Simultaneous measurements of gaseous SO2, NO2, HNO3, NH3 and particulate SO42–, NO3– and NH4+ were carried out in a suburban area in Cairo during summer 2009 and winter 2009–2010. PTFE membrane filters were used to collect particulate SO42–, NH4+ and NO3–, followed by the impregnated filter to collect HNO3. Colorimetric methods were used for determination of NO2, SO2, NH3, SO42–, NH4+ NO3–, and HNO3 levels. The mean concentrations of NO2, SO2 and NH3 were 75.0, 40.1 and 29.1 µg/m3 in winter and 54.1, 25.1 and 44.9 µg/m3 in summer, respectively. The daytime/nighttime concentration ratios were 1.3 and 1.2 for NO2, 1.3 and 1.2 for SO2 and 0.6, and 0.8 for NH3 during the winter and summer, respectively. The mean values of NH4+, SO42–, NO3–, HNO3 and total NO3– were 4.4, 19.0, 3.4, 1.1 and 4.5 µg/m3 in winter and 7.5, 28.0, 4.2, 3.1 and 7.3 µg/m3 in summer, respectively. The levels of NH4+, SO42–, NO3– and HNO3 were relatively higher in daytime than in nighttime. Sulfur conversion (Fs) and nitrogen conversion ratios (Fn) in summer were about 1.78 and 2.15 times higher than in winter, respectively. Fs and Fn were higher in daytime than in nighttime. Significant positive correlation was found between Fs and relative humidity. The positive correlation between Fn and relative humidity was insignificant. The correlation between the concentration of NH4+ and NO3– indicates that NO3– may be found in fine mode (NH4NO3) in winter and it may be present predominantly as a coarse mode, such as Ca(NO3)2, Mg(NO3)2 and NaNO3 in summer. The concentration of SO42– was significantly correlated with NH4+ concentration, suggesting neutralization by NH3 and indicating that the forms of (NH4)2SO4 and/or NH4HSO4 exist in the aerosol. The NH4+/SO42– molar ratio indicates that SO42– in aerosol may be present as (NH4)2SO4, (NH4)2SO4.CaSO4.2H2O and CaSO4.

Size selective particulate matter (PM) sampling inlets play an important role in ambient PM measurement. Improper design of the sampling inlets results in collecting of PM with undesired size, which leads to significant errors in the measurement of ambient PM concentrations. Therefore, the performance of PM inlets should be carefully evaluated in a proper environment prior to their field of applications. In this study, a new aerosol wind tunnel system was designed to evaluate the performance of ambient PM10 inlets and evaluated for the uniformity of wind speed distribution and aerosol concentration. In addition, a custom–made PM10 inlet was tested in the aerosol wind tunnel to determine its 50% cutoff diameter. Results of the wind speed distributions show that the percentage deviations from the mean wind speeds at any measurement point are less than 10% with turbulence intensity of less than 5% for three different wind speed levels (0.57m/s, 2.22m/s, and 6.67m/s). Results from the aerosol concentration measurements show that the percentage deviations from the mean aerosol concentrations at any measurement point are less than 10% for three different wind speed levels, which meets the aerosol wind tunnel performance specifications specified by the U.S. Environmental Protection Agency (EPA). Results from PM10 inlet performance tests show that the 50% cutoff diameters of the PM10 inlet are 10.0 μm, 10.3 μm, and 10.0 μm at wind speeds of 0.57m/s, 2.22m/s, and 6.67m/s, respectively. The PM10 inlet is characterized to meet the performance specifications for PM10 inlets, 10.0±0.5 µm, specified by the U.S. EPA. The results indicate that the newly developed aerosol wind tunnel meets the performance requirements for evaluating the performance of PM10 size selective inlets.

Air pollution control strategies have helped to improve the air quality over Europe over the last twenty years. Despite this success, the improvements have been insufficient to protect health of those who spend most of their time within urban areas and particularly near major roads. Given the inherent complexity of urban environments and the incomplete understanding of the physical and chemical processes involved in pollutant dispersion, it is a challenging task to estimate urban air quality. In order to address this issue, a new regression model for estimating the urban increment for all cities of a region up to Europe as a whole is developed. The model is able to capture the higher pollutant concentrations commonly found within urban areas for assessing the localized effects associated to urban emissions. This approach is used for estimating annual concentrations of PM10 and NO2 for all urban areas with more than 50 000 inhabitants in Germany for the reference year 2005. The results showed that there are differences on air quality levels across urban areas in Germany. This information is relevant when evaluating the impact of emission reduction policies on air quality, which should take into account the cost–benefit of each measure. Furthermore, as the modelling approach allows for flexibility changing initial conditions and building scenarios, the added values of this approach are the large spatial domain covered, the high spatial resolution, and its inherent flexibility to address other environmental issues, such as analysis of emission reduction scenarios, the human exposure to certain pollutants and their associated human health impacts.

The sources, distribution and risk of 51 organic micropollutants (OMPs) in the Cantabrian coastal environment (NW Spain) were evaluated. Gas chromatography coupled to tandem mass spectrometry was used to determine polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorinated pesticides, polybrominated diphenyl ethers, phthalates esters, bisphenol A and alkylphenols. 45 OMPs were detected in coastal/estuarine waters. Wastewater treatment plant effluents and emissary discharges were identified as the main sources of contamination. The accumulation of OMPs in sediments and the bioaccumulation in 21days caged mussels were also assessed. Chemical results were combined with the “Combined Monitoring-based and Modeling-based Priority Setting Scheme” COMMPS procedure for risk assessment analysis. Finally, the chemical status of the different sampling locations was estimated using site risk indexes. Those indexes can be conveniently displayed in quality geographical maps and are considered a valuable tool for the environmental management and risk assessment of the region under study.

Metals and biogenic elements were analyzed from surface sediments collected from Zhelin Bay in the South China Sea in December 2008. The high concentrations of TOC, TN and BSi indicate the high nutrient level and diatom productivity in Zhelin Bay. The concentrations of metals were generally far lower than the effects-range-low (ERL) values that define pollutant levels. Enrichment factors (EF) and geoaccumulation indices (Igeo) suggest there are pollution levels of Cd, Cu and Zn at some stations. As, Cu, and Pb are potentially biotoxic in some stations. Correlation and principal component analyses indicate that most of the metals primarily originate from natural sources, and from maricultural activities as well. Mariculture contributes considerable Cd and Cu contamination. As and Pb comes primarily from combustion of gasoline and diesel fuel by ships.

This paper presents a simulated marine oil spill bioremediation experiment using a bacterial consortium amended with rhamnolipids. The role of rhamnolipids in enhancing hydrocarbon biodegradation was evaluated via GC–FID and GC–MS analysis. Rhamnolipids enhanced total oil biodegradation efficiency by 5.63%, with variation in normal alkanes, polyaromatic hydrocarbons (PAHs) and biomakers biodegradation. The hydrocarbons biodegradation by bacteria consortium overall follows a decreasing order of PAHs>n-alkanes>biomarkers, while in different order of PAHs>biomarkers>n-alkanes when rhamnolipids was used, and the improvement in the removal efficiency by rhamnolipids follows another order of biomarkers>n-alkanes>PAHs. Rhamnolipids played a negative role in degradation of those hydrocarbons with relatively volatile property, such as n-alkanes with short chains, PAHs and sesquiterpenes with simple structure. As to the long chain normal alkanes and PAHs and biomakers with complex structure, the biosurfactant played a positive role in these hydrocarbons biodegradation.

The influence of different concentrations (10–2000μM) of heavy metals (Cu, Mn, Ni, Zn) was analysed in Atriplex halimus and Salicornia ramosissima germination pattern and seedling size. They are two halophyte species that grow in the Estuary of Huelva (Southwest Iberian Peninsula, Spain), one of the most heavy metal-polluted environments in the world.All of the metals tested affected the final germination percentage in A. halimus and only Ni reduced germination in S. ramosissima. The germination rate was unaffected in both species.The study of seedling development shows that S. ramosissima, an intertidal annual species, has a higher tolerance of metals than A. halimus, a bush that inhabits the upper part of the marshes.Taking into account the metal concentrations in the estuary and the effects of these on the seedling development of the species analysed, we conclude that metals might limit plant colonisation in some parts of the marshes.

The health status of an emerging Posidonia oceanica meadow, subject to high human impact, was studied. Biometric variables, heavy metals, PAHs and C, N, P contents were determined in sediment and seagrass samples. The meadow was found to grow under oligotrophic conditions and an increase in nutrient content was only recorded in autumn. In sediment, Hg exceeded its ERL (effects range low) and sometimes also its ERM (effects range medium), and Cu was close to its ERL. In leaves, Hg and Cu were relatively high but below their respective ERLs. Sediments close to the meadow were heavily contaminated with pyrolytic PAHs, some of which exceeded their ERLs. P. oceanica did not show major accumulation of PAHs, lighter molecules predominating. Despite 40years of intense human activity, meadow growth dynamics and contaminant accumulation did not suggest that the meadow was regressing.

Mediterranean coastal regions are particularly exposed to oil pollution due to extensive industrialization, urbanization and transport of crude and refined oil to and from refineries. Bioremediation of contaminated beach sand through landfarming is both simple and cost-effective to implement compared to other treatment technologies. The purpose of the present study was to investigate the effect of alternative nutrients on biodegradation of crude oil contaminated beach sand in an effort to reduce the time required for bioremediation employing only indigenous hydrocarbon degraders.A natural sandy soil was collected from Agios Onoufrios beach (Chania, Greece) and was contaminated with weathered crude oil. The indigenous microbial population in the contaminated sand was tested alone (control treatment) or in combination with inorganic nutrients (KNO3 and K2HPO4) to investigate their effects on oil biodegradation rates. In addition, the ability of biosurfactants (rhamnolipids), in the presence of organic nutrients (uric acid and lecithin), to further stimulate biodegradation was investigated in laboratory microcosms over a 45-day period.Biodegradation was tracked by GC/MS analysis of aliphatic and polycyclic aromatic hydrocarbons components and the measured concentrations were corrected for abiotic removal by hopane normalizations. It was found that the saturated fraction of the residual oil is degraded more extensively than the aromatic fraction and the bacterial growth after an incubation period of approximately 3weeks was much greater from the bacterial growth in the control.The results show that the treatments with inorganic or organic nutrients are equally effective over almost 30days where C12–C35n-alkanes were degraded more than 97% and polyaromatic hydrocarbons with two or three rings were degraded more than 95% within 45days. The results clearly show that the addition of nutrients to contaminated beach sand significantly enhanced the activity of indigenous microorganisms, as well as the removal of total recoverable petroleum hydrocarbons (TRPH) over a 45-day study period.

Satellite remote sensing technology has a great potential to measure the properties of atmosphere and has shown marked advancements through the last decade, in monitoring nitrogen oxide species (NOX) in troposphere. NO2 in troposphere is one of the key factors which determine the air quality and has serious implications on human health and plant growth. It is also well known for its indirect contribution to climate change. The identification of spatial and temporal variations of NO2 is necessary for any effective mitigation plan to curb its obnoxious abundance. Tropospheric NO2 measurements provided by the satellite remote sensor “SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY” (SCIAMACHY) are utilized here to identify the regions across India where a concentration of NO2 exceeds the permissible healthy level. A new approach based on empirical approximation is attempted to normalize the unit of satellite measurement with the unit of existing air quality standard. Trend analysis for all the regions are carried out by means of a non–linear regression method. The geospatial and statistical analysis of monthly tropospheric NO2 data from the full operational period of SCIAMACHY (2002 August–2012 March) have resulted in the identification of 12 hot spot regions across India among which most of them exhibited a significant increasing trend. Some of the rural districts which were not previously implicated for NO2 pollution risk are also recognized here. This study illustrates the possibility of the use of satellite measurements in air quality monitoring and management in regional spatial scale. The effects of seasonal climatic changes in India on the ambient NO2 pollution level are also explained.