Human exposure to silver released from silver-modified activated carbon applied in the new type of jug filter systems.

BACKGROUND: A water filtered by jug filter system (JFS) can be applied for the preparation of food products, as well as it can be directly consumed as drinking water. In the European Union, in both above-mentioned cases the quality of water filtered using JFSs has to fulfill the requirements listed in Directive 98/83/EC. However, Directive 98/83/EC sets no parametric value for silver, JFSs are not regulated under this legislative act and additionally, silver-modified activated carbon (applied in such systems) has not been approved by European Food Safety Authority (EFSA). Therefore, the exposure to this metal should be assessed for all JFSs containing filtration cartridges with silver-modified activated carbon, present on the retail market. OBJECTIVE: A comprehensive study was conducted in order to examine the effect ofJFSs (consisted of filtration oval-cartridges of the new type with silver-modified activated carbon) on the quality of filtered water regarding the released amounts of silver. Silver migration from such type of cartridges has not been examined before. The aim of work was the assessment of exposure to silver released into filtered water from silver-modified activated carbon applied in such types of FSs. MATERIAL AND METHODS: Silver migration from six brands of JFSs (A-F) was investigated according to British Standard BS 8427:2004 using a validated inductively coupled plasma mass spectrometry method. RESULTS: . The average daily silver concentrations in the composite samples collected on six measurement days forA, B, C, D, E and F JFSs were in the ranges of: 3.95-18.1 microg/l, 4.6-21.7 microg/l, 0.41-8.7 microLg/l, 6.9-10.9 microg/l, 3.3-17.1 microg/1 and 10.1-20.8 pg/1l, respectively. The established grand mean concentrations of released silver from all six oval cartridges were in the range of 2.7-14.3 jg/1. The estimated Hazard Quotient (HQ) indices were in the range of 0.015-0.082 CONCLUSIONS:. The estimated HQ indices were significantly lower than 1 and therefore no long-term risk for human health could be expected. All the investigated JFSs of the new type meet previously established provisional migration limit for silver from such systems--25 microg/L.

Determination of barium in natural waters by ICP-OES technique. Part II: Assessment of human exposure to barium in bottled mineral and spring waters produced in Poland.

BACKGROUND: A method of the classification of natural mineral and spring waters and maximum admissible concentration (MAC) levels of metals present in such types of waters are regulated by Commission Directive 2003/40/EC, Directive 2009/54/EC of the European Parliament and of the Council and Ordinance of Minister of Health of 30 March 2011 on the natural mineral waters, spring waters and potable waters. MAC of barium in natural mineral and spring waters was set at 1.0 mg/l, while World Health Organization determined the Ba guideline value in water intended for human consumption at the level of 0.7 mg/l. OBJECTIVE: The aims of the study were: the determination of barium in natural mineral and spring waters (carbonated, non-carbonated and medium-carbonated waters) produced and bottled on the area of Poland, and assessment of human exposure to this metal presents in the above-mentioned types of waters. MATERIAL AND METHOD: The study concerning barium determinations in 23 types of bottled natural mineral waters and 15 types of bottled spring waters (bought in Polish retail outlets) was conducted in 2010. The analyses were performed by validated method of determination of barium in water based on inductively coupled plasma optical emission spectrometry, using modern internal quality control scheme. RESULTS: Concentrations of barium determined in natural mineral and spring waters were in the ranges from 0.0136 mg/l to 1.12 mg/l and from 0.0044 mg/l to 0.43 mg/l, respectively. Only in the single case of natural mineral water the concentration of barium (1.12 mg/l), exceeded above-mentioned MAC for this metal, which is obligatory in Poland and the European Union - 1.0 mg/l. The long-term monitoring of barium concentration in another natural mineral water (2006 - 2010), in which incidental exceeding MAC was observed in 2006, was conducted. All measured barium concentrations in this water were lower than 1.0 mg/l and therefore, it is possible to state that the proper method of mixing waters taken from six independent groundwater intakes applied during production is actually used. The estimated Hazard Quotient indices were in the ranges: 0.0019 - 0.16 (natural mineral waters) and 0.00063 - 0.061 (natural spring waters), respectively. CONCLUSIONS: The natural mineral waters are usually characterized by higher Ba concentrations than those observed in the cases of natural spring waters. The presence of a high concentration of HCO3- in such types of natural waters ensures the existence of Ba2+ in solution as Ba(HCO3)2, which is a highly soluble salt. Taking into account the concentrations of barium determined in above-mentioned waters and the available toxicological data for this metal no long-term risk for human health could be expected (estimated Hazard Quotient indices < or = 0.16).

[Determination of barium in natural curative waters by ICP-OES technique. Part I. Waters taken on the area of health resorts in Poland]. / Oznaczanie baru w naturalnych wodach leczniczych technika ICP-OES. Czesc I. Wody ujmowane na terenach uzdrowisk w Polsce.

Maximum admissible concentration level (MACL) of barium in natural mineral waters, natural spring waters and potable waters was set at the level of 1 mg/l, while MACL of this element in natural curative waters intended for drinking therapies and inhalations were set at the levels of 1.0 mg/l and 10.0 mg/l, respectively. Those requirements were related to therapies which are applied longer than one month. Above mentioned maximum admissible concentration levels of barium in consumed waters were established after taking into account actual criteria of World Health Organization which determined the guidelines value for this element in water intended for human consumption at the level of 0.7 mg/l. In this work developed and validated method of determination of barium by inductively coupled plasma emission spectrometry technique was applied for determination of this element in 45 natural curative waters sampled from 24 spa districts situated on the area of Poland. Concentrations of barium determined were in the range from 0.0036 mg/l to 24.0 mg/l. Natural curative waters characterized by concentrations of barium in the ranges of 0.0036 - 0.073 mg/l, 0.0036 - 1.31 mg/l and 0.0036 - 24.0 mg/l, were applied to drinking therapy, inhalations and balneotherapy, respectively (some of waters analyzed were simultaneously applied to drinking therapy, inhalations and balneotherapy). In the cases of 11 natural curative waters exceeding limit of 1 mg/l were observed, however they were classified mainly as waters applied to balneotherapy and in two cases to inhalation therapies (concentrations of barium - 1.08 mg/l and 1.31 mg/l). The procedure of classification of curative waters for adequate therapies based among other things on barium concentrations meets requirements of the Decree of Minister of Health from 13 April 2006 on the range of studies indispensable for establishing medicinal properties of natural curative materials and curative properties of climate, criteria of their assessment and a specimen of certificate confirmed those properties.

[Assessment of human health exposure connected with consumption of water characterized with elevated concentration level of silver released from jug water filter systems]. / Ocena narazenia zdrowia ludzkiego zwiazanego ze spozywaniem wody o podwyzszonym poziomie stezenia srebra wymywanego z systemów filtrów dzbankowych.

Silver usually exists in tap water at concentrations which are not connected with human health risk and therefore maximum admissible concentration level of this element was not established in Directive 98/83/EC concerning quality of water intended for human consumption. Disinfection of water based on generation of silver or silver compounds by electrochemical process could led to the increase of concentration of this metal in disinfected water up to level of 0.050 mg/l or higher although it should be underlined that this type of technology is not used in Poland. However in the case of application of bacteriostatic agents based on silver salts, e.g., in jug water filter systems consist of cartridges with activated carbon modified by silver compounds, this element may migrate into purified and further consumed water (applied also for preparation of coffee, tea, soup and dilution of concentrated juices) in amounts which provide essential part of daily dose of silver taken orally by human. In this work the results showing the concentration levels of silver released into purified water in the case of application of jug water filter systems with cartridges consist of activated carbon modified with silver compounds and ion exchanger were presented. Study was performed according to British Standard BS 8427:2004 which describes requirements in respect to the performance of jug water filter systems used for the domestic treatment of drinking water The concentrations of silver in challenge water purified by jug water filter systems were determined using validated method of determination of silver by inductively coupled plasma optical emission spectrometry technique (ICP-OES). In accordance to type of jug water filter systems applied grand mean of silver concentrations achieved during whole cycle of exploitations of product (including possibility of filtrations of 100 l of water) were in the range 0.0022 mg/l-0.0175 mg/l, which is not provided essential human health risk.

[Determination of boron content in natural mineral and spring waters by ICP-OES technique]. / Oznaczanie zawartosci boru w naturalnych wodach mineralnych i zródlanych technika ICP-OES.

Maximum admissible level of boron concentration in water intended for human consumption and in natural mineral and spring waters is usually estimated taking into account actual WHO criteria and requirements listed in Directive No 98/83/EC - 1 mg/l. In majority countries of European Union maximum admissible level of boron in water intended for human consumption is 1 mg/l, however in Slovakia and in Netherlands maximum admissible levels of this element are 0.3 mg/l and 0.5 mg/l, respectively. In this work developed and validated method of determination of boron by inductively coupled plasma emission spectrometry technique was applied for determination of this element in 26 natural mineral and spring waters. Concentrations of boron determined in sixteen mineral and spring waters analyzed were in the range from 0.029 mg/l to 0.552 mg/l while in ten waters analyzed the contents of boron were below 0.026 mg/l. The contents of boron in analyzed waters were below maximum admissible level in Poland presented in the Decree of Minister of Health from 29 March 2007 on the quality of water intended for human consumption and were not dangerous for human health.

[Investigation of concentration levels of chromium(VI) in bottled mineral and spring waters by high performance ion chromatography technique with application of postcolumn reaction with 1,5-diphenylcarbazide and VIS detection]. / Badanie poziomów stezen chromu(VI) w butelkowanych wodach mineralnych i zródlanych technika wysokosprawnej chromatografii jonowej z wykorzystaniem reakcji postkolumnowej z 1,5-difenylokarbazydem i detekcji VIS.

The aim of this work was optimization and validation of the method of determination of Cr(VI) existing in the form of chromate(VI) in mineral and spring waters by High Performance Ion Chromatography (HPIC) technique with application of postcolumn reaction with 1,5-diphenylcarbazide and VIS detection. Optimization of the method performed with the use of initial apparatus parameters and chromatographic conditions from the Method 218.6 allowed to lowering detection limit for Cr(VI) from 400 ng/l to 2 ng/l. Thanks to very low detection limit achieved it was possible to determine of Cr(VI) concentrations in 25 mineral and spring waters presented at Polish market. In the cases of four mineral and spring waters analyzed, determined Cr(VI) concentrations were below of quantification limit (< 4 ng/l) but simultaneously in another mineral and spring waters the concentrations of chromium(VI) were determined in the range of 5.6 - 1281 ng/l. The fact of existence of different Cr(VI) concentrations in investigated waters could be connected with secondary contamination of mineral and spring waters by chromium coming from metal installations and fittings. One should be underlined that even the highest determined concentration level of chromium(VI) was below of the maximum admissible concentration of total chromium presented in Polish Decree of Minister of Health from April 29th 2004. Therefore after taking into account determined in this work concentration of Cr(VI), the consumption of all waters analyzed in this study does not lead to essential human health risk.

Application of bimodal distribution to the detection of changes in uranium concentration in drinking water collected by random daytime sampling method from a large water supply zone.

The random daytime (RDT) sampling method was used for the first time in the assessment of average weekly exposure to uranium through drinking water in a large water supply zone. Data set of uranium concentrations determined in 106 RDT samples collected in three runs from the water supply zone in Wroclaw (Poland), cannot be simply described by normal or log-normal distributions. Therefore, a numerical method designed for the detection and calculation of bimodal distribution was applied. The extracted two distributions containing data from the summer season of 2011 and the winter season of 2012 (nI=72) and from the summer season of 2013 (nII=34) allowed to estimate means of U concentrations in drinking water: 0.947 µg/L and 1.23 µg/L, respectively. As the removal efficiency of uranium during applied treatment process is negligible, the effect of increase in uranium concentration can be explained by higher U concentration in the surface-infiltration water used for the production of drinking water. During the summer season of 2013, heavy rains were observed in Lower Silesia region, causing floods over the territory of the entire region. Fluctuations in uranium concentrations in surface-infiltration water can be attributed to releases of uranium from specific sources - migration from phosphate fertilizers and leaching from mineral deposits. Thus, exposure to uranium through drinking water may increase during extreme rainfall events. The average chronic weekly intakes of uranium through drinking water, estimated on the basis of central values of the extracted normal distributions, accounted for 3.2% and 4.1% of tolerable weekly intake.