Background, aim, and scope Atmospheric pollution is a worldwide problem. Exposure to atmospheric pollutants causes toxic cellular effects. One of the mechanisms of toxicity by these pollutants is the promotion of oxidative stress. Several signaling pathways control cellular redox homeostasis. In this respect, nuclear factor erythroid 2-related factor 2 (Nrf2) is a crucial transcription factor in the cell's response to oxidative stress. Main features In cellular animal models, exposure to atmospheric pollutants activates Nrf2, attenuating its toxic and even its carcinogenic effects. Therefore, we have reviewed the scientific literature in order to indicate that air pollutants, such as particulate matter, polycyclic aromatic hydrocarbons, and gaseous matter, are Nrf2 pathway inductors, triggering self-defense through the establishment of proinflammatory and antioxidant responses. Results and discussion Exposure to reactive molecules as atmospheric pollutants causes the activation of Nrf2 and the subsequent regulation of the expression of cytoprotective and detoxifying enzymes, as well as antioxidants. Moreover, induction of Nrf2 prior to exposure reduces the harmful effects of pollutants. The present article discusses the protective role of the Nrf2 pathway against different atmospheric pollutant insults. Conclusions Nrf2 regulates the expression of numerous cytoprotective genes that function to detoxify reactive species produced during atmospheric pollutant metabolic reactions. From the papers highlighted in this review, we conclude that Nrf2 has an important role in the defense against atmospheric pollutant-induced toxicity. Perspectives Further studies are needed to understand the signaling events that turn on the system in response to atmospheric pollutant stress. This could allow for the possibility of targeting the pathway for prevention benefits in the near future.

BACKGROUND, AIM AND SCOPE: European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data. METHODS: A structure for an Information System for Monitoring GMO (ISMO) was developed by a multidisciplinary research team. It is based on the requirement to organise all relevant information in a logical, readily accessible and functional manner. RESULTS: For the ISMO, we present a combination of three interrelated components: Firstly, an ISMO should comprise a knowledge database structured according to information related to the different scale levels of biological organisation relevant to GMO monitoring and scientific hypotheses on cause–effects which should be validated by monitoring data. Secondly, a monitoring database should be part of an ISMO containing GMO-specific monitoring data and meta-data. This monitoring database should be linked with monitoring data from other monitoring programmes which are relevant for GMO-related questions. Thirdly, an ISMO should encompass a database covering administrative and procedural data. Neither national nor international approaches to an ISMO exist yet. CONCLUSIONS: An ISMO as designed in this paper could support competent authorities in both the GMO notification process and in post-market monitoring. This includes evaluating the environmental risks of experimentally releasing GMO and placing them on the market, assessing monitoring plans and evaluating monitoring results. The ISMO should be implemented on both the national and international level, preferably combining different administrative scales. Harmonisation approaches towards GMO monitoring data are at an initial stage, but they are a precondition to coordinated GMO monitoring and to successfully implementing an ISMO. It is recommended to set up a legal basis and to agree on common strategies for the data coordination and harmonisation.

Background, aim and scope Toxicity testing has become a suitable tool for wastewater evaluation included in several reference documents on best available techniques of the Integrated Pollution Prevention and Control (IPPC) Directive. The IPPC Directive requires that for direct dischargers as well as for indirect dischargers, the same best available techniques should be applied. Within the study, the whole effluent assessment approach of OSPAR has been applied for determining persistent toxicity of indirectly discharged wastewater from the metal surface treatment industry. Materials and methods Twenty wastewater samples from the printed circuit board and electroplating industries which indirectly discharged their wastewater to municipal wastewater treatment plants (WWTP) have been considered in the study. In all factories, the wastewater partial flows were separated in collecting tanks and physicochemically treated in-house. For assessing the behaviour of the wastewater samples in WWTPs, all samples were biologically pretreated for 7 days in the Zahn-Wellens test before ecotoxicity testing. Thus, persistent toxicity could be discriminated from non-persistent toxicity caused, e.g. by ammonium or readily biodegradable compounds. The fish egg test with Danio rerio, the Daphnia magna acute toxicity test, the algae test with Desmodesmus subspicatus, the Vibrio fischeri assay and the plant growth test with Lemna minor have been applied. All tests have been carried out according to well-established DIN or ISO standards and the lowest ineffective dilution (LID) concept. Additionally, genotoxicity was tested in the umu assay. The potential bioaccumulating substances (PBS) were determined by solid-phase micro-extraction and referred to the reference compound 2,3-dimethylnaphthalene. Results The chemical oxygen demand (COD) and total organic carbon (TOC) values of the effluents were in the range of 30-2,850 mg L⁻¹ (COD) and 2-614 mg L⁻¹ (TOC). With respect to the metal concentrations, all samples were not heavily polluted. The maximum conductivity of the samples was 43,700 µS cm⁻¹ and indicates that salts might contribute to the overall toxicity. Half of the wastewater samples proved to be biologically well treatable in the Zahn-Wellens test with COD elimination above 80%, whilst the others were insufficiently biodegraded (COD elimination 28-74%). After the pretreatment in the Zahn-Wellens test, wastewater samples from four (out of ten) companies were extremely ecotoxic especially to algae (maximum LIDA = 16,384). Three wastewater samples were genotoxic in the umu test. Applying the rules for salt correction of test results as allowed in the German Wastewater Ordinance, only a small part of toxicity could be attributed to salts. Considering the PBS, wastewater from the metal surface treatment industry exhibited very low levels of PBS. In one factory, the origin of ecotoxicity has been attributed to the organosulphide dimethyldithiocarbamate (DMDTC) used as a water treatment chemical for metal precipitation. The assumption based on rough calculation of input of the organosulphide into the wastewater was confirmed in practice by testing its ecotoxicity at the corresponding dilution ratio after pretreatment in the Zahn-Wellens test. Whilst the COD elimination of DMDTC was only 32% in 7 days, the pretreated sample exhibited a high ecotoxicity to algae (LIDA = 1,536) and luminescent bacteria (LIDlb = 256). Discussion Comparative data from wastewater surveillance by authorities (data from 1993 to 2007) confirmed the range of ecotoxicity observed in the study. Whilst wastewater from the metal surface treatment industry usually did not exhibit ecotoxicity (median LID 1-2), the maximum LID values reported for the algae, daphnia and luminescent bacteria tests were very high (LIDA up to 3,072, LIDD up to 512 and LIDlb up to 2,048). DMDTC was found to be one important source of ecotoxicity in galvanic wastewater. DMDTC is added in surplus, and according to the supplier, the amount in excess should be detoxified with ferric chloride or iron sulphate. The operator of one electroplating company had not envisaged a separate treatment of the organosulphide wastewater but was assuming that excess organosulphide would be bound by other heavy metals in the sewer. DMDTC degrades via hydrolysis to carbon disulfide (which is also toxic to animals and aquatic organisms), carbonyl sulphide, hydrogen sulphide and dimethylamine, but forms complexes with metals which stabilise the compound with respect to transformation. Although no impact on the WWTP is expected, the question arises whether the organosulphide is completely degraded during the passage of the WWTP. Conclusions and recommendations The results show that the organic load of wastewater from the electroplating industry has been underestimated by focussing on inorganic parameters such heavy metals, sulphide, cyanide, etc. Bioassays are a suitable tool for assessing the ecotoxicological relevance of these complex organic mixtures. The proof of biodegradability of the organic load (and its toxicity) can be provided by the Zahn-Wellens test. The environmental safety of water treatment chemicals should be better considered. The combination of the Zahn-Wellens test followed by the performance of ecotoxicity tests turned out to be a cost-efficient suitable instrument for the evaluation of indirect dischargers and considers the requirements of the IPPC Directive.

Background, aim, and scope In this study, a suite of sublethal stress biomarkers were analyzed in juveniles of the sentinel species, the Pacific oyster Crassostrea gigas, with a view to using them as pollution monitoring tools. The aim of this work was (1) to study baseline seasonal variations of biomarkers in different body compartments of C. gigas in the reference site and, after selecting biomarkers presenting no seasonal variations, (2) to compare responses of these biomarkers between contaminated and reference sites. Materials and methods Juvenile oysters were transplanted from Bouin (France), a reference site, to three different sites in Marennes-Oleron Bay (France), located in another water body and next to different contamination sources. Animals were exposed in situ for 3 months in summer, autumn, and winter. The following biomarkers were measured: superoxide dismutase (SOD) and glutathione peroxidase (GPx) in gills and digestive gland and lysozyme and phenoloxidase (PO) in plasma. Results No significant seasonal variations for SOD in gills and digestive gland, GPx in gills, and PO in plasma were observed in the reference site. Significant differences in enzyme activity were observed between contaminated and reference sites for SOD in gills and digestive gland and PO in plasma, depending on the body compartment, the season, and/or the site. Conclusions In conclusion, these data suggest the potential application of these biomarkers in C. gigas to provide ecologically relevant information and, therefore, to be used as biomarkers in coastal pollution monitoring.

Background, aim, and scope Two new high phenol-degrading strains, Micrococcus sp. and Alcaligenes faecalis JH 1013, were isolated. The two isolates could grow aerobically in mineral salts medium containing phenol as a sole carbon source at concentration of 3,000 mg L⁻¹. It was found that the binary mixed culture of the two isolates possessed good potential for phenol removal. Material and methods Phenol biodegradation using the binary mixed culture of the two isolates was studied. The optimal conditions were determined to be temperature 32°C, pH 7.0, inoculum size 10.0%, and agitation rate 150 rpm in the synthetic wastewater. In addition, the kinetics of the cell growth and phenol degradation by the binary mixed culture were also investigated using Haldane model over a wide range of initial phenol concentrations from 20 to 2,400 mg L⁻¹. Results The experimental data indicated that the binary mixed culture had pretty high phenol degradation potential, which could thoroughly degrade the phenol in the synthetic wastewater containing phenol 2,400 mg L⁻¹ within 72 h under aerobic condition. Under the optimal conditions, the phenol concentration was reduced speedily from 1,000 to below 0.28 mg L⁻¹ in the presence of the binary mixed culture, and the phenol degradation rate reached 99.97% after 16 h. It was well below the standard value 0.28 mg L⁻¹ as described by Chinese Environmental Protection Agency. It was clear that the Haldane kinetic model adequately described the dynamic behavior of phenol degradation by the binary mixed culture with kinetic constants of q max = 0.45 h⁻¹, K sq = 64.28 mg L⁻¹, and K iq = 992.79 mg L⁻¹. The phenol concentration to avoid substrate inhibition had been inferred theoretically to be 252.62 mg L⁻¹. Conclusions Phenol, as the only carbon source, could be degraded by the binary mixed culture at high initial phenol concentrations. Phenol exhibited inhibitory behavior, and the growth kinetics of the binary mixed culture could be correlated well by the simple Haldane's inhibitory model. The kinetics parameters were invariably required for the design and simulation of batch and continuous bioreactor treating phenolic wastewaters.

Background, aim and scope A newly developed fine bubble aeration system, by which air is transferred under supercavitation conditions, shows a clearly better performance than traditional, well-known aerators that rely on the jet-pump principle and its performance can be compared to oxygen transfer rates achieved in membrane and foil plate aerators. Materials and method A prototype supercavitation aerator installed at a sewage treatment plant revealed an air input rate, which was about one third lower than that of the jet-pump system, which it replaced. Results In spite of this low air input rate, the daily demand of pure oxygen for the additionally installed membrane aeration system went down by approximately 49%, from the original level of about 1,200 m³/day to about 600 m³/day—and this over a test period of more than 7 months. Conclusions and discussion The observed high oxygen transfer rates cannot be explained by traditional mass transfer mechanisms. It is assumed that a large amount of water being transferred into the gas phase by supercavitation contacting directly oxygen also in the gas phase and thereby overcoming mass transfer hindrances which might be favoured by hydroxyl radicals. With this new aerator, during the first 3 months of test phase, already more than 10,000 Euros had been saved because of the reduced pure oxygen demand.

Background, aim and scope The paper presents concentrations of trace elements in blood of homebred animals (cows and sheep) from Southern Serbia (Bujanovac) and the contents of natural and anthropogenic radionuclides and some heavy metals in feed. The region of Southern Serbia was exposed to contamination by depleted uranium ammunition during NATO attacks in 1999 and therefore, is of great concern to environmental pollution and human and animal health. Materials and methods Conventional instrumental and epithermal neutron activation analyses are used to measure trace elements in cow and sheep blood samples collected randomly at six locations in the region of Bujanovac (village of Borovac) in the spring of 2005. Samples of feed (grass and crops: corn, wheat and oats), collected on the same locations (households), are analysed for the contents of radionuclides on an HPGe detector (Ortec, relative efficiency 23%) by standard gamma spectrometry. The content of Hg, Pb and Cd in feed is determined by standard atomic absorption spectrometry on the VarianSpectra220/ThermoSolar GFS97 spectrometer. Results Concentrations of 29 elements (Na, Al (P), Cl, K, Sc, Cr, Mn, Ni, Fe, Co, Zn, Se, As, Br, Sr, Rb, Sb, In, I, Ba, Cs, La, Nd, Eu, Sm, Tb, Hf, Ta and Th) are determined in blood of the examined animals. In feeds, natural ⁴⁰K is found in all of the samples, cosmogenic ⁷Be and fission product ¹³⁷Cs are detected only in the grass samples, while heavy metals Hg, Cd and Pb are found in the range of 0.01-0.02, 0.84-1.15 and 0.74-7.34 mg/kg, respectively. Calculated soil-to-blood transfer factors are in a wide range of 8·10⁻⁶ to 64, as a result of varying significance of the elements in animal metabolism and feeding habits. Discussion The results of trace elements' concentrations in animal blood are in good agreement with available data for K, Ni, Zn, Se and Rb. Higher Br concentrations in animal blood are most probably caused by large biomass burning events during blood sampling. Very low concentration of Fe in cows and sheep confirms the results of previous biochemical studies on animal anaemia in the region. High concentration of As correlates with geochemical peculiarities of the Balkans and is also likely influenced by the use of pesticides in the agricultural production. For some of the elements (La, Nd, Eu, Sm, Tb, Sb, Hf, Ta, Th, In, Ba, Sr, Sc and Cs), there are few or no literature data. Therefore, some of the presented data are significant not only for the country and the region, but on a wider scale. Activities of natural radionuclides in feeds are within the average values reported for the region, while the activities of ²¹⁰Pb and ²³⁵/²³⁸U are below the limit of detection. This is in accordance with previous investigations showing no widespread contamination by depleted uranium in the area. Contents of Hg and Pb in feeds are below the nationally permissible levels, unlike the content of Cd which exceeds it, probably caused by the use of phosphate fertilisers and fossil fuel combustion in the area. Conclusions In general, the concentrations of trace elements in blood of homebred cows and sheep are in good agreement with reference materials, available literature data and the results of previous studies in the area. The exceptions are Fe, As and Br. The contents of natural and anthropogenic radionuclides in feeds are within the expected levels, and there are no signs of contamination by depleted uranium or other fission products. Apart from Cd, there are no signs of pollution by heavy metals in feeds. The highly sensitive method of instrumental neutron activation analysis provides data on the concentration of some elements in animal blood not previously reported for the region and elsewhere. Recommendations and perspectives The presented study is a part of the long term ongoing project on the health risk assessment on animals and humans in the region. The collected data is intended to provide a base for the animal and human risk assessment as well as an estimate of the general pollution status of the environment in the region. Since some of the investigated elements are classified as important trace elements for livestock, the results could also be used to balance and improve the animal diet and thus, improve the growth and reproduction rate.

Background The Atacama Desert in Northern Chile is one of the most arid places on earth. However, fog occurs regularly at the coastal mountain range and can be collected at different sites in Chile to supply settlements at the coast with freshwater. This is also planned in the fog oasis Alto Patache (20°49′S, 70°09′W). For this pilot study, we collected fog water samples in July and August 2008 for chemical analysis to find indications for its suitability for domestic use. Methods Fog water samples were taken with a cylindrical scientific fog collector and from the net and the storage tank of a Large Fog Collector (LFC). Results The pHs of advective fog, originating from the stratus cloud deck over the Eastern Pacific, varied between 2.9 and 3.5. Orographic fog, which was formed locally, exhibited a pH of 2.5. About 50% of the total ionic concentration was due to sea salt. High percentages of sulfate and very high enrichment factors (versus sea salt) of heavy metals were found. Both backward trajectories and the enrichment factors indicate that the high concentrations of ions and heavy metals in fog were influenced by anthropogenic activities along the Chilean Pacific Coast such as power plants, mining, and steel industry. Conclusions We found no direct indication for the importance of other sources such as the emission of dimethyl sulfide from the ocean and subsequent atmospheric oxidation for acidity and sulfate or soil erosion for heavy metal concentrations. When fog water was collected by the LFC, it apparently picked up large amounts of dry deposition which accumulated on the nets during fog-free periods. This material is rinsed off the collector shortly after the onset of a fog event with the water collected first. During the first flush, some concentrations of acidity, nitrate, As, and Se, largely exceeded the Chilean drinking water limits. Before any use of fog water for domestic purpose, its quality should be checked on a regular basis. Strategies to mitigate fog water pollution are given.

Background, aim and scope In an international project named MONARPOP (Monitoring Network in the Alpine Region for Persistent and other Organic Pollutants), selected chemicals in different environmental media were analysed in the years 2004 and 2005. Seventeen pesticides were chosen and analysed in humus and mineral soil in the German Alps. The samples were taken at different altitudes. Materials and methods In such a rather complex environmental datasets, it is often necessary to compare different sets of criteria and their influence on rankings. In the similarity analysis which is part of the theory of the Hasse diagram technique, we intend to calculate the similarity of different rankings. Furthermore, we perform a so-called dominance-dominance/dominance-separability method, followed by a sensitivity analysis, both subroutines in the newly developed PyHasse programme in order to find out if the concentration of the chemicals can be related to the altitudes at which the samples were taken. Results and discussion It can be demonstrated that the altitude has a considerable influence on the concentration of some organic chemicals in humus: The concentrations of some chemicals increase with the altitude. This increase shows certain irregularities for which several explication attempts including possible effects of atmospheric stratification phenomena in valleys have been made. Conclusion These results should be complemented in further studies with MONARPOP monitoring data from other Alpine countries, e.g. Austria, Switzerland, Italy and Slovenia.