The efficiency of several lab scale treatments (aerobic, anaerobic and ozone or combination of these) was evaluated using two packaging board mill whitewaters. The effect of the different treatments on the elimination of the organic load, the chemical oxygen demand (COD) and the toxicity was tested as well as the relationship between these parameters. Biocides, phenolic compounds, surfactants, plasticiziers and wood extractives were identified in untreated and treated whitewaters by liquid chromatography coupled with mass spectrometry (LC-MS) or gas chromatography coupled with mass spectrometry (GC-MS). A strong dependency on the water type and treatment efficiency was observed, being the combination of anaerobic and aerobic treatments the best option to reduce the organic contaminants in these waters, although in some cases, the toxicity did not decrease. However, ozone as post-treatment permitted a further reduction of organic compounds, toxicity and COD. Aerobic and anaerobic treatments remove organic compounds in paper mill effluents but toxicity remains.

8 pages, 3 figures, 1 table.-- PMID: 17118260 [PubMed].-- Online version available Nov 20, 2006. | Issue title: Air Pollution and Climate Change: A Global Overview of the Effects on Forest Vegetation. | The efficiency of several lab scale treatments (aerobic, anaerobic and ozone or combination of these) was evaluated using two packaging board mill whitewaters. The effect of the different treatments on the elimination of the organic load, the chemical oxygen demand (COD) and the toxicity was tested as well as the relationship between these parameters. Biocides, phenolic compounds, surfactants, plasticiziers and wood extractives were identified in untreated and treated whitewaters by liquid chromatography coupled with mass spectrometry (LCeMS) or gas chromatography coupled with mass spectrometry (GCeMS). A strong dependency on the water type and treatment efficiency was observed, being the combination of anaerobic and aerobic treatments the best option to reduce the organic contaminants in these waters, although in some cases, the toxicity did not decrease. However, ozone as post-treatment permitted a further reduction of organic compounds, toxicity and COD. | Aerobic and anaerobic treatments remove organic compounds in paper mill effluents but toxicity remains. | This study has been supported by the EU Energy, Environmental and Sustainable Development Program (CLOSEDCYCLE, Contract No EVK1-2000-00749). The authors thank Riudesa factory (Catalonia, Spain) and Anox (Sweden) for supplying water samples and Merck for supplying the LC columns. | Peer reviewed

Trends were found for increasing surface ozone concentrations during April-September in northern Sweden over the period 1990-2006 as well as for an earlier onset of vegetation growing season. The highest ozone concentrations in northern Sweden occurred in April and the ozone concentrations in April showed a strong increasing trend. A model simulation of ozone flux for Norway spruce indicated that the provisional ozone flux based critical level for forests in Europe is exceeded in northern Sweden. Future climate change would have counteracting effects on the stomatal conductance and needle ozone uptake, mediated on the one hand by direct effect of increasing air temperatures and on the other through increasing water vapour pressure difference between the needles and air. Thus, there is a substantial and increasing risk for negative impacts of ozone on vegetation in northern Sweden, related mainly to increasing ozone concentrations and an earlier onset of the growing season. Increasing risks for ozone impacts on vegetation in northern Sweden.

Air quality is strongly dependent on meteorological conditions. Atmospheric circulation encapsulates general information about local meteorological variables to some extent, and can serve as an explanatory variable for air quality at a regional or local scale. Numerical models are another useful tool for understanding the influence of meteorological factors on the chemical and physical processes involved in regional and local air quality variations. The aims of this thesis have been to: (1) investigate regional surface ozone and its correlation to atmospheric circulations by making use of synoptic weather types in southern Sweden; (2) compare numerical models performances in simulating urban meteorological conditions and apply a numerical model to urban air quality study for Gothenburg. The study confirmed the influences of synoptic circulation on regional ozone concentrations by relating the Lamb Weather Types (LWTs) to surface ozone variations. Anticyclones, associated with atmospheric stagnation, tend to create whirling air masses and short trajectories from the European continent, which leads to effective long-range transport, enhanced local ozone photochemical production, and high-ozone levels. Cyclones, on the other hand, can also create high level ozone through frontal passages and enhanced vertical mixing. At the same time, the frequencies of cyclones and anticyclones in this region are highly anti-correlated, making cyclone frequency a skilful predictor of high ozone events. The frequency of cyclones over the past 150 years shows a high variability and showed significantly downward trend. Given the constant conditions from other factors for example emission, continuous decrease in the frequency of cyclones indicates the more occurrences of high-ozone events in southern Sweden. A numerical model - The Air Quality Model (TAPM) - was used to simulate the complex wind system and other meteorological variables needed for air quality applications in the Gothenburg area. Compared with The PSU/NCAR fifth-generation Mesoscale Model (MM5), TAPM is able to better reproduce near-surface air temperature and wind system in Gothenburg. Both MM5 and TAPM can simulate night-time vertical temperature gradient well, but underestimate daytime vertical temperature gradient and the occurrences of low wind speed situation at night. TAPM was then used to reproduce NOx−O3 reactions and investigate the wind speed effect on spatial differences of NO2 concentrations in the polluted urban landscape. TAPM satisfactorily simulated the relation of NO, NO2 and ozone as well as the site differences for different wind speed categories. However, TAPM underestimated NO at certain sites due to local scale sitespecific conditions and missing emissions from nearby roads and other emission sources.

[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / HYDRECO | International audience | Scats of the European otter (Lutra lutra) were sampled along the Allier river (France) catchment for organochlorine toxic compounds (nine pesticides and 16 PCBs congeners) measurement. From early 2004 to June 2005, 90 sites of 40 rivers were twice investigated, and 71 scats samples collected, in four geographical areas being naturally re-colonized by the species since its legal protection. Detectable pesticides and PCBs were found in 100% of the samples. Mean values reached 2.72 and 13.58 mg kg-1 (lipid weight) for pesticides and PCBs, respectively. Amounts were significantly different between the four areas investigated. A significant increase in medium and absolute values is noted by going downstream of the catchment. Potential medium- and long-term consequences on the observed population increase are discussed.

Scats of the European otter (Lutra lutra) were sampled along the Allier river (France) catchment for organochlorine toxic compounds (nine pesticides and 16 PCBs congeners) measurement. From early 2004 to June 2005, 90 sites of 40 rivers were twice investigated, and 71 scats samples collected, in four geographical areas being naturally re-colonized by the species since its legal protection. Detectable pesticides and PCBs were found in 100% of the samples. Mean values reached 2.72 and 13.58 mg kg-¹ (lipid weight) for pesticides and PCBs, respectively. Amounts were significantly different between the four areas investigated. A significant increase in medium and absolute values is noted by going downstream of the catchment. Potential medium- and long-term consequences on the observed population increase are discussed.