Regional aspects and statistical characterisation of the load with semivolatile organic compounds at remote Austrian forest sites

Spruce needles and humus layer of 25 remote forest sites spread all over Austria were investigated for their concentrations of PCDD/F, PCB, HCH, HCB, PCP, DDX and PAH. Influences of the sites' location on the detected concentrations have been identified: The north of Austria was characterised by a comparably higher overall pollutant load. In addition, altitudinal aspects were addressed. Between several compounds significant positive correlations have been identified, which were more pronounced for compounds with a stronger causal relationship. Pattern analyses allowed to identify--even for the remote sites--differences between the relative PCDD/F, HCH, DDX and PAH patterns of the sites. Partly, these different patterns were related to significantly higher or lower corresponding absolute concentrations of the sites.     

成都市夏季大气挥发性有机物污染及其对二次有机气溶胶生成的贡献

于2014年7月8日至8月13日在成都市城区和工业区选取两个点位开展挥发性有机物(VOCs)样品采集工作,分析结果显示,成都市夏季城区大气中VOCs质量浓度在34.1~458.8μg/m3,平均值为(137.3±91.8)μg/m3;工业区大气中VOCs质量浓度在26.7~474.9μg/m3,平均值为(135.9±103.5)μg/m3。早高峰时段(7:00~10:00)两个点位VOCs的浓度水平均高于其他时段,说明VOCs浓度受机动车排放的影响较为明显。用·OH消耗速率和臭氧生成潜势评估VOCs大气化学反应活性,结果显示,芳香烃和烯烃是影响大气化学反应活性的关键组分。城区和工业区的二次有机气溶胶(SOA)的生成潜势分别为4.859、4.559μg/m3,芳香烃不仅是臭氧生成潜势的关键活性组分,同时也是SOA的重要前体物。     

The contribution of selected organic substrates to the anaerobic cometabolism of sulfamethazine

Biodegradation of organic micropollutants is likely to occur due to cometabolism by particular microbial groups. In an effort to identify the stages of anaerobic digestion potentially involved in the biodegradation of the veterinary antimicrobial sulfamethazine (SMZ), the influence of selected carbon sources (sucrose, glucose, fructose, ethanol, meat extract, cellulose, soluble starch, soy oil, acetic acid, propionic acid and butyric acid) on SMZ removal by anaerobic sludge was evaluated in short-term batch experiments. Adsorption to the granular sludge constituted a significant removal mechanism, accounting for 39% of SMZ removal in control experiments. The presence of glucose, fructose, sucrose and meat extract exerted an inducing effect on SMZ degradation, resulting in removal efficiencies of 54, 53, 58 and 61%, respectively, indicating the occurrence of cometabolism. Time courses of sucrose and meat extract degradation revealed markedly distinct organic acid profiles but resulted in similar SMZ removals. Temporal profiles of acetic and propionic acid degradation were not associated with SMZ removal, as changes in SMZ concentration were observed even after the organic acids had been completely removed. The experimental results suggest that SMZ cometabolism is not associated to sucrose hydrolysis, acetoclastic methanogenesis and acetogenesis from propionic acid.     

The contribution of azo dyes to the mutagenic activity of the Cristais River

To verify whether dyes emitted within the discharge of a dye processing plant were contributing to the mutagenicity repeatedly found in the Cristais River, Sao Paulo, Brazil, we chemically characterized the following mutagenic samples: the treated industrial effluent, raw and treated water, and the sludge produced by a Drinking Water Treatment Plant (DWTP) located approximately 6 km from the industrial discharge. Considering that 20% of the dyes used for coloring activities might be lost to wastewaters and knowing that several dyes have mutagenic activity, we decided to analyze the samples for the presence of dyes. Thin layer chromatographic analysis indicated the presence of three prevalent dyes in all samples, except for the drinking water. This combination of dyes corresponded to a commercial product used by the industry, and it tested positive in the Salmonella assay. The structures of the dye components were determined using proton magnetic resonance and mass spectrometric (MS) methods, and the dyes were tested for mutagenicity. The blue component was identified as the C.I. Disperse Blue 373, the violet as C.I. Disperse Violet 93, and the orange as C.I. Disperse Orange 37. The dyes showed mutagenic responses of 6300, 4600, and 280 revertants/microg for YG1041 with S9 respectively. A bioassay-directed fractionation/chemical analysis showed that the C.I. Disperse Blue 373 contributed 55% of the mutagenic activity of the DWTP sludge. We showed that these dyes contributed to the mutagenic activity found in the Cristais River environmental samples analyzed and are indirectly affecting the quality of the related drinking water. Therefore, we believe that this type of discharge should be more thoroughly characterized chemically and toxicologically. Additionally, human and ecological risks associated with the release of dye processing plant effluents should be more fully investigated, especially where the resultant water is taken for human consumption.     

A tool for estimating the contribution of water-soluble organic compounds to the particle mass and condensational growth in the atmosphere

In this theoretical investigation, we elucidated several factors governing the ability of organic, water-soluble vapours to participate into either the secondary organic aerosol formation or particle condensational growth in the atmosphere. The corresponding requirements for physico-chemical properties of the vapour were estimated. These estimates were also compared with the properties of several difunctional carboxylic acids identified in the atmosphere. Our analysis indicates that while many of the considered compounds are expected to contribute to the total particle mass in the atmosphere, their role in particle condensational growth process remains uncertain. This uncertainty emerges from the fact that the saturation ratio of an organic vapour does not alone determine its ability to act as a “nonvolatile” compound. Instead, the hygroscopic and chemical properties of the vapour, as well as the particle pH and size, have also to be taken into account.     

The contribution of the anthropogenic impact of biomass utilization on ecological degradation: revisiting the G7 economies

Environmental Science and Pollution Research - The debate on ecological matters that relate to the biomass emissions nexus has gained prominence and different scholars have suggested various forms...     

Polychlorinated organic compounds (PCOCs) in waters, suspended solids and sediments of the Yangtse River

The contamination levels of polychlorinated organic compounds (PCOCs) in waters, suspended solids and sediments of the Yangtse River (Nanjing part) were analyzed in this paper. Their concentrations determined by GC/MS were very low in comparison with those in European River. The average concentration of total HCH (alpha-HCH, beta-HCH, gamma-HCH) was much higher than that of other PCOCs in all waters, which made up 65% of total amount of PCOCs. Due to the complete dilution and mixture of pollutants in the mighty Yangtse River, the content of PCOCs at each sampling station demonstrated very similar spatial pattern for waters and suspended solids. Since the small suspended solid (<0.7 microm) passed through the filter was also considered as dissolved part, the dominant parts of HCHs, PCA and PCBs were found in dissolved phase with percentage proportion of 85-94%, 72-85% and 61-78%, respectively. For DDTs, HCB and PeCB, their contents in dissolved phase were slightly higher than in particulate phase. The contents of PCOCs in sediments were also very low and varied with high fluctuation at different sampling points, indicating the heterogeneous deposition. HCB and its metabolite (PeCB) presented the highest contamination levels among PCOCs in sediments.     

Trace analysis of dissolved polychlorinated organic compounds in the water of the Yangtse River (Nanjing, China)

Eighteen organochlorine contaminants from the water samples of the Yangtse River have been qualitatively and quantitatively analyzed. The analysis of polychlorinated organic compounds (PCOCs) extracted by C18 Solid Phase Extract (SPE) was performed using HP6890 gas chromatograph coupled by ECD detector. The analytical results demonstrate that the analytical methods are reliable based on the fact that most of the recoveries for the targeted compounds are 60-90%. Most of the concerned contaminants, i.e. chlorinated pesticides and PCBs were found in the water samples of the Yangtse River, but their concentration was very low, <2.97 ng l(-1), which is far less than 1 microg l(-1)--the standard of drinking water of China. It is apparent that the PCOCs were in high concentration during the dry season, and in low concentration during the rainy season. The situation of PCOCs contamination in the water of the Yangtse River in 1999 was greatly improved in comparison with 10 years ago.     

Recent sedimentary history of anthropogenic impacts on the Culiacan River Estuary,northwestern Mexico: geochemical evidence from organic matter and nutrients

210Pb geochronology and sediment profiles of carbon, phosphorus and nitrogen were used to study time dependent changes in nutrients fluxes to Culiacan River Estuary. Results indicate that the release of urban sewage and agriculture wastes transported through Culiacan River has produced historically increased carbon, phosphorus and nitrogen fluxes to the study area. C:N:P elemental ratios showed that increments in the nutrients input begins simultaneously for C, N and P in 1948 with the clearing of the catchment for agriculture; although excess of nutrients input increased most importantly around the 1970s to roughly follow the rapidly growing population of Culiacan City. C/N ratios, delta13C and delta15N suggested that nutrient enrichment is mostly influenced by sewage delivered through Culiacan River.     

Identification and quantitation of dinaphthylsulfones in particulate matter of the Elbe river,Germany. Part VI of organic compounds as contaminants of the Elbe river and its tributaries

Gas chromatographic-mass spectrometric (GC/MS) analysis of particulate matter of the Elbe river and its tributaries Havel, Spree and Mulde revealed a group of three dinaphthylsulfone isomers as sedimentary and suspended particulate matter (SPM) contaminants. The mass spectra of dinaphthylsulfones are characterized by the molecular ion (m/z 318), and the naphthyl fragment ion m/z 127. Losses of HSO(2) and C(10)H(7)O from the molecular ion lead to different mass spectra for each isomer. The gas phase infrared spectra exhibit isomer specific bands in the spectral region between 900 and 700 wave numbers. A synthetic mixture of dinaphthylsulfones was used for isomer identification and the assignment of the gas chromatographic retention behaviour of the dinaphthylsulfone isomers. Quantitative GC/MS analysis of dinaphthylsulfones in 44 sediment and SPM samples provided comprehensive information on the overall distribution and distinct sources of dinaphthylsulfones in the Elbe river drainage system. The results indicate emissions of these compounds over prolonged times and their environmental stability in anaerobic sediments.     

The potential contribution of urban runoff to surface sediments of the Passaic River: sources and chemical characteristics

Urban runoff has been reported as the second most frequent cause of surface water pollution in the United States. Due to the incidence of runoff in urban areas, it was of interest to estimate the impact runoff may have to recent sediment quality within the lower reaches of the Passaic River. Study objectives included i) review of recent urban runoff studies to determine the occurrence and pattern of distribution of chemicals in runoff; ii)comparison of the "fingerprints" from urban runoff studies to the contaminant distributions in surface sediments from the River; and iii) estimation of mass loadings to the surface sediments using surrogate data. The analyses showed that metals and PAH distributions in the sediments were similar to those observed in runoff from diverse locations, suggesting that urban runoff composition within the Passaic watershed is similar to other urban areas. Mass loading calculations demonstrated that urban runoff is a significant source of the metals observed in the sediments, and that PAH and DDT sediment loadings could, in some cases, be accounted for by urban runoff. Observed sediment loads for PCBs, however, were significantly higher than were estimated from urban runoff.     

Influence of sorption to dissolved humic substances on transformation reactions of hydrophobic organic compounds in water. Part II: hydrolysis reactions

The effect of dissolved humic acid (HA) on two types of hydrolysis reactions was investigated: (I) dehydrochlorination of gamma-hexachlorocyclohexane (HCH) and 1,1,2,2-tetrachloroethane (TeCA) as a reaction involving hydroxide ions (OH(-)) and (II) hydrolysis of 1-octyl acetate (OA) which is catalyzed by H(+) at the applied pH value (pH 4.5). The rate of TeCA hydrolysis was not affected by addition of 2 g l(-1) of HA at pH 10 (k' = 0.33 h(-1)) but HCH hydrolysis was significantly inhibited (k' = 4.6 x 10(-3) h(-1) without HA and 2.8 x 10(-3)h(-1) at 2 g l(-1) HA). HCH is sorbed by 51% whereas TeCA sorption is insignificant at this HA concentration. Sorbed HCH molecules are effectively protected due to electrostatic repulsion of OH(-) by the net negative charge of the HA molecules. In contrast, OA hydrolysis at pH 4.5 (k' = 1.6 x 10(-5) h(-1)) was drastically accelerated after addition of 2 g l(-1) HA (k' = 1.1 x 10(-3) h(-1)). The ratio of the pseudo-first-order rate constants of the sorbed and the freely dissolved ester fraction is about 70. H(+) accumulation in the microenvironment of the negatively charged HA molecules was suggested to contribute to the higher reaction rate for the sorbed fraction in case of this H(+)-catalyzed reaction. Analogous effects from anionic surfactants are known as micellar catalysis.     

The contribution of ammonia emissions from agriculture to the deposition of acidifying and eutrophying compounds onto forests

In the vicinity of a large ammonia emission area, dry and wet deposition of acidifying and eutrophying compounds onto Douglas Fir forests was studied by sampling throughfall, stemflow and bulk precipitation. Deposition amounts of NH(4)(+) and SO(4)(2-) were recognised to be among the highest of Central Europe, resulting in extremely high inputs of (potential) acid to the forest soils (13.1 kEq ha(-1) year(-1)). The contribution of NH(3) emissions from agriculture to the total acid deposition to the forests was 52%. The total nitrogen deposition amounted to 115.0 kg ha(-1) year(-1), 83% originating from NH(3) emissions and 17% from NO(x) emissions. Calculated mean dry deposition velocities of NH(3) and SO(2) were much larger than reported in the literature. A synergistic effect between NH(3) and SO(2) in the process of dry deposition is suggested and evidence for this effect is discussed. When deposition models do not take this interaction into account, they will underestimate NH(3) and SO(2) deposition amounts in areas with intensive animal husbandry.     

Gas phase precursors to anthropogenic secondary organic aerosol: Using the Master Chemical Mechanism to probe detailed observations of 1,3,5-trimethylbenzene photo-oxidation

A detailed gas-phase photochemical chamber box model, incorporating the Master Chemical Mechanism (MCMv3.1) degradation scheme for the model anthropogenic aromatic compound 1,3,5-trimethylbenzene, has been used to simulate data measured during a series of aerosol chamber experiments in order to evaluate the mechanism under a variety of VOC/NO_x conditions.The chamber model was used in the interpretation of comprehensive high (mass and time) resolution measurements of 1,3,5-trimethylbenzene and its photo-oxidation products recorded by a Chemical Ionisation Reaction Time-of-Flight Mass Spectrometer (CIR-TOF-MS). Supporting gas and aerosol measurements have also enabled us to explore the ‘missing link’ between the gas and aerosol phases. Model-measurement comparisons have been used to gain insight into the complex array of oxygenated products formed, including the peroxide bicyclic ring opening products (α,β-unsaturated-γ-dicarbonyls and furanones) and the O₂-bridged peroxide bicyclic ring-retaining products. To our knowledge this is the first time such high molecular weight species, corresponding to various peroxide bicyclic products represented in the MCMv3.1, have been observed in the gas-phase. The model was also used to give insight into which gas-phase species were participating in SOA formation, with the primary and secondary peroxide products, formed primarily under low NO_x conditions, identified as likely candidates.     

Assessment of the impact of the emission of certain organochlorine compounds on the aquatic environment: Part I: Monochlorophenols and 2,4-dichlorophenol

The consequences of contamination of the aquatic environment by chlorophenols (2-chlorophenol, 3-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol), have been evaluated by extensive review of the available scientific data. The chlorophenols generally exert moderate toxic effects to mammalian and aquatic life, although toxicity to fish upon long-term exposure may be considerable, as has been found for 2,4-dichlorophenol. Persistence is low when adapted microflora is present, capable of biodegrading these compounds, but may become moderate to high depending on the environmental conditions. This is most pronounced for 3-chlorophenol. Bioaccumulation is expected to be low. A striking feature of these chlorophenols is their strong organoleptic effect.     

An overview of the methods used in the characterisation of natural organic matter (NOM) in relation to drinking water treatment

Natural organic matter (NOM) is found in all surface, ground and soil waters. During recent decades, reports worldwide show a continuing increase in the color and NOM of the surface water, which has an adverse affect on drinking water purification. For several practical and hygienic reasons, the presence of NOM is undesirable in drinking water. Various technologies have been proposed for NOM removal with varying degrees of success. The properties and amount of NOM, however, can significantly affect the process efficiency. In order to improve and optimise these processes, the characterisation and quantification of NOM at different purification and treatment processes stages is important. It is also important to be able to understand and predict the reactivity of NOM or its fractions in different steps of the treatment. Methods used in the characterisation of NOM include resin adsorption, size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, and fluorescence spectroscopy. The amount of NOM in water has been predicted with parameters including UV-Vis, total organic carbon (TOC), and specific UV-absorbance (SUVA). Recently, methods by which NOM structures can be more precisely determined have been developed; pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), multidimensional NMR techniques, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The present review focuses on the methods used for characterisation and quantification of NOM in relation to drinking water treatment.     

Diffuse source apportionment of the Po river eutrophying load to the Adriatic sea: assessment of Lombardy contribution to Po river nutrient load apportionment by means of an integrated modelling approach

The source apportionment of the annual nutrient load carried by the Po river to the Adriatic sea has been studied.

An integrated modelling approach was applied to the Lombardy plain area, which covers about 34% of the Po river watershed area and accounts for about 50% of the point sources’ loads carried by the river. To extract all the information available from direct instream measurements, two different modelling tools were alternatively used. The source apportionment was investigated considering both dry and wet weather scenarios. In order to quantify the apportionment in dry-weather conditions, the Lombardy portion of the Po river basin was modelled by using the US-EPA QUAL2E model. Such a simulation allowed to assess a significant contribution (about 50% of the total dry-weather load) of a not rain-driven diffuse pollution component (i.e. groundwater, springs, lake emissaries). Moreover, to estimate the rain-driven surface runoff contribution to the instream total load, the Lombardy plain area was also modelled by means of the US-DA SWAT model. SWAT results indicate a runoff contribution to the Po river instream total load of about 10 000 t N yr⁻¹ and 1300 t P yr⁻¹ (i.e. approximately the 10–20% of the total annual Lombardy nutrient load). At the event scale (i.e. the single rainstorm event) the runoff contribution may rise up to 30–80% of the total instream load. Finally, the total annual nitrogen load at the Po basin closure was estimated for the period 1985–2001. Out of a total annual load of 140 000 t N yr⁻¹, Lombardy accounts for 43% (point plus diffuse sources). The rain-driven diffuse sources constitute the 20% of the overall total load, the point sources account for 40%, whereas the remaining 40% is mainly constituted by “dry-weather diffuse sources” (i.e. groundwater, springs, lake emissaries).