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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.
The physico-chemical parameters of coffee effluent consists of very high amount of BOD (2200 mg dm-3), TDS (1810 mg dm-3), NO3 (26.4 mg dm-3), NH4 + (12.6 mg dm-3), low pH (4.3) and zero DO values. Despite the reduction of these values by dilution effect of river water, BOD values as high as 1900 mg dm-3 and 1700 mg dm-3 were found at the downstream sites of Bore and Fite rivers. For biological assemblage study, 6047 macroinvertebrates representing 27 different taxa were identified from riffle sampling sites. The average Shannon and equitability indices and total EPT taxa were reduced at the downstream sites. The habitat score of the study sites was in the range of 27% (very poor) up to 84% (excellent).
Current Polish Standard methods for the determination of sodium, potassium, magnesium, and calcium in natural fresh water were compared with other official standards, mostly from the U.S. (ASTM, USEPA, USGS), regarding recommended top concentrations of measured elements in measured solutions and methods of regulating the sensitivity of measurements. Some of the disadvantageous limitations of conditions and methods of performing the spectrometric measurements that exist in Polish Standards were shown.
Our study was undertaken to compare the behaviour and properties of two new ketoimine sorbents with a commercial sorbent C-18. The sorbents were used to concentrate the endocrine-disrupting compounds (EDCs) in the water, by the use at solid phase extraction (SPE). EDCs were analyzed by high performance liquid chromatography (HPLC) coupled to UV detection. The residues of bisphenol A, bisphenol A diglycidyl ether, bisphenol F and bisphenol F diglycidyl ether in the water having contact with polycarbonate plastic have been determined. The applicable concentration range was 0.5 to 100 µg/l in water samples. Detection limits were of about 0.20 µg/l for BPA and BPF, and 0.50 µg/l for diglycidyl ether derivatives. The recovery of bisphenol A introduced into water ranged from 93.3% to 97.0%, of BPF from 91.6% to 95.9%, of BADGE from 82.0% to 86.4%, and of BFDGE from 79.7 to 82.5%. The proposed method is simple and sensitive, and thus well suited for analysis of ECDs in the water.
The aim of this study was to optimize of a method for determining of compounds which are responsible for the earthy/musty odour in surface water. Among taste and odour contaminants the following compounds are mentioned: (+/-)-geosmin, 2-methylisoborneol, 2,4,6-trichoroanisole, 2-isopropyl-3-methoxypyrazine and 2-isobutyl-3-methoxypyrazine. Some experiments were performed to examine the extraction conditions such as fiber exposure time, temperature of extraction and salt addition. Various SPME fibers such as PDMS, CAR/PDMS and PDMS/DVB coatings were used for the isolation of tested compounds from water samples. As tested, compounds 2-methylisoborneol, 2-isopropyl-3-methoxypyrazine and 2-isobutyl-3-methoxypyrazine were used. After SPME optimization, real surface water samples were examined using the SPME-GC/MS method. Based on preliminary experiments the qualitative and quantitative analyses for the determination of (+/-)-geosmin, 2-methylisoborneol and 2,4,6-trichloroanisole were performed. The regression coefficients for calibration curves for examined compounds are R²≥0.990. This shows that the used method is linear in the examined concentration range (from 20.32 to 168.00 ng/L). one of the reasons for the formation of taste and odour contaminants can be surface water pollution. The changes of water conditions such as temperature, pH and conductivity were examined. And, for the test of periodical changes of geosmin concentration in surface water samples, the experiments were performed in various seasons.
This paper shows speciation analysis of arsenic, antimony and selenium using hydride generation atomic absorption spectrometry. Determining different forms of given elements (forms on different oxidation stages: As(III)/As(V), Sb(III)/Sb(V), Se(IV)/Se(VI) and forms bound with organic matter) is based on different kinetics of hydride generation for forms on different oxidation degrees. This paper shows steps for speciation analysis as described in literature, the main procedures and reagent used in different studies.
Measurement of Na, K, Mg and Ca concentrations in natural fresh (non-mineralized) water samples can be performed in the same sample solution with little or no dilution, in acetylene-air flame with the addition of lanthanum chloride (La 15 g/L), caesium chloride (Cs 1.0 g/L) and hydrochloric acid (HCl 2.0% V/V) by flame atomic emission (Na, K) and absorption (Mg, Ca) spectrometry. Examined remaining influence of other major elements and main interfering components (i.e. sulphates (VI) and silicon) on measured elements was found to be minimal. The recoveries for various concentrations of individual elements in test solutions that had considerably different concentrations of Na, K, Mg and Ca and various participation of sulphates and silicon as well as different values of mineralization were found to be 98.9÷100.6 %, 99.2÷100.6 %, 99.1÷100.9 % and 99.1÷100.9 % for sodium, potassium, magnesium and calcium, respectively.
The study characterizes specific therapeutic waters in Polish health resorts, which contain iodide, fluoride, silicon, sulphides, iron(II), carbon dioxide and radon in concentrations that ensure the therapeutic status of water and specify how it can be used for medical treatment. Based on the physicochemical analysis, it has been verified that among 160 waters from 39 health resorts, 37 contain Fe(II) in concentrations > 10 mg dm–3, which means that they can be classified as ferruginous. Twelve waters containing fluoride in concentrations > 2 mg dm–3 were recognized as therapeutic fluoride waters. Five waters were classified as siliceous ones owing to the content of silicon compounds above 70 mg dm–3 (H2SiO3). Twenty-eight of the analysed waters contain sulphides (H2S+HS–) in concentrations > 1 mg dm–3 and 64 waters contain iodide in concentrations > 1 mg dm–3. Carbon dioxide, which occurs in 72 waters in concentrations above 1 g dm–3 (acidulous waters), proved to be the most widespread component. Waters which contain radon in an amount corresponding to the radiation of 74 Bq (2 nCi) in 1 dm3 are classified as radon waters. Ten of the analysed waters were found to contain this element. The waters were highly varied in chemical composition and type of specific components. Sulphurous waters are mainly used for mineral baths; ferruginous waters are drunk; fluoride and silicon-rich waters are taken for mineral baths and iodide waters are used for mineral baths and inhalations. Using these waters in balneotherapy is an important part of spa treatment and defines different healing profiles of Polish health resorts.
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.
Oznaczono zawartość fluorków w wodzie pitnej oraz w pastach i pojedynczych próbkach żeli i proszków do czyszczenia zębów.
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