Determination of Phosphorous and Nitrogen in the Sediment of Lake ‘pamvotis’ (Greece)

Abstract

Phosphorous and nitrogen nutrients in the sediment of the lake Pamvotis were determined by standard methods of analysis. The pore water of the sediment was also analyzed for orthophosphate, ammonia and nitrate content. The results give evidence that nutrient phosphorus content of the sediment is increased at the summer periods and with nitrogen content being available during the whole year gives eutrophic behavior in the lake waters. However, the winter rains reduce the phosphorous content during the spring months. The phosphorus is introduced into the lake by agricultural runoffs and by trenches from urban areas. Several isolated events originating from activities of the inhabitants of the small island and the human activities around the lake give rise to temporary pollution of the lake waters.     

Metals in precipitation and lake waters in the North-West of Russia

Standard monitoring data on the concentration of metals in precipitation and lake water in 2000s have been analyzed. All monthly average concentrations of Pb in Cd in precipitation were lower than the corresponding maximum allowable concentrations (MACs), whereas the concentrations of Cu, Zn, and Fe in lake surface waters were similar to or exceeded MACs for fishery reservoirs. The peak concentration of Pb in precipitation in June indicated increased dust content of air in late spring and early summer due to soil exposure and plowing. Increased concentration of Zn in the Kubenskoe Lake surface water in spring is likely to result from the peak discharge of anthropogenic pollutants on melting of snow and ice.     

Spectrophotometric Determination of Phenols and Cyanides After Distillation from Natural Waters

Abstract

Total phenols were determined by molecular spectrophotometry, after distillation, complexation with 4-aminoantipyrine and extraction into chloroform. Cyanides were also determined spectrophotometrically after distillation from the acidified samples, and complexation in moderate acidic solution with barbituric acid. The dynamic ranges were 0 – 100 μg L^?1 for total phenols and 0 – 30 μg L^?1 for cyanides. The above methods were applied in the analysis of river, lake and stream waters collected from Northern Greece. The seasonal and spatial variation of concentrations was evaluated by two-way ANOVA. Background levels (4 – 12 μg L^?1 for total phenols and 0.3 – 3 μg L^?1 for cyanides), were found in almost all surface waters, with some exceptions.     

Determination of praseodymium,neodymium and erbium in hot spring and crater lake waters by neutron activation analysis incorporating the standard addition technique

Previously undetermined three rare earth elements (REE's), Pr, Nd and Er, in acidic hot spring and crater lake waters were determined at ppb levels by neutron actavation analysis with the standard addition technique. Errors on final detemined values were 7.1–56%. Combining the present results and the results previously obtained amounts to the determination of all 14 naturally occuring REE's in the waters.     

Sulphonamide Residues in Italian Surface and Drinking Waters: A Small Scale Reconnaissance

The occurrence of antibiotics in the aquatic environment is an important emerging issue due to potential adverse effect of these compounds on ecosystem and human health. For a correct environmental risk assessment there is a need for appropriate analytical methods for monitoring antibiotic residues in a variety of water matrices. This paper describes a method for the determination of eleven sulphonamide compounds in surface and drinking waters using solid-phase extraction and liquid chromatography-tandem mass spectrometry. Recoveries of the analytes in both surface and drinking water matrices at different fortification levels, always exceed 87%; the limits of quantification in surface water samples are between 0.005 and 0.021 μg L⁻¹ depending on the compound, and the interday method precision is less than 12%. Matrix effects were evaluated in drinking and surface water samples. The method has been applied to a small scale reconnaissance of river, lake, mineral and municipal water samples; results indicate the occurrence of sulphonamides in some surface and mineral waters analyzed.     

Butyltins in california river and lake marina waters

Butyltins were analyzed in waters from California river and lake marinas and were detected at the part per trillion (ppt) level in most locations. The tributyltin:dibutyltin (TBT/DBT) ratios in the fresh waters were similar to those in their saline counterparts indicating like rates of degradation in the two salinity regimes.     

A chemometric approach to the investigation of major and minor ion chemistry in Lake Como (Lombardia, Northern Italy

A chemometric approach based on Principal Component Analysis (PCA) has been proposed, in order to study chemical features (major and minor ions, total alkalinity, dissolved silica) of surface and deep waters of Lake Como (Northern Italy). The method allowed us to investigate the correlations between the analyzed ions in an easy-to-see way, using bi-dimensional graphs. In wintertime, the ionic composition of Lake Como waters seems to be mainly related to the geological composition of the lake basin, with a crystalline bedrock on the northern side and a sedimentary cover in the southern part. The presence of contaminants such as bromide and nitrite in water columns is also evidenced and discussed.     

Preliminary fingerprinting of Athabasca oil sands polar organics in environmental samples using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

There is a growing need to develop analytical methods that can distinguish compounds found within industrially derived oil sands process water (OSPW) from those derived from natural weathering of oil sands deposits. This is a difficult challenge as possible leakage beyond tailings pond containments will probably be in the form of mixtures of water-soluble organics that may be similar to those leaching naturally into aquatic environments. We have evaluated the potential of negative ion electrospray ionization high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) for comparing oil sands polar organics from tailing ponds, interceptor wells, groundwater, river and lake surface waters. Principal component analysis was performed for all species observed. which included the O(2) class (often assumed to be monocarbxoylic naphthenic acids) along with a wide range of other species including humic substances in the river and lake samples: O(n) where n=1-16; NO(n) and N(2)O(n) where n=1-13; and O(n)S and O(n)S(2) where n=1-10 and 1-8, respectively. A broad range of species was investigated because classical naphthenic acids can be a small fraction of the 'organics' detected in the polar fraction of OSPW, river water and groundwater. Aquatic toxicity and environmental chemistry are attributed to the total organics (not only the classical naphthenic acids). The distributions of the oil sands polar organics, particularly the sulfur-containing species, O(n)S and O(n)S(2), may have potential for distinguishing sources of OSPW. The ratios of species containing O(n) along with nitrogen-containing species: NO(n), and N(2)O(n), were useful for differentiating organic components derived from OSPW from those found in river and lake waters. Further application of the FTICRMS technique for a diverse range of OSPW of varying ages and composition, as well as the surrounding groundwater wells, may be critical in assessing whether leakage from industrial sources to natural waters is occurring.     

238U and 222Rn activity concentrations and total radioactivity levels in lake waters

The concentrations and distributions of natural radioactivity, uranium and radon in lake waters from around Van, Turkey were investigated with an aim of evaluating the environmental radioactivity. Fourteen lake waters were collected from different six lakes around Van (Turkey) to determine ²³⁸U, ²²²Rn and total alpha and total beta distributions in 2009. The total α and total β activities were counted by using α/β counter of the multi-detector low background system (PIC-MPC-9604) and the ²³⁸U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2) and radon concentrations were measured with the solid state nuclear track detector technique. The activity concentrations ranging from ND to 0.039 Bq L^?1 and from 0.026 to 3.728 Bq L^?1 for total alpha and beta, respectively, and uranium concentrations ranging from 0.083 to 3.078 μg L^?1, and radon concentrations varying between 47.80 and 354.86 Bq m^?3 were observed in the lake waters.     

Determination of trace vanadium in natural waters by a combined ion exchange—catalytic photometric method

A sensitive, selective and simple method is described for the determination of trace vanadium in natural waters. Vanadium is separated and concentrated by a combined cation- and anion-exchange procedure in 0.05 M HCl—0.1 % H₂O₂ media, and determined by the catalytic method based on the oxidation of gallic acid by bromate. The proposed method is applied to the analysis of natural waters. The relative standard deviations are 3.9 % for 0.8 p.p.b. of vanadium in river water and 3.2 % for 1.9 p.p.b. of vanadium in lake water (surface). As little as 0.03 p.p.b. of vanadium can be determined in samples of 100 ml or less.     

Concentrations of arsenic in brackish lake water: application of tristimulus colorimetric determination.

The evaluation of a simple and rapid tristimulus colorimetric method for the determination of arsenic in brackish waters and its application to brackish water samples taken from brackish Lake Nakaumi are described. The determinations of arsenic in brackish water samples were made satisfactorily independent of sample salinity. By applying this method to lake water samples, the distributions and behaviors of arsenic in the lake and their controlling factors were clarified, such as seasonal variations of arsenic and the effect of a typhoon.     

Validation of an SPME method,using PDMS,PA, PDMS-DVB,and CW-DVB SPME fiber coatings,for analysis of organophosphorus insecticides in natural waters

Solid-phase microextraction (SPME) has been optimized and applied to the determination of the organophosphorus insecticides diazinon, dichlofenthion, parathion methyl, malathion, fenitrothion, fenthion, parathion ethyl, bromophos methyl, bromophos ethyl, and ethion in natural waters. Four types of SPME fiber coated with different stationary phases (PDMS, PA, PDMS-DVB, and CW-DVB) were used to examine their extraction efficiencies for the compounds tested. Conditions that might affect the SPME procedure, such as extraction time and salt content, were investigated to determine the analytical performance of these fiber coatings for organophosphorus insecticides. The optimized procedure was applied to natural waters - tap, sea, river, and lake water - spiked in the concentration range 0.5 to 50 micro g L(-1) to obtain the analytical characteristics. Recoveries were relatively high - >80% for all types of aqueous sample matrix - and the calibration plots were reproducible and linear (R(2)>0.982) for all analytes with all the fibers tested. The limits of detection ranged from 2 to 90 ng L(-1), depending on the detector and the compound investigated, with relative standard deviations in the range 3-15% at all the concentration levels tested. The SPME partition coefficients (K(f)) of the organophosphorus insecticides were calculated experimentally for all the polymer coatings. The effect of organic matter such as humic acids on extraction efficiency was also studied. The analytical performance of the SPME procedure using all the fibers in the tested natural waters proved effective for the compounds.     

Molecular dynamics study on the microscopic details of the evaporation of water

Molecular dynamics simulations were conducted on a drop of water (containing 4890 TIP3P waters) at 350 K. About 70 evaporation events were found and characterized in enough detail to determine significant patterns relating to the mechanism of evaporation. It was found that in almost all evaporation events that a single, high-energy state immediately preceded the evaporation event. In ～50% of the cases, this high-energy state involved a short oxygen-oxygen distance, suggesting a van der Waals collision, whereas in the remaining cases, a short hydrogen-hydrogen distance was found, suggesting an electrostatic "collision". Of the high-energy states that led to evaporation, about half occurred when the coordination number of water was 1, and about half, when the coordination number was 2. It was found that the 1-coordinated waters (～1% of the surface waters) and 2-coordinated waters (6% of the surface waters) were responsible for almost all the evaporation events.     

TRACE METALS IN VANDA LAKE IN ANTARCTICA——A VERTICAL MIGRATION MODEL OF TRACE METALS IN CLOSED BASIN

Vanda Lake, a typical dimictic CaCl_2 type salt lake, is located in the Wright Valley inAntarctica. Based on the chemical and physical features of the salt lake water, the authorsdiscussed the vertical geochemical distribution of Fe, Mn, Pb, Cr, Cu, Co, Ni, Cd in the lake,and their vertical migration in lake waters, and have tried to set up a model of vertical mi-gration of these trace elements in the water of a closed chloride type salt lake.     

Field testing of lake water chemistry with a portable and an AUV-based mass spectrometer

Two mass spectrometers (MS) are tested for the measurement of volatile substances, such as hydrocarbons and metabolic gases, in natural waters. KOALA is a backpackable MS operated from above the water surface, in which samples are pumped through a flow cell using a syringe. NEREUS is an underwater instrument hosted by an autonomous underwater vehicle (AUV) that is linked to a communications network to provide chemical data in real time. The mass analyzers of the two MS are nearly identical cycloids, and both use flat-plate membrane inlets. Testing took place in an eutrophic, thermally stratified lake exhibiting steep chemical gradients and significant levels of methane. KOALA provided rapid multispecies analysis of dissolved gases, with a detection limit for methane of 0.1 ppm (readily extendable to 0.01 ppm) and savings of time of at least a factor of 10 compared to that of conventional analysis. The AUV-mounted NEREUS additionally provided rapid spatial coverage and the capability of performing chemical surveys autonomously. Tests demonstrated the need for temperature control of a membrane inlet when steep thermal gradients are present in a water body, as well as the benefits of co-locating all sensors on the AUV to avoid interference from chemically different waters entering and draining from the free-flooding outer hull. The ability to measure dissolved volatiles provided by MS offers potential for complementarity with ionic sensors in the study of natural waters, such as in the case of the carbonate system.     

Releases of radium from an abandoned uranium mine site: Žirovski Vrh uranium mine, Slovenia

Since the beginning of explorative uranium mining at the Žirovski Vrh uranium ore deposit area in 1968, a radioactivity monitoring programme has been carried out. The extent of the programme has varied according to the pre-operational, operational, and, finally, post-operational conditions. In this paper, our ten year results on the dissolved radium concentrations in surface waters, which have been contaminated and potentially affected by the uranium mining and milling activities, are reported. With the exception of waters drained from the hydrometallurgic waste site with radium content ranging from 2 to 9 kBqm⁻³, radium content is far below the drinking water limit of 1000 Bqm⁻³; in the Brebovŝčica stream, which collects all the waters affected by the mine, the present radium concentration does not exceed 10 Bqm⁻³.     

Seasonal and water column trends of the relative role of nitrate and nitrite as *OH sources in surface waters

Based on literature data of sunlight spectrum, photolysis quantum yields, and absorption spectra, the relative role of nitrite and nitrate as *OH sources in surface waters was assessed, and its dependence on the season and the depth of the water column studied. In the majority of surface water samples (river, lake and seawater) nitrite is expected to play a more important role as *OH source compared to nitrate, in spite of the usually lower [NO2(-)] values. Interestingly, under the hypothesis of a constant ratio of the concentrations of nitrate and nitrite (to be corrected later on for the actual concentration ratio in a given sample), the relative role of nitrite compared to nitrate would be minimum in summer, at noon, in the surface layer of natural waters. Any decrease in the sunlight intensity that can be experienced in the natural environment (different season than summer, water column absorption, time of the day other than the solar noon), with its associated influence on the sunlight spectrum, would increase the relative role of nitrite compared to nitrate.     

Chemometrical Interpretation of Lake Waters after their Chemical Analysis by Using Aas,Flame Photometry and Titrimetric Techniques

This article reports the distribution of trace metals and major ions in lake waters of Sultansazl L < L , a reedfield near Kayseri, Turkey. The determination of elements such as Cr, Ni, Cu, Cd and Pb in lake water samples was performed by AAS after a preconcentration step using a column packed with Amberlite XAD-16 resin. Both flame- and graphite furnace-atomic absorption spectrometry was used to determine these metals in lake water samples. The concentrations of the metals bound to humic substances, and free metal ions were determined after their sorption-elution on the resin, separately. The column method optimized with sodium tetraborate reagent was used in determining the free metal ions. In the determinations of Ca²⁺ and Mg²⁺, K⁺ , and SO2-4 , Cl ^m and total hardness, flame atomic absorption spectrometry, flame photometry, and titrimetry were used, respectively. In order to evaluate the analytical data by multivariate statistical techniques which enable feature reduction and grouping of the pollutant sources in lake waters from their chemical composition, principal component analysis (PCA), cluster analysis (CA) and correlation analysis were used. As a consequence of multivariate statistical evaluation, main anthropogenic sources like traffic, industry and agricultural processes were drawn to be responsible from the pollution in the environment investigated.     

Extraction-Coulometric Determination of Copper as Copper(II) 8-Hydroxyquinolinate

Conditions were selected for the coulometric determination of copper(II) by titrating copper(II) 8-hydroxyquinolinate extracted to chloroform with electrochemically generated bromine. The procedure was tested on model solutions and samples of surface waters. The detection limit is 5 × 10^–7 M at a generation current and time of 1 × 10^–3 A and 10 s, respectively.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 5, 2005, pp. 504–506.Original Russian Text Copyright © 2005 by Shlyamina, Morozova, Anisimova, Budnikov.