Typical mid-winter anthropogenic air pollution episodes are caused when pollutants are trapped in the lower atmospheric boundary layer due to the generation of surface inversion favored by synoptic conditions. We analyzed the optical properties of atmospheric aerosol particles obtained during one such episode using a sun/sky radiometer at two measurement sites: one located in the densely populated and industrialized central part of Israel, and the other in a reference site, about 150 km away. Aerosol optical thickness and volume size distributions showed an increased burden of fine aerosol particles in the central part of Israel. In order to verify the local origin and anthropogenic nature of the effect, the analysis was accompanied by examinations of the synoptic conditions, air mass backward trajectories, and conventional in situ air pollution measurements made by a ground-based sampling station. This case study shows the ability of optical measurements to track urban and industrial atmospheric air pollution expressed by high concentration of fine aerosol particles. In addition, it emphasizes the role of local Israeli air pollution sources and may explain the difference in the properties of long-term aerosol optical observations between the two sites. The advantages of the optical method presented are speed (almost instantaneous), automated measurement, and sensitivity to aerosol particle concentration as well as aerosol size fraction. The drawback is that the optical measurements discussed deal only with aerosol particles and cannot distinguish between different types of pollutant gases.

Chemical composition of fog and rain water was studied during a 47-day experimental period. The differences between the fog and rain water were found to be significantly for most analyzed ions. H⁺, NH₄ ⁺, NO₃ -, and SO₄ ²- made up 85% of the total median ion concentration in fog and 84% in rain water. The total mean equivalent concentration was 15 times higher in the fog than in the rain water. The fog water samples were classified according to their air mass history. The analysis of the 120 h backward trajectory led to the identification of three advection regimes. Significant differences of ion concentrations between the respective classes were found. Air masses of class I travelled exclusively over the Pacific Ocean, class II were carried over the Philippines, and class III were advected from mainland China. The turbulent fog water deposition was determined by the means of the eddy covariance method. The total (turbulent plus gravitational) fog water fluxes ranged between +31.7 mg m-² s-¹ and -56.6 mg m-² s-¹. Fog water droplets with mean diameters between 15 μm and 25 μm contributed most to the liquid water flux. The sample based nutrient input was calculated on the basis of the occult and wet deposition, and the concentrations of the simultaneously collected fog and rainwater samples, respectively. The nutrient input through wet deposition was about 13 times higher than through occult deposition.

The application of magnetite-immobilized chitin in pentachlorophenol (PCP) removal was demonstrated in this study. The physicochemical parameters for immobilization of chitin by magnetite, and for PCP adsorption using magnetite-immobilized chitin were optimized. For chitin immobilization, the optimized conditions were: magnetite to chitin (m:c) ratio at 1:2, initial pH 6, 25°C, 200 rpm and 60 min in batch system. The immobilization efficiency (IE) was 99.4% and immobilization capacity (IC) was 2.0 mg chitin mg-¹ magnetite. High initial pH (pH > 11) and temperature (>30°C) lowered the IE and IC. For PCP (10 mg l-¹) adsorption, the optimized conditions were: 1,500 mg l-¹ immobilized chitin, initial pH 6, 25°C, 200 rpm and 60 min in batch system. The removal efficiency (RE) was 57.9% and removal capacity (RC) was 5.4 mg g-¹. The adsorption ability of immobilized chitin decreased with pH and temperature increased. However, increasing the amount of immobilized chitin (24,000 mg l-¹) can increase the RE up to 92%. Both chitin immobilization and PCP adsorption exhibited Langmuir and Freundlich adsorption isotherms. Results in this study indicated that magnetite-immobilized chitin was a cost-effective and environmental friendly adsorbent to remove environmental pollutants such as PCP.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in the urban atmosphere. In particular, atmospheric pollution has increasingly become severe in China due to its rapid urbanization and industrialization. In recent years, a few studies have presented information about POPs (such as PAHs, PCBs, OCPs) in aerosols at a molecular level in a limited number of cities such as Beijing, Qingdao and Guangzhou, as well as Hong Kong. Whereas, these cities are located in northern and southern China, respectively, where characteristics of atmospheric pollution might be different from those in the eastern cities, such as Shanghai. Atmospheric particle pollution is a persistent problem in Shanghai, a typical metropolis of China, which has several huge industrial regions. In order to gain a comprehensive understanding of the present state, properties and sources of PAHs pollution in Shanghai, PM₁₀ samples were collected at Coal-Fired Power Plant (CFP), Chlor-Alkali Chemical factory (CAC) and Coking and Chemical factory (CCF) in an industrial area, during the period, November 2004-September 2005. The concentrations of 16 PAHs were analyzed using the HPLC with UV visible detector. The results showed that the mean value of total PAHs in the industrial area was 64.85 ng m-³; 3-ring PAHs were found at low levels, while 4-, 5- and 6-ring PAHs were found at high levels. The levels of BaP were 3.07 and 7.16 ng m-³ at Chlor-Alkali Chemistry Factory and Coking and Chemistry Factory sites, respectively. PAHs levels exhibited distinct seasonal variation, with the highest level in autumn and the lowest in summer. The major source of PAHs at the industrial area was fossil fuel combustion, coal-burning, industrial furnaces including others. There was a very significant correlation of PAHs levels between CCF and CAC (R ² = 0.91). The average concentration of BaP in the industrial area during the sampling period was 5.95 ng m-³. It could be concluded the local population appears to be exposed to significantly high cancer risk (exceeding 2 ng m-³ in autumn and winter) as compared to the population of other areas.

The bursting of the mining dam of Aznalcollar (Seville, Spain) triggered an increase in the concentration of heavy metals in the soils of the river Guadiamar valley as a result of the leaching of the pyritic sludge deposited on them. After the cleaning operations which included, as well as mechanical clearing, the addition of different amendments, some areas with residual sludge remained, from which some heavy metals are being mobilized by the cyclical recharge and discharge processes of water in the profiles. This paper analyzes the effect of the soil recovery operations and the climatology on the concentration of metals and their distribution in the soil profile in an area affected by the toxic spill. Fourteen points have been selected in a plot in which acidity persists, there is no vegetation, and residual sludge stains can be seen at a glance. The temporal and spatial evolution of the extractable metals: Fe, Cu, Mn and Zn, the pH and the oxidable fraction has been measured in-depth. The results obtained up to now indicate a leaching of the pollutant towards deeper horizons, finding, at a depth of 757 cm, pH values of 3.5 and very high Fe and Mn concentrations available, especially in the profiles with large sized pores, with a big fraction of sand. On the surface, seasonally, there are low pH values of around 2.5 and extractable Fe contents of over 4000 ppm, which might have an influence on the quality of surface runoff or underground water.

Polycyclic aromatic hydrocarbons (PAHs) are considered to be atmospheric pollutants and well-known human carcinogens. This study analyzes the pollution scenarios of PAHs in the aerosol of Higashi Hiroshima, Japan. We examined the characteristics, the influences of meteorological conditions, the distribution and seasonal variation of PAHs in aerosol samples collected from June 2000 to May 2001. The concentration of PAHs in the aerosol of Higashi Hiroshima was ranging from 11.8 to 157.5 μg/g with a mean concentration of 63.4 μg/g. Results showed that there is positive correlation between aerosol PAH concentrations and ambient temperature but a relatively little correlation with solar radiation. Seasonal variation was observed with a higher concentration during winter and lower concentration during summer. Apart from that, principal component analysis and molecular diagnostic ratios were also used to characterize and identify possible PAHs emission sources. Results obtained strongly suggested that vehicular emissions appeared to be the major source of aerosol PAHs in this study although other sources do have some degree of influence.

Rapid field-based screening methods for the semi-quantitative determination of heavy metals are desirable to support the increasing demand for the rapid characterization of contaminated sites. Single-use sensors have been fabricated using low-cost screen-printing (thick film) technology. These electrodes, coupled with differential pulse anodic stripping voltammetry (DPASV), have provided a rapid, inexpensive on site screening device for the simultaneous field-based determination of cadmium (Cd) and lead (Pb) in soil and water samples in the microgram per litre/kilogram range. A simplified soil extraction procedure, using 1 mol l-¹ aqua regia and a 3 min ultrasonic sample agitation, has been developed to allow field-based device usage. Extraction efficiency was evaluated using a soil certified reference material (CRM). Recoveries of 64% and 52% for Cd and Pb respectively were obtained, with a relative standard deviation (RSD) of <8% for both analytes (n = 10). Soil samples (82) were tested using the combined extraction-DPASV procedure and compared against standard ICP-AES analysis. Correlation coefficients of 0.9782 and 0.9728 for Cd and Pb respectively demonstrate good correlation between methods. Analytical data is also reported for copper (Cu), but significant peak distortions reduce the confidence of the method for this metal. Results indicate that the combined extraction-DPASV method yields semi-quantitative data for rapid field-based site screening purposes.

The importance of the chemical composition in evaluating groundwater flow is discussed. Two different geological environments, a felsic volcanic region around San Luis Potosí (SLPB), Mexico, and a sedimentary basin, part of the Pannonian Basin (PB), in Hungary, were chosen to explore the effect of local, intermediate and regional groundwater flows on the chemical evolution of water in different geological circumstances. In the study areas contrasting stable isotopes and groundwater temperature values, as well as the chemical composition of groundwater were convenient tools to propose groundwater flow direction and to study contamination processes in the different groundwater flow systems. Results indicate that regardless of the geological framework variability of the chemical composition of the shallow (<100 m) groundwater is significant; at depth the chemical content of groundwater becomes homogeneous, and the concentrations are smaller than at shallow depths. The Cl- and NO- ₃ concentrations indicate mainly up- and downward vertical flow directions suggesting local flow systems in the shallow layers. The linear regression between Cl- and Na⁺ suggests that evaporation processes are the main control of the Cl- concentration. Deviations from the regression line suggest processes such as pollution at shallow depths in both study areas. Based on the distribution of Ca⁺², Mg⁺² and Na⁺, a lateral flow can be traced. The large dimensions of the geological units involved with the regional flow systems implies a long groundwater flow path, also these flows remain isolated from anthropogenic contamination, then groundwater has not been altered by human influence, although in the SLPB a communication between the local and intermediate flows has been found. Recharge areas of the local and intermediate flow systems are more vulnerable to contamination processes than the discharge areas, where the expected low dissolved oxygen content of ascending water could play a control. Differences in the lithology between the PB (sedimentary basin) and the SLPB (felsic volcanic basin) explain the contrasting saturation indices calculated for chalcedony and calcite and the lack of the expected development of HCO- ₃, SO-² ₄ Cl- facies and contrasting aerobic/oxidizing conditions.

Siderophores are small molecular weight extracellular organic compounds secreted by microorganisms under iron-starved conditions, used by them to chelate and solubilize iron. Though they are specific ferric iron chelator, but is reported that they bind other metals also, such as divalent heavy metals and actinides because of potentially high metal-siderophore stability constants. Thus metal contaminant fate and transport in subsurface environment can be heavily influenced by siderophores. This approach can be successfully used in removing many toxic metals off the soil which poses a serious health threat. Our research focuses on the correlation between cell growth and siderophore production and chemical characterization of the siderophore type. Its also documents the development of an assay method for the screening of different metals for complexation with siderophores based on the Chrome Azurol S (CAS) assay. The present research aims at batch scale mobilization of arsenic from arsenic contaminated soils using siderophore produced by P. azotoformans and thus evaluating its efficiency as compared to Ethylene Diamine Tetra Acetic Acid (EDTA), Citric Acid (CA) for the same. FT-IR spectroscopic studies were carried out to determine the interaction between soil, arsenic and siderophore. Results have shown that the cell growth and siderophore production are inversely related. Characterization of siderophore produced by P. azotoformans has revealed that it is of mixed-type catecholate and hydroxamate. Siderophore was found to complex with heavy metals like Cadmium, Lead, Nickel, Arsenic (III, V), Aluminium, Magnesium Zinc, Copper, Cobalt, Strontium other than Iron. Five washings by siderophore, EDTA, CA removed almost 92.8%, 77.3%, 70.0% arsenic respectively as compared to only 33.8% removal by control. Washing of arsenic contaminated soil with tap water revealed that ≈ 65.8% of arsenic in contaminated soil is in freely available or weakly bound form. The IR spectra revealed that hydrogen bonding exists between siderophore, arsenic and soil. Encouraging results of arsenic removal by biomolecule-siderophore can lead to an emerging tool brimming with opportunities for environmental clean up.

Solids and phosphorus found within urban stormwater have the potential to cause environmental damage to ecological systems in receiving waters. The evaluation of these pollutants in urban stormwater is usually undertaken by physico-chemical monitoring programs which sample streamflow for laboratory assessment. In this study, data from two such monitoring programs have been examined for the catchment characteristics which influence solids and phosphorus discharge behaviour and the potential for the use of surrogate indicators to predict streamflow concentrations. The study involved partitioning of the components on the basis of the dissolved and particulate fractions. Investigation of the physical and chemical behaviour of solids and phosphorus by univariate and multivariate data analysis techniques led to the identification of interrelationships among the measured parameters. Thus, using turbidity and conductivity, relationships were developed for suspended and dissolved solids. Similarly, relationships were developed for dissolved and particulate phosphorus using suspended and dissolved solids. These relationships have the potential to enhance rapid generation of vital information from site-based measurements and to reduce the requirements for laboratory-based analysis of indicator concentrations in urban stormwater.