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In the Aroniae fructus, Rubi idaei fructus, Sambuca fructiis, Rosae fructus, Sorbí fruetus, Pyriis malus fructus, Foeniculi fructus, Pruni spinosae fructus and Myrtilli fructus, the contents of Fe3+, Cu2+, Zn2+ and Mn2+ ions were determined by the flame atomic absorption spec­trometry (MS) and ion chromatography (IC). It was found that the quantities of the ex­amined ions differ and vary in the investigated species. The amounts were: Fe3+ 20.99 - 1084.3 mg/kg; Cu2+ 2.44 - 13.58 mg/kg; Zn2+ 8.19 - 139.11 mg/kg and Mn2+ 4.88 - 217.32 mg/kg of dry mass.
Chromium exists usually in the (III) or (VI) oxidation states. In contrast to Cr(III), which is essential to mammalian systems, Cr(VI) is dangerous for humans due to its toxicity and carcinogenic properties. Cr(VI) compounds are highly soluble, mobile and bioavailable compared to Cr(III) species. Chromium is usually analyzed using instrumental methods such as AAS or ICP, which are accurate and sensitive, but allow determination of only the total content of chromium in a sample. Determination of Cr(VI) still represents a formidable challenge in analytical chemistry. This paper describes sensitive and selective determination of Cr(VI) in water samples on μg L-1 levels using an ion chromatography system with UV detector, without any sample preconcentration method. The detection limits achieved were less than 0.1 μg L-1 in deonized water and 0.2 μg L-1 in rainwater and drinking water, respectively. The method was applied to determination of Cr(VI) in rainwater and water extracts from galvanic sediments.
Swimming pool water treatment in general includes flocculation, sand filtration and subsequent disinfection. Chlorite, chlorate and bromate are disinfection by-products of swimming pool water treated by chlorine species or ozone. They are responsible for adverse effects on human health and their analyses in swimming pool water are necessary. The simply and fast suppressed ion chromatography simultaneous separation and conductivity determination of chlorite, chlorate, bromate, fluoride, chloride, nitrate, bromide, phosphate and sulfate in disinfected swimming pool water has been described. The separation was performed on an anion-exchange column with 1.0 mM Na₂CO₃ + 3.2 mM NaHCO₃ as eluent, and determination by suppressed conductivity detection. Chlorite has been found in 5 analyzed samples, chlorate in all of them, and bromate in the 2 samples originated from ozonated swimming pool water. Ions were analyzed in the wide concentrations range from 0.05 mg L⁻¹ (bromate) up to 300 mg L⁻¹ (chloride, sulfate). Linearity of disinfection by-products was checked up to 2.0 mg/L (chlorite), 30 mg L⁻¹ (chlorate) and 0.5 mg L⁻¹ (bromate) with a 50 μL injection loop (r²= 0.9966 – 0.9985), respectively. Fluoride, chloride, nitrate, bromide, phosphate, and sulfate did not interfere with target anions. The detection limits of ClO₂⁻, ClO₃⁻ and BrO₃⁻ were on the levels: 0.19 mg L⁻¹, 0.69 mg L⁻¹ and 0.006 mg L⁻¹, respectively. The mean recoveries of target anions for spiked samples were 85% – 110% and coefficient of variation of analyzed anions do not exceed 4.72%. The concentrations of inorganic disinfection by-products differ from 0.31 mg L⁻¹ up to 31.92 mg L⁻¹.
One possible method of drinking water treatment is chlorine dioxide disinfection. This technology, however, requires reliable control of its byproducts, including chlorite ions., which pose a threat to human health. In this paper an original procedure for flow indirect determination of chlorite in drinking water was described. This method relies on oxidization of chlorite ions by iron(III) in acid environment measurement of the spectrophotometric signal for the phenanthroline/iron(II) complex. The determinations were carried out by flow analysis with the use of a dedicated set of flow instruments. The method was used for analysis of natural samples collected from various water intakes in Kraków. The new analytic approach was compared with the routinely applied ion chromatography method.
Isotachophoresis using coupled capillaries (ITP) and ion chromatography (IC) – two analytical procedures for the determination of anions in atmospheric wet deposition – were compared. Both techniques were used for the determination of anions in small volume samples of dew, rime and fog deposition. IC was characterized by lower limits of detection and quantitation. The wide dynamic range of the technique made it suitable for accurate and precise determination of the analytes in samples of widely different matrices and analyte levels. No significant differences were observed between the two techniques in terms of time- and labor intensity.
The necessity of environmental protection has stimulated development of all kinds of methods allowing determination of different pollutants in different elements of the natural environment, including methods for determining inorganic nitrogen ions. Many of the methods used so far have proven insufficiently sensitive, selective or accurate and recently much attention has been paid to ion chromatography, which seems most promising. This paper reviews applications of ion chromatography for determining nitrate, nitrite and ammonium ions in environmental samples and in food products along with ISO standards and the relevant methods proposed by the US EPA and Dionex. Literature examples describe the application of ion chromatography for determining NO3 ⁻, NO2 ⁻ and NH4 ⁺ ions in water, waste water, air, food products and other complex matrix samples. Critical analysis of the methods based on ion chromatography is presented.
Disinfection of drinking water is usually carried out by chlorination. This is a well-known and effec­tive technology which has many advantages. However, during this process dangerous by-products such as trihalomethanes, as well as chlorate and chlorite are formed. The disinfection of bromide-containing source waters with ozone results in the production of bromate ions (BrO3-), which are formed as a result of a series of complex reactions between ozone and bromide ions present in water. Bromates are possible human carcinogens. For these reasons trace analysis of bromate and other oxyhalides by-products in waters has received considerable attention in recent years. This article describes the determination of bromate in drinking water by IC with post column derivatisa­tion using NaBr/NaNO2 and UV detection. The direct method allows the determination of bromate at low ^g/dm3 levels and sample pretreatment is not necessary.
Many drinking water utilities are changing their primary disinfectant from chlorine to alternative disinfectants such as ozone, chlorine dioxide and chloramines, which reduce regulated trihalomethanes and some organochlorine compounds levels, but often increase levels of others potentially toxicologically important compounds. The hazardous inorganic oxyhalide by-products are bromate, chlorite and chlorate, some of which have been classified as probable human carcinogens. The most important of these is bromate, formed when source waters containing bromide are ozonated. Chlorite is formed when chlorine dioxide is used, whereas chlorate is formed when chlorine, chlorine dioxide, hypochlorite acid or chloramine is used to disinfect drinking water. This paper is a review of ion chromatographic separations of these inorganic oxyhalide disinfection byproducts in drinking water and their detection using conductivity, UV/Vis or mass spectrometry detection. The critical comparison of ISO, US EPA and other methods including limits of detection, availability and costs of analyses is given. Furthermore, a review of papers concerning ion chromatography determination of inorganic oxyhalides in drinking water published during the last 20 years is presented.
The fingerprinting concept that treats a chromatogram as a unique signal without peak identifying has been used in chromatographic comparative analysis. So far, no such approaches of ion chromatography have been published. Therefore, the aim of our work was to perform ion chromatographic analysis of five metals: Fe(III), Cu(II), Ni(II), Zn(II), and Mn(II) in 30 bottled mineral and spring waters available in the Polish market. The fingerprinting approach performed well and its main advantage is no need to perform the calibration procedure of each chromatographed ion. By investiging loadings, intercorrelated and orthogonal peaks were identified. We discuss the chemometric steps needed before comparison: smoothing, baseline removal, and warping.
Background. Legislation for environmentally protecting surface waters in Poland and the EU is considered a priority because of the large human impact on this environmental feature in both highly industrialised countries as well as those that are agriculturally well developed. The biggest threats are regarded as being sewage arising from economic, industrial and agricultural pollution along with rain water run-off from fields treated with fertilizers. One of the most characteristic indicators of pollution exposure in surface waters are inorganic anions which form the principal components of town sewage and fertilizers. Objectives. The estimate the effect that six selected sites of human settlement have on variously sized watercourses running through. The human environmental impact was based on determination of chlorides, nitrates and sulphates concentrations in such waters. Materials and Methods. Water samples were obtained from the following rivers and towns, respectively; the Nil in Kolbuszowa, the Mleczka in Przeworsk, the San in Jaroslaw, the Wislok in Rzeszow, the Bystrzyca in Olimpow and an unnamed watercourse in Niwiska. Sampling sites were chosen at 4-6 points along each watercourse for a given locality. Analyte levels were measured by ion chromatography using the Dionex ICS 1000 instrument. Results. Mean chlorides concentrations were found to vary from 8.52 (±0.17, n=3) mg/L to 78.41 (±0.19, n=3) mg/L, mean nitrates were 6.76 (±0.00, n=3) mg/L to 23.97 (±1.50, n=3) mg/L and mean sulphates from 29.89 (±1.57, n=3) mg/L to 62.48 (±2.99, n=3) mg/L. The clearest environmental effect of settlements on watercourses were observed for the small to medium sized towns of Kolbuszowa, Przeworsk and Jaroslaw in the form of frequently elevated chlorides levels from sewage. Conclusions. By designating various sampling locations, along the watercourses for measuring the human environmental impact of nearby settlements, it is possible to identify sources of river pollution and thus take appropriate remedial action, as and when required.
The paper presents the analytical procedure of organic acids quantification in compound feed by ion chromatography method. Organic acids: acetic, propionic, formic, malic, fumaric, and citric were extracted from a feed sample with water for 30 min. The measurement was done by conductometric detection. The limit of quantification of the assayed acids in the feeds was as follows: acetic 0.50 g/kg, propionic 0.63 g/kg, formic 0.45 g/kg, malic 0.45 g/kg, fumaric 0.50 g/kg, and citric 0.45 g/kg. The coefficient of variation ranged from 0.40% to 1.68% and its mean value was 0.82%. Mean Horrat ratio amounted to 0.35, thus confirming very good precision of the method. The recovery rate of the acids added to the compound feed ranged from 97.2% to 102.5%, with the average of 99.4%.
W pracy przedstawiono metodykę stosowaną w monitoringu zanieczyszczeń powietrza w Puszczy Białowieskiej, gdzie zlokalizowana jest sieć 7 punktów pomiarowych, w których mierzone jest stężenie w powietrzu zanieczyszczeń gazowych (depozycja sucha) i skład chemiczny opadów atmosferycznych (depozycja mokra). Pomiary wykonywane są według jednolitej metodyki stosowanej w europejskim i krajowym monitoringu lasu. Opisano metodę pasywną pomiaru zanieczyszczeń gazowych oraz metody badań opadów atmosferycznych, w tym metodę chromatografii jonowej (IC) oraz optycznej spektrometrii emisyjnej z plazmą wzbudzoną indukcyjnie (ICP-OES). Przedstawiono ocenę poziomu i trendów zmian oraz rozkładu przestrzennego depozycji całkowitej siarki i azotu na obszarze Puszczy Białowieskiej w latach 2002-2010.
The composition and contents of the selected macro- and microelements present in the soil and different organs of two varieties of dittany (Dictamnus albus L.), white (cv. Albiflorus) and purple (cv. Purpureus) were determined. On average, the purple variety contained higher contents of iron, manganese, zinc and copper, whereas the higher contents of nickel and cadmium were found in the white variety.
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