Simone Braeuer

Pregnant women in Timis County, Romania are exposed primarily to low-level (<10 μg/L) arsenic through residential drinking water consumption

Excessive arsenic content in drinking water poses health risks to millions of people worldwide. Inorganic arsenic (iAs) in groundwater exceeding the 10μg/l maximum contaminant level (MCL) set by the World Health Organization (WHO) is characteristic for intermediate-depth aquifers over large areas of the Pannonian Basin in Central Europe. In western Romania, near the border with Hungary, Arad, Bihor, and Timis counties use drinking water coming partially or entirely from iAs contaminated aquifers. In nearby Arad and Bihor counties, more than 45,000 people are exposed to iAs over 10μg/l via public drinking water sources. However, comparable data are unavailable for Timis County. To begin to address this data gap, we determined iAs in 124 public and private Timis County drinking water sources, including wells and taps, used by pregnant women participating in a case-control study of spontaneous loss. Levels in water sources were low overall (median=3.0; range=<0.5-175μg/l), although higher in wells (median=3.1, range=<0.5-1.75) than in community taps (median=2.7, range=<0.5-36.4). In a subsample of 20 control women we measured urine biomarkers of iAs exposure, including iAs (arsenite and arsenate), dimethylarsinic acid (DMA), and methylarsonic acid (MMA). Median values were higher among 10 women using iAs contaminated drinking water sources compared to 10 women using uncontaminated sources for urine total iAs (6.6 vs. 5.0μg/l, P=0.24) and DMA (5.5 vs. 4.2μg/l, P=0.31). The results suggested that the origin of urine total iAs (r=0.35, P=0.13) and DMA (r=0.31, P=0.18) must have been not only iAs in drinking-water but also some other source. Exposure of pregnant women to arsenic via drinking water in Timis County appears to be lower than for surrounding counties; however, it deserves a more definitive investigation as to its origin and the regional distribution of its risk potential.

Arsenic hyperaccumulation and speciation in the edible ink stain bolete (Cyanoboletus pulverulentus)

The edible ink stain bolete (Cyanoboletus pulverulentus) was found to hyperaccumulate arsenic. We analyzed 39 individual collections determined as C. pulverulentus, mostly from the Czech Republic. According to our results, concentrations of arsenic in C. pulverulentus fruit-bodies may reach 1300mgkg-1 dry weight. In most collections, data for total and bioavailable arsenic in underlying soils were collected but no significant correlation between the soil arsenic content and arsenic concentrations in the associated fruit-bodies was found. Within the fruit-bodies, we found the majority of arsenic accumulated in the hymenium. Besides occasional traces of methylarsonic acid (MA), the arsenic speciation in all mushroom samples consisted solely of dimethylarsinic acid (DMA) and no inorganic arsenic was detected. Because of the carcinogenic potential of DMA, C. pulverulentus should not be recommended as an edible mushroom and its consumption should be restricted.

Speciation analysis of elements accumulated in Cystoderma carcharias from clean and smelter-polluted sites

Collections of Cystoderma carcharias sporocarps were sampled from clean and smelter-polluted sites and analyzed for Ag, As, Cd, Cu, Pb, Se, and Zn contents. Concentrations of all elements were significantly higher in samples from the smelter-polluted area. Except for As and Pb, all elements were effectively accumulated in the sporocarps at both clean and polluted sites. With the highest concentration of 604 mg Cd kg-1, C. carcharias can be considered as Cd hyperaccumulator. As revealed by HPLC-ICPQQQMS analysis, the As species in sporocarps from clean and polluted areas involved besides the major arsenobetaine a variety of known and unknown arsenicals; the occurrence of dimethylarsinoylacetate and trimethylarsoniopropionate is reported for the first time for gilled fungi (Agaricales). Size-exclusion chromatography of C. carcharias extracts supported by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and RP-HPLC data indicated that detoxification of intracellular Cd and Cu may largely rely on metallothioneins (MT) or MT-like peptides, not phytochelatins.

Homoarsenocholine – A novel arsenic compound detected for the first time in nature

The arsenic speciation was determined in macrofungi of the Ramaria genus with HPLC coupled to inductively coupled plasma mass spectrometry. Besides arsenic species that are already known for macrofungi, like arsenobetaine or arsenocholine, two compounds that were only known from marine samples so far (trimethylarsoniopropanate and dimethylarsinoylacetate) were found for the first time in a terrestrial sample. An unknown arsenical was isolated and identified as homoarsenocholine. This could be a key intermediate for further elucidation of the biotransformation mechanisms of arsenic.