants. To do so, better understanding of sediment dynamics and present-day
inputs, such as riverine inputs, industrial effluents, and leakage from contaminated soil is required. There are indications
that contaminated sediments have a regional impact on fish contamination levels. However, as yet there is no statistically
robust evidence linking contaminated sediments with elevated levels in Baltic biota. It should also be noted that the Baltic
Sea is being massively invaded by the deep-burrowing polychaete Marenzielleria ssp., whose presence in sediments has been shown to increase water concentrations of hydrophobic pollutants. In awareness
of this, it is clear that high levels in sediments cannot be ignored in risk assessments. In order to investigate the emission
trends more thoroughly, analysis of PCDD/Fs in offshore sediment cores throughout the Baltic Sea is also recommended.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Reversed phase thin layer chromatography (RPTLC) has been investigated for the estimation of octanol/water partition coefficients (P), an important parameter for the prediction of the environmental behaviour of organic chemicals. A strong correlation between P derived from the traditional octanol/water system and RPTLC has been established over five orders of magnitude. RPTLC data are likewise correlated to results obtained by high performance chromatography (HPLC). Due to the low costs, simplicity and separation power RPTLC is especially suited for the investigation and screening of mixtures of compounds before more complicated tests are involved. Results from a round robin test on the determination of partition coefficients by HPLC, RPTLC and the batch method indicate the simplicity and accuracy of the RPTLC technique. Applications of the RPTLC‐technique on technical products and industrial waste waters are described. 相似文献
18.
Acid rain has caused extensive surface water acidification in Sweden since the mid-20th century. Sulfur emissions from fossil-fuel burning and metal production were the main sources of acid deposition. In the public consciousness, acid deposition is strongly associated with the industrial period, in particular the last 50 years. However, studies of lake-water pH development and atmospheric pollution, based on analyses of lake sediment deposits, have shown the importance of a long-term perspective. Here, we present a conceptual argument, using the sediment record, that large-scale atmospheric acid deposition has impacted the environment since at least Medieval times. Sulfur sources were the pre-industrial mining and metal industries that produced silver, lead and other metals from sulfide ores. This early excess sulfur deposition in southern Sweden did not cause surface water acidification; on the contrary, it contributed to alkalization, i.e. increased pH and productivity of the lakes. Suggested mechanisms are that the excess sulfur caused enhanced cation exchange in catchment soils, and that it altered iron-phosphorus cycling in the lakes, which released phosphorus and increased lake productivity. 相似文献
19.
Mário Mil-Homens Rodney L. Stevens Ingemar Cato Fátima Abrantes 《Environmental monitoring and assessment》2014,186(10):6327-6340
Comparison between an archive dataset, collected during the 1970s (1974–1977), and samples taken during the PALEO1 cruise (2002) enabled evaluation of large-scale and long-term spatiotemporal changes in Al, Cr, Ni, Pb and Zn contents in bulk surface sediments in four areas of the Portuguese shelf. The so-called gradient method (GM) with normalisation to Al, a proxy for terrigenous clay content, was applied. The studied areas are distributed from north to south along the western margin, with the northernmost located off shore the Ave and Douro rivers, a central one located off shore the Lis River and a southern one located off shore the Mira River. One-way ANOVA and Kruskal-Wallis tests were used to identify differences among study areas and periods of sample collection. A comparison of metal contents in 2002 samples with the Portuguese classification scheme regulation for deposition of dredged materials in coastal areas indicates good environmental quality in terms of Cr, Ni, Pb and Zn levels. Nevertheless, the GM results suggest an increase in metal loadings relative to Al from the 1970s to the 2002 samples (except for Pb). The Algarve area on the southern shelf is characterised by having high number of sites with metal level on class 2. These high values have traditionally been explained by a substantial supply of natural metals from the Guadiana, Tinto and Odiel rivers that drain areas Iberian Pyrite Belt formations. This supply has probably been magnified by present and past mining activities. For quality evaluation of marine sediments, especially when using total metal contents, this study shows the importance of considering all possible sources of metal loading. The natural grain size and composition variability have also a crucial influence on the metal content, and the combined evaluation allows a more holistic perspective. 相似文献
20.
Gustav Richnau Per Angelstam Sviataslau Valasiuk Lyudmyla Zahvoyska Robert Axelsson Marine Elbakidze Joshua Farley Ingemar Jönsson Ihor Soloviy 《Ambio》2013,42(2):188-200
Forest landscapes provide benefits from a wide range of goods, function and intangible values. But what are different forest owner categories’ profiles of economic use and non-use values? This study focuses on the complex forest ownership pattern of the River Helge å catchment including the Kristianstad Vattenrike Biosphere Reserve in southern Sweden. We made 89 telephone interviews with informants representing the four main forest owner categories. Our mapping included consumptive and non-consumptive direct use values, indirect use values, and non-use values such as natural and cultural heritage. While the value profiles of non-industrial forest land owners and municipalities included all value categories, the forest companies focused on wood production, and the Swedish Environmental Protection Agency on nature protection. We discuss the challenges of communicating different forest owners’ economic value profiles among stakeholders, the need for a broader suite of forest management systems, and fora for collaborative planning.