Matches in SemOpenAlex for { <https://semopenalex.org/work/W1982782183> ?p ?o ?g. }
- W1982782183 endingPage "17" @default.
- W1982782183 startingPage "1" @default.
- W1982782183 abstract "Groundwater resources in the Pannonian Basin (Hungary, Romania, Croatia and Serbia) are known to contain elevated naturally occurring As. Published estimates suggest nearly 500,000 people are exposed to levels greater than the EU maximum admissible concentration of 10 μg/L in their drinking water, making it the largest area so affected in Europe. In this study, a variety of groundwaters were collected from Romania and Hungary to elucidate the general geochemistry and identify processes controlling As behaviour. Concentrations ranged from <0.5 to 240 μg/L As(tot), with As predominantly in the reduced As(III) form. Using cluster analysis, four main groups of water were identified. Two groups (1 and 2) showed characteristics of water originating from reducing aquifers of the area with both groups having similar ranges of Fe concentrations, indicating that Fe-reduction occurs in both groups. However, As levels and other redox characteristics were very different. Group 1, indicative of waters dominated by methanogenesis contained high As levels (23–208 μg/L, mean 123 μg/L), with group 2 indicative of waters dominated by SO42--reduction containing low As levels (<0.5–58 μg/L, mean 11.5 μg/L). The remaining two groups were influenced either by (i) geothermal and saline or (ii) surface contamination and rain water inputs. Near absence of As in these groups, combined with positive correlations between δ7Li (an indicator of geothermal inputs) and As(tot) in geothermal/saline influenced waters indicate that elevated As is not from an external input, but is released due to an in-aquifer process. Geochemical reasoning, therefore, implies As mobilisation is controlled by redox processes, most likely microbially mediated reductive dissolution of As bearing Fe-oxides, known to occur in sediments from the area. More important is an overlying retention mechanism determined by the presence or absence of SO42-. Ongoing SO42--reduction will release S2−, removing As from solution either by the formation of As-sulfides, or from sorption onto Fe-sulfide phases. In methanogenic waters, As released by reductive dissolution is not removed from solution and can rise to the high levels observed. Levels of organic C are thought to be the ultimate control on the redox conditions in these 2 groups. High levels of organic C (as found in group 1) would quickly exhaust any SO42- present in the waters, driving the system to methanogenesis and subsequent high levels of As. Group 2 has much lower concentrations of organic C and so SO42- is not exhausted. Therefore, As levels in waters of the Pannonian Basin are controlled not by release but by retention mechanisms, ultimately controlled by levels of TOC and SO42- in the waters. δD and δ18O analysis showed that groundwaters containing elevated As dated mostly from the last ice-age, and are sourced from Late Pliocene to Quaternary aquifers. The importance of TOC and retention capabilities of SO42--reduction have only previously been suggested for recent (Holocene) sediments and groundwater, most notably those in SE Asia as these are the most likely to contain the right combination of factors to drive the system to a redox situation leading to high aqueous As concentrations. In contrast, it is shown here that a much older system containing As bearing Fe-oxides, also has the potential to produce elevated levels of As if the TOC is suitable for the microbial population to drive the system to the correct redox situation and SO42- is either absent or wholly consumed." @default.
- W1982782183 created "2016-06-24" @default.
- W1982782183 creator A5026731917 @default.
- W1982782183 creator A5031601920 @default.
- W1982782183 creator A5032196245 @default.
- W1982782183 creator A5038312037 @default.
- W1982782183 creator A5040599805 @default.
- W1982782183 creator A5057617939 @default.
- W1982782183 creator A5061266648 @default.
- W1982782183 creator A5071758090 @default.
- W1982782183 date "2011-01-01" @default.
- W1982782183 modified "2023-10-15" @default.
- W1982782183 title "Geochemistry and arsenic behaviour in groundwater resources of the Pannonian Basin (Hungary and Romania)" @default.
- W1982782183 cites W1555144344 @default.
- W1982782183 cites W1578467403 @default.
- W1982782183 cites W1586092561 @default.
- W1982782183 cites W1906555328 @default.
- W1982782183 cites W1964415402 @default.
- W1982782183 cites W1971098257 @default.
- W1982782183 cites W1975247044 @default.
- W1982782183 cites W1976700000 @default.
- W1982782183 cites W1979951194 @default.
- W1982782183 cites W1983645125 @default.
- W1982782183 cites W1984020301 @default.
- W1982782183 cites W1985879113 @default.
- W1982782183 cites W1987994286 @default.
- W1982782183 cites W1988035822 @default.
- W1982782183 cites W1988549403 @default.
- W1982782183 cites W1988792104 @default.
- W1982782183 cites W1989025106 @default.
- W1982782183 cites W1992879104 @default.
- W1982782183 cites W1993500004 @default.
- W1982782183 cites W1993657008 @default.
- W1982782183 cites W1994799581 @default.
- W1982782183 cites W1995905481 @default.
- W1982782183 cites W2003221509 @default.
- W1982782183 cites W2010147462 @default.
- W1982782183 cites W2011324582 @default.
- W1982782183 cites W2012395145 @default.
- W1982782183 cites W2015229587 @default.
- W1982782183 cites W2015574230 @default.
- W1982782183 cites W2016702532 @default.
- W1982782183 cites W2019109596 @default.
- W1982782183 cites W2019693936 @default.
- W1982782183 cites W2019916888 @default.
- W1982782183 cites W2020749736 @default.
- W1982782183 cites W2022150898 @default.
- W1982782183 cites W2027442307 @default.
- W1982782183 cites W2028243759 @default.
- W1982782183 cites W2029559633 @default.
- W1982782183 cites W2029946864 @default.
- W1982782183 cites W2035377063 @default.
- W1982782183 cites W2035520687 @default.
- W1982782183 cites W2036203294 @default.
- W1982782183 cites W2036396275 @default.
- W1982782183 cites W2036853439 @default.
- W1982782183 cites W2039246403 @default.
- W1982782183 cites W2043506634 @default.
- W1982782183 cites W2043718814 @default.
- W1982782183 cites W2045069625 @default.
- W1982782183 cites W2050485606 @default.
- W1982782183 cites W2050529306 @default.
- W1982782183 cites W2050750841 @default.
- W1982782183 cites W2052366891 @default.
- W1982782183 cites W2055263955 @default.
- W1982782183 cites W2056541363 @default.
- W1982782183 cites W2058720760 @default.
- W1982782183 cites W2063325446 @default.
- W1982782183 cites W2065149338 @default.
- W1982782183 cites W2065186430 @default.
- W1982782183 cites W2066882591 @default.
- W1982782183 cites W2071940309 @default.
- W1982782183 cites W2078011109 @default.
- W1982782183 cites W2079873964 @default.
- W1982782183 cites W2079990214 @default.
- W1982782183 cites W2082638930 @default.
- W1982782183 cites W2082958762 @default.
- W1982782183 cites W2083394958 @default.
- W1982782183 cites W2085248694 @default.
- W1982782183 cites W2085579659 @default.
- W1982782183 cites W2088239401 @default.
- W1982782183 cites W2090149439 @default.
- W1982782183 cites W2090349830 @default.
- W1982782183 cites W2092059727 @default.
- W1982782183 cites W2094352778 @default.
- W1982782183 cites W2095542878 @default.
- W1982782183 cites W2096849731 @default.
- W1982782183 cites W2100369283 @default.
- W1982782183 cites W2107059050 @default.
- W1982782183 cites W2110225754 @default.
- W1982782183 cites W2116105765 @default.
- W1982782183 cites W2126028255 @default.
- W1982782183 cites W2127777553 @default.
- W1982782183 cites W2128244455 @default.
- W1982782183 cites W2128753028 @default.
- W1982782183 cites W2129968762 @default.
- W1982782183 cites W2132895747 @default.
- W1982782183 cites W2136315576 @default.