Chemical characteristics of aerosols and trace gas distribution over North and Central India

A field campaign on aerosol chemical properties and trace gases measurements was carried out along the Delhi-Hyderabad-Delhi road corridor (spanning about 3,200 km) in India, during February 1-29, 2004. Aerosol particles were collected on quartz and cellulose filters using high volume (PM(10)) sampler at various locations along the route (i.e., urban, semi-urban, rural, and forest areas) and have been characterized for major cations (Na(+), Ca(2+), Mg(2+), K(+), and NH (4) (+)), anions (Cl(-), NO (3)(-), and SO (4)(2-)), and heavy metals (Cu, Cd, Fe, Zn, Mn, and Pb). Simultaneously, we measured NO(2) and SO(2) gases. These species show large spatial and temporal variations. The ambient PM(10) concentration has been observed to be the highest (55 ± 4 μg m(-3)) near semi-urban areas followed by forest areas (48 ± 2 μg m(-3)) and in rural areas (44 ± 22 μg m(-3)). The concentrations of NO( x ) (NO(2)+NO) and SO(2) ranged from 16 to 69 μg m(-3) and 4 to 11 μg m(-3), respectively. Among anions, NO(3)(-) and SO(4) (2-) are the major constituents of PM(10). The urban and semi-urban sites showed enhanced concentrations of Fe, Zn, Mn, Cd, and Pb. This study provide information about atmospheric concentrations of various species in the northern to central India, which may be important for policy makers to better understand the air quality of the region.     

Groundwater quality assessment in the village of Lutfullapur Nawada, Loni, District Ghaziabad, Uttar Pradesh, India

The groundwater quality for drinking, domestic and irrigation in the village Lutfullapur Nawada, Loni, district Ghaziabad, U.P., India, has been assessed. Groundwater samples were collected, processed and analyzed for temperature, pH, conductivity, salinity, total alkalinity, carbonate alkalinity, bicarbonate alkalinity, total hardness, calcium hardness, magnesium hardness, total solids, total dissolved solids, total suspended solids, nitrate-nitrogen, chloride, fluoride, sulfate, phosphate, silica, sodium, potassium, calcium, magnesium, total chromium, cadmium, copper, iron, nickel, lead and zinc. A number of groundwater samples showed levels of electrical conductivity (EC), alkalinity, chloride, calcium, sodium, potassium and iron exceeding their permissible limits. Except iron, the other metals (Cr, Cd, Cu, Ni, Pb, and Zn) were analyzed below the permissible limits. The correlation matrices for 28 variables were performed. EC, salinity, TS and TDS had significant positive correlations among themselves and also with NO (3) (-) , Cl(-), alkalinity, Na(+), K(+), and Ca(2+). Fluoride was not significantly correlated with any of the parameters. NO (3) (-) was significantly positively correlated with Cl(-), alkalinity, Na(+), K(+) and Ca(2+). Chloride also correlated significantly with alkalinity, Na(+), K(+) and Ca(2+). Sodium showed a strong and positive correlation with K(+) and Ca(2+). pH was negatively correlated with most of the physicochemical parameters. This groundwater is classified as a normal sulfate and chloride type. Base-exchange indices classified 73% of the groundwater sources as the Na(+)-SO (4) (2-) type. The meteoric genesis indices demonstrated that 67% of groundwater sources belong to a deep meteoric water percolation type. Hydrochemical groundwater evaluations revealed that most of the groundwaters belong to the Na(+)-K(+)-Cl(-)-SO (4) (2-) type followed by Na(+)-K(+)-HCO (3) (-) type. Salinity, chlorinity and SAR indices indicated that majority of groundwater samples can be considered suitable for irrigation purposes.     

Bacterial community composition of sediments from Artificial Lake Maslak, Istanbul, Turkey

Small artificial lakes are ubiquitous in various natural environments. Small impoundments increase the residence time of water, thereby increasing the potential for retention of nutrients through biological and physical processes. We examined bacterial community structure of Lake Maslak, a small freshwater impoundment located in a densely populated region. The objective of our study was to investigate bacterial communities of the lake sediment which has not been determined and to elucidate the factors controlling bacterial diversity and the biogeochemical processes within the lake. For these purposes, surface water, lake bed sediments, and one core sample were collected. Microbiological characteristic of the lake bed and core sediments was determined by denaturing gradient gel electrophoresis targeting the 16S rRNA gene. Along with the microbiological studies, physicochemical (O(2), pH, temperature) and geochemical properties of the surface (NO (3) (-) , NO (2) (-) , NH (4) (+) ,PO (4) (-) ,SO (4) (2-) , K(+), Mg(2+), Ca(2+)) and pore water (K(+), Mg(2+), Ca(2+)) were determined in addition to heavy metals contents (Co Cu, Fe, Zn, Pb, Cd). Eight lake bed and one core sediments were also collected and analyzed for heavy metals and elemental compositions. Nitrate concentration in the surface water ranges from 0.27-1.8 mg/L, and ammonium (0.0-0.83 mg/L) appears to follow nitrate concentration. Sulfate concentration in the surface water (mean 60 mg/L) is greater than those measured in the pore water (mean, 37.5 mg/L). Fe, Zn, Pb, and Cd were not determined in the surface water, whereas Co was significantly higher both in the surface and pore water. Unlike Co, Pb, Zn, and Cd were not measured in the pore water. Lakebed and core sediments show significant enrichment in Pb, Zn, and Cu, indicating anthropogenic pollution. Consistent with geochemical parameters, microbiological analysis suggests a diverse bacterial community in the lake sediments and influence of anthropogenic pollution (e.g., atmospheric emission) on bacterial community.     

Effect of domestic storage tanks on the quality of drinking waters

An investigation covering 12 districts of Baghdad city was conducted over 2 yr to monitor the effect of domestic storage practice on the quality of drinking water. Water storage tanks are widely used in Iraq as an additional water source. Tap and stored waters were tested for their chemical constituents i.e. Ca, Mg, Na, K, Cl, Zn, Fe, Pb, Cd, and total hardness (T.H.). All the tested elements were within the permissible limits. However, statistical analysis showed a significant variation between the different districts for T.H., Cu, Mg and chloride for both tap and stored waters. Seasonal variations have a significant effect on the levels of some elements. The quality of stored water was not affected by storage practice. Zinc, Pb and Fe were the only elements that showed some variation in the stored waters. This was attributed to the effects of corrosion of the tank metal and the migration of metals from the distribution system.     

Statistical approaches for hydrogeochemical characterization of groundwater in West Delhi, India

Parametric statistical approaches, correlations and multiple linear regressions were used to develop models for the interpretation of hydrogeochemical parameters in the Western part of Delhi state, India. The hydrogeochemical parameters indicated that the groundwater quality is not safe for consumption. The water is moderately saline and the salinity level is increasing over time. There is also the problem of nitrate pollution. The correlation between electrical conductivity (EC) and other water quality parameters except potassium (K(+)), nitrate (NO(3)(-)) and bicarbonate (HCO(3)(-)) is significantly positive and Ca(++)+ Mg(++)/Na(+)+ K(+) is significantly negative. In predicting EC, the multiple R(2) values of 0.996 and 0.985 indicate that 99.6% and 98.5% variability in the observed EC could be ascribed to the combined effect of Na(+), HCO(3)(-), Cl(-), SO(4)(--), NO(3)(-) and Ca(++)+ Mg(++) for the year of 2005 and 2006 respectively. Out of 99.6% of the variability in EC in 2005, 51.2% was due to Cl(-) alone, and 8.5%, 12.5%, 6.1%, 14.7% and 6.7% were due to Na(+), HCO(3)(-), SO(4)(--), NO(3)(-) and Ca(++) + Mg(++). Similarly in 2006, out of 98.5% of the variability in EC, 48.5% was due to Cl(-) alone, and 10.4%, 12.7%, 5.3%, 17.2% and 4.4% were due to Na(+), HCO(3)(-), SO(4)(--), NO(3)(-) and Ca(++)+ Mg(++). The analysis shows that a good correlation exists between EC, Cl(-) and SO(4)(--) either individually or in combination with other ions and the multiple regression models can predict EC at 5% level of significance.     

Chemical speciation of inorganic pollutants in river–estuary–sea water systems

Monitoring studies and thermodynamic modeling were used to reveal the changes of inorganic chemical species of some water pollutants (nutrients and trace metals such as Fe, Mn, Zn, Cu, Cd and Pb) inthe river-estuary-sea water system. The case studies were two rivers, Kamchiya and Ropotamo, representing part of the Bulgarian Black Sea water catchment area, and having different flow characteristics. There were no major differences in inorganic chemical species of the two river systems. NO3(-) and NO2(-) chemical species showed no changes along the river-estuary-sea water system. Concerning phosphates six different species were calculated and differences between the three parts of the systems were established. The HPO4(2-) and H2PO4(-) species were found to be dominant in river waters. The H2PO4(-) species quickly decreased at the expense of HPO4(2-) and Ca, Mg and Na phosphate complexes in estuary and seawater. Trace metals showed a great variety of chemical species. Fe(OH)2(+) species prevailed in river waters, and Fe(OH)3(0) species--in sea waters. Me2+ and MeCO3(0) (Me = Cu, Pb) and PbHCO3(+) were dominant in river waters, while Cu(CO3)2(2-) and PbCl(-) species appear also in sea waters. Cd2+ species prevailed in river and estuary waters, and CdCln(2-n) (n = 1-3) species, in seawater. Free Zn2+ species predominated in all systems but downstream their percentage decreased at the expense of Zn phosphates, carbonates,sulfates and chlorides complexes. Only free Mn2+ species were dominant along the systems.     

Assessment of background levels of trace metals in water and soil from a remote region of Himalaya

Selected trace metals were estimated by atomic absorption spectrometry in the water and soil samples collected from the remote region of Himalaya. The soil samples were analysed for soluble and acid extractable fraction of trace metals. In water samples, Ca, Na, Mg and K emerged as dominant contributors, whereas, Ca, Na, K, Mg, Fe and Pb were estimated at comparatively higher levels in the water extract of the soil. In case of acid extract of the soil samples, Ca, K, Fe, Mg, Mn and Na were found at elevated concentrations. Based on mean levels of the metals, following decreasing concentration order was observed in water samples: Ca > Na > Mg > K > Pb > Co > Cu > Zn > Mn > Cr > Fe > Cd > Li, however, in the acid extract of the soil, following order was noted: Ca > K > Fe > Mg > Mn > Na > Pb > Zn > Cr > Li > Cu > Co > Cd. The correlation study revealed appreciably diverse mutual relationships of trace metals in the water and soil samples. The multivariate cluster analyses exhibited divergent apportionment of trace metals in water and soil samples. Among the trace metals, Cd, Pb, Li, Zn, Cr, Cu, Mn and Co exhibited extreme to significant anthropogenic enrichment in the soil samples, while the rest of the metals were mostly contributed by the natural processes.     

Concentrations of asbestos fibers and metals in drinking water caused by natural crocidolite asbestos in the soil from a rural area

Asbestos fibers and metals in drinking water are of significant importance to the field of asbestos toxicology. However, little is known about asbestos fibers and metals in drinking water caused by naturally occurring asbestos. Therefore, concentrations of asbestos fibers and metals in well and surface waters from asbestos and control areas were measured by scanning electron microscopy (SEM), inductively coupled plasma (ICP) optical emission spectrometer, and ICP–mass spectrometry in this study. The results indicated that the mean concentration of asbestos fibers was 42.34 millions of fibers per liter by SEM, which was much higher than the permission exposure level. The main compositions of both asbestos fibers in crocidolite mineral and in drinking water were Na, Mg, Fe, and Si based on energy dispersive X-ray analysis. This revealed that the drinking water has been contaminated by asbestos fibers from crocidolite mineral in soil and rock. Except for Cr, Pb, Zn, and Mn, the mean concentrations of Ni, Na, Mg, K, Fe, Ca, and SiO₂ were much higher in both surface water and well waters from the asbestos area than in well water from the control area. The results of principal component and cluster analyses indicated that the metals in surface and well waters from the asbestos area were significantly influenced by crocidolite mineral in soil and rock. In the asbestos area, the mean concentrations of asbestos fibers and Ni, Na, Mg, K, Fe, Ca, and SiO₂ were higher in surface and well waters, indicating that asbestos fibers and the metals were significantly influenced by crocidolite in soil and rock.     

On-site simultaneous determination of anions and cations in drainage water using a flow injection-capillary electrophoresis system with contactless conductivity detection

Drainage water diverted from a farm pasture, which was heavily loaded with manure, was monitored during a rain event. Concurrent anion and cation determinations at intervals of 10 min could be achieved with a new capillary electrophoresis system employing dual injection at opposite ends of the separation capillary. The flow injection approach enabled automation of the sampling process. Interruption of the separation voltage was not necessary. Contactless conductivity detection with an electrolyte solution optimized for the purpose allowed the facile simultaneous detection of the inorganic ions Cl(-), NO(3)(-), SO(4)(2-), HPO(4)(2-), NO(2)(-), NH(4)(+), K(+), Ca(2+), Na(+) and Mg(2+) and the acquisition of temporal concentration profiles of these species. The detection limits achieved were between 20 and 200 [micro sign]g l(-1) for all ions and the repeatability of peak areas and peak heights was better than 1%. The quantitative results were verified by analysing individual samples later in the laboratory with photometry and ion chromatography and the average deviations were found to be between 4 and 12%. This contribution presents a further step in the development of capillary electrophoresis towards a fully automated, low maintenance field method.     

Water and sediment quality of dry season pools in a dryland river system: the upper Leichhardt River, Queensland, Australia

This article presents the geochemical characteristics and physicochemical properties of water and sediment from twelve semi-permanent, dryland pools in the upper Leichhardt River catchment, north-west Queensland, Australia. The pools were examined to better understand the quality of sediments and temporary waters in a dryland system with a well-established metal contamination problem. Water and sediment sampling was conducted at the beginning of the hydroperiod in May and September 2007. Water samples were analyzed for major solute compositions (Ca, Na, K, Mg, Cl, SO(4), HCO(3)) and water-soluble (operationally defined as the <0.45 μm fraction) metals (Cd, Cu, Pb, Zn). Sediment samples were analyzed for total extractable and bioaccessible metals (As, Cd, Cu, Pb, Zn), elemental composition and grain morphology. At the time of sampling a number of pools contained water and sediment with elevated concentrations, compared to Australian regulatory guidelines, of Cu (maximum: water 28 μg L(-1); sediment 770 mg kg(-1)), Pb (maximum: water 3.4 μg L(-1); sediment 630 mg kg(-1)) and Zn (maximum: water 150 μg L(-1); sediment 780 mg kg(-1)). Concentrations of Cd and As in pools were relatively low and generally within Australian regulatory guideline values. Localized factors, such as the interaction of waters with anthropogenic contaminants from modern and historic mine wastes (i.e. residual smelter and slag materials), exert influence on the quality of pool waters. Although the pools of the upper Leichhardt River catchment are contaminated, they do not appear to be the primary repository of water and sediment associated metals when compared to materials in the remainder channel and floodplain. Nevertheless, a precautionary approach should be adopted to mitigating human exposure to contaminated environments, which might include the installation of appropriate warning signs by local health and environmental authorities.     

Chemical characteristics of groundwater and assessment of groundwater quality in Varaha River Basin, Visakhapatnam District, Andhra Pradesh, India

Study on chemical characteristics of groundwater and impacts of groundwater quality on human health, plant growth, and industrial sector is essential to control and improve the water quality in every part of the country. The area of the Varaha River Basin is chosen for the present study, where the Precambrian Eastern Ghats underlain the Recent sediments. Groundwater quality is of mostly brackish and very hard, caused by the sources of geogenic, anthropogenic, and marine origin. The resulting groundwater is characterized by Na(+)?>?Mg(2+)?>?Ca(2+)?:?[Formula: see text]?>?Cl(-)?>?[Formula: see text], Na(+)?>?Mg(2+)?>?Ca(2+)?:?[Formula: see text]?>?Cl(-)?>?[Formula: see text]?>?[Formula: see text], Na(+)?>?Mg(2+)?>?Ca(2+)?:?[Formula: see text]?>?Cl(-), and Na(+)?>?Mg(2+)?>?Ca(2+)?:?Cl(-)?>?[Formula: see text]?>?[Formula: see text] facies, following the topographical and water flow-path conditions. The genetic geochemical evolution of groundwater ([Formula: see text] and Cl(-)-[Formula: see text] types under major group of [Formula: see text]) and the hydrogeochemical signatures (Na(+)/Cl(-), >1 and [Formula: see text]/Cl(-), <1) indicate that the groundwater is of originally fresh quality, but is subsequently modified to brackish by the influences of anthropogenic and marine sources, which also supported by the statistical analysis. The concentrations of total dissolved solids (TDS), TH, Mg(2+), Na(+), K(+), [Formula: see text], Cl(-), [Formula: see text], and F(-) are above the recommended limits prescribed for drinking water in many locations. The quality of groundwater is of mostly moderate in comparison with the salinity hazard versus sodium hazard, the total salt concentration versus percent sodium, the residual sodium carbonate, and the magnesium hazard, but is of mostly suitable with respect to the permeability index for irrigation. The higher concentrations of TDS, TH, [Formula: see text], Cl(-), and [Formula: see text] in the groundwater cause the undesirable effects of incrustation and corrosion in many locations. Appropriate management measures are, therefore, suggested to improve the groundwater quality.     

Composition, seasonal variation, and sources of PM10 from world heritage site Taj Mahal, Agra

Air samples for PM(10) (dp?相似文献   

Groundwater quality under the influence of spent mushroom substrate weathering

Nitrate and other solutes resulting from field-weathering of spent mushroom substrate (SMS) percolate into underlying soils and may migrate to groundwater. A field trial was conducted to investigate the potential influences of SMS weathering on groundwater quality. Spent mushroom substrate was deposited at 90 and 150 cm pile depths over a Typic Hapludult and weathered for 2 years. Eight casing wells were installed around the SMS piles to monitor the quality changes of groundwater with a high seasonal water table of 760 cm below the surface. Although leachate solutes had moved more than 200 cm deep in soil from the surface, no significant changes of groundwater quality caused by SMS weathering were observed even one year after removal of the SMS piles (3 years total). The groundwater had pH, electrical conductivity (EC) and dissolved organic carbon (DOC) of 4.3-5.7, 0.2-0.3 dS m(-1) and 0.7-2.2 mg L(-1), respectively. The major inorganic ions were Mg(2+), Ca(2+), Na(+), Cl(-), SO(4)(2-) and NO(3)(-), with a concentration range of 2.5-68.3 mg L(-1). The results suggest that SMS leachate solutes migrated fairly slow in deep subsurface soils of the experimental field. Considering that leachate solutes may move several meters in soil through preferential flow channels, weathering of SMS in fields with a high seasonal groundwater table >or=5 m below the ground is recommended. Conservatively, SMS weathering should be conducted on compact surfaces and leachate be collected and reused as liquid fertilizers.     

Chemical dynamics of the Sava riverine system

Presented here is a study of the geochemical dynamics of the entire River Sava watershed, a major tributary of the River Danube which has not previously been investigated. The sampling was performed at 33 selected locations along the main channel of the stream and at its largest tributaries during three sampling seasons (fall 2005, spring 2006 and fall 2006), going from headwater locations to the mouth near the confluence with the Danube. Almost 80% of the solutes are derived from carbonate mineral weathering and represent over 50% of specific HCO(3)(-) flux normalized to unit basin area at the mouth of the Danube. Statistical analysis indicates that agricultural and industrial sources contribute significantly to increased Na(+), K(+), Cl(-), SO(4)(2-) and NO(3)(-) concentrations in tributary waters. Different processes control the water chemistry along the course of the Sava's drainage-the upper reaches are largely regulated by contributions from carbonate mineral weathering, the middle reaches are influenced by agricultural activity and biological processes related to eutrophication, while the lower reaches tend to have more pronounced parameters related to the industrial processing along with leakages from municipal sanitary systems of these higher population density areas.     

Radiochemical characterization of mineral waters in the Eastern Black Sea Region, Turkey

This study has evaluated the levels of natural radionuclides and chemical components of mineral waters in the Eastern Black Sea Region (Turkey). The mean activity concentrations of (226)Ra, (232)Th, (137)Cs, (40)K, gross alpha and gross beta were found as 129, 33, 28, 714, 125 and 170 mBq L(-1), respectively. Due to consumption of mineral waters, the radiological impact of them on the inhabitants was calculated by taking the annual intake into account through ingestion of aforementioned radionuclides. The estimated effective doses from mineral water were found to be 13.20 μSv year(-1) ((226)Ra), 2.74 μSv year(-1) ((232)Th), 0.13 μSv year(-1) ((137)Cs) and 1.62 μSv year(-1) ((40)K). The overall contribution of these radionuclides to the committed effective dose from a year's consumption of mineral water in the region is therefore estimated to be only 17.69%, which is in concordance with the recommended WHO value (100 μSv year(-1)). The chemical analysis results showed that these waters contain Na, Al, P, Cl, K, Ca, V, Mn, Fe, Ni, Cu and Zn elements. These values were evaluated and compared with the internationally verified values. This study provides important information for consumers and authorities because of their internal radiochemical exposure risk from mineral water intake.     

Statistical apportionment and risk assessment of selected metals in sediments from Rawal Lake (Pakistan)

The present study was carried out in order to evaluate the statistical apportionment and risk assessment of selected metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn) in freshly deposited sediments in Rawal Lake, Pakistan. Composite sediment samples were collected, oven-dried, grounded, homogenized, and processed to assess the water-soluble and acid extractable concentrations of the metals in the water extract and acid extract of the sediments using flame atomic absorption spectrophotometer. Statistical methods were used to identify the possible sources of the metals. Sediment quality guidelines and potential acute toxicity were used to evaluate the ecotoxicological sense of selected metals. Non-carcinogenic health risk assessment was also carried out to determine the potential adverse health risks to the inhabitants. Relatively higher concentration was noted for Ca, Fe, Mg, Na, K, Mn, and Sr in the sediment samples. Principal component analysis and cluster analysis revealed anthropogenic contributions of Cd, Pb, Cr, Mn, Fe, and Li in the sediments. Enrichment factors of the metals in sediments showed severe to moderate enrichment of Cd, Pb, Ca, Fe, Li, Mn, and Sr. Geoaccumulation indices and contamination factors evidenced significant contamination by Cd and Pb, although, on the whole, low degree of contamination was noted. The levels of some metals exceeded the sediment quality guidelines, which revealed frequently adverse biological effects to the dwelling biota in the aquatic ecosystem. The sediments were found to be significantly contaminated by Cd, Pb, Cr, Mn, Fe, and Li.     

Spatial distribution of trace metals (Cd, Pb, Hg, Cu, Zn, Fe and Mn) and oligo-elements (Mg, Ca, Na and K) in surface sediments of the Gulf of Tunis (Northern Tunisia)

The purpose of this paper is to evaluate the levels and spatial distribution of trace metals (Cd, Pb, Cu, Hg, Zn, Fe, and Mn), oligo-elements (Mg, Ca, Na and K), total organic carbon (TOC), and total nitrogen (TN) in the fine fraction of surface sediments collected from 38 stations in Gulf of Tunis (Mediterranean Sea, Northern Tunisia) between 2004 and 2005. The results showed that metals, oligo-elements, TOC, and TN concentrations in the sediments of the Gulf of Tunis are generally low compared to those found in other similar coastal marine areas. The spatial distribution of metals showed areas of major accumulation of Pb, Cd, Cu, Fe, and Zn in the central area of the Gulf and near the Mejerda River. The marine currents are influencing factors on metal accumulation in sediments. The principal component analysis applied to our elemental analytical results showed that there is a positive correlation between Fe, Zn, Cu, and Pb. These metals have a stronger affinity with site connection in the sediments than Ca and Mn.     

Atmospheric deposition of major ions and trace metals near an industrial area,Jordan

Al, Cd, Cr, Cu, Fe, Mn, Pb, Zn, NH4+, Mg2+, Ca2+, Na+, K+, Cl-, NO3- and SO4(2-), along with pH were determined in wet and dry deposition samples collected at Al-Hashimya, Jordan. Mean trace metal concentrations were similar or less than those reported for other urban regions worldwide, while concentrations of Ca2+ and SO4(2-) were the highest. The high Ca2+ concentrations were attributed to the calcareous nature of the local soil and to the influence of the Saharan dust, while the high concentrations of SO4(2-) were attributed to the influence of anthropogenic sources and Saharan dust soil. Except for SO4(2-), NO3-, and Ca2+, dry deposition fluxes of measured metals and ions were higher than their corresponding wet deposition fluxes. The high annual average pH values recorded for wet and dry deposition samples were attributed to the neutralization of acidity by alkaline species. Cd, Cr, Cu, Pb, Zn, NO3- and SO4(2-) were enriched in wet and dry deposition samples relative to crustal material, and a significant anthropogenic contribution to these elements and ions is tentatively suggested. Finally, the possible sources and the main factors affecting the concentrations of the measured species are discussed.     

Chemical speciation in natural and brine sea waters

A combined approach consisting of monitoring and thermodynamic modeling was used in order to calculate the concentration of trace element species in water samples of a broad salinity range and to explain their chemical behaviour. The study was performed on water samples (fresh, marine, hyper-saline) taken from the area of Burgas Bay, Bulgaria. The ion association model based on Debye-Hückel theory using the sst2008.dat database and the ion interaction model based on Pitzer theory using a new pit2010.dat database were compared and combined for the purposes of this study. The new pit2010.dat database combines the sst2008.dat database and the pitzer.dat database of the PHREEQCI computer program as well as the thermodynamic data for the elements Fe, Mn, Cu, Zn, Cd and Pb and their Pitzer ion interaction parameters. The results showed that: (1) the predominant species in fresh waters were free ions of Mn(2+) (73.6%), Zn(2+) (58.0%) and Cd(2+) ions (78.3%) as well as carbonate species CuCO?? (81.8%), PbCO?? (77.2%) and hydroxy species Fe(OH) ??(55.2%) and Fe(OH)+?(35.6%); (2) an increase in chloride species MeCl2(n)-(n)(n = 1-4, Me = Mn, Zn, Cu, Pb and Cd) and of the hydroxy species Fe(OH)?? for Fe was calculated for sea and hyper-saline water.     

Onsite direct-read system for semi-quantitative detection of traces of beryllium on surfaces

The present work describes a simple and reproducible direct-read system for onsite monitoring of beryllium on surfaces of work areas. It is based on the colorimetric reaction of beryllium with active ingredients deposited in a swab. A color comparator consisting of beryllium color chart was designed to enable the semi-quantitative determination of beryllium in surface samples. The system provides a minimum detection limit of 0.01 microg sample(-1). Metals tested for any interference effect include Al(3+), Ba(2+), Cd(2+), Cu(2+), Co(2+), Cr(3+), Cr(6+), Fe(3+), Hg(2+), Mg(2+), Ni(2+), Pb(2+), Ti(4+) and UO(2)(2+). Validation of the system showed no significant effect from metal interferences on the quantification of beryllium.