To explore the feasible treatment alternatives for organic contaminant, especially organic arsenic species in the landfill gas (LFG) condensate, a variety of treatment approaches were examined and evaluated in this study. Biological degradation, conventional and advanced oxidation, and physical absorption showed limited effectiveness to convert the methylated arsenic to inorganic arsenic. Rever...

The bond distances in hydrated arsenic oxyacid species in aqueous solution have been studied by EXAFS spectroscopy and large angle X-ray scattering, LAXS. These results have been compared to structures in the solid state, as found in an extensive survey of available crystal structures. Protonated oxygen atoms can be distinguished with a longer As-O distance for both arsenic(V) and arsenic(III) ...

Even though arsenic is one of the most widespread environmental carcinogens, methods of remediation are still limited. In this report we demonstrate that a strain of Pseudomonas putida KT2440 endowed with chromosomal expression of the arsM gene encoding the As(III) S-adenosylmethionine (SAM) methyltransfase from Rhodopseudomonas palustris to remove arsenic from contaminated soil. We genetically...

The identification of water-soluble arsenic species in a kidney of the Tridacna clam by electrospray quadrupole/time-of-flight mass spectrometry (ES Q-TOF MS) was investigated. The species were isolated by three-dimensional LC (size exclusion-anion exchange-cation exchange); the elution of arsenic was monitored by ICPMS. The average accuracy and precision of the molecular mass measurements, stu...

Mono-, di-, tri-, and tetrathioarsenate, as well as methylated arsenic oxy- and thioanions, were determined besides arsenite and arsenate in geothermal waters of Yellowstone National Park using anion-exchange chromatography inductively coupled plasma mass spectrometry. Retention time match with synthetic standards, measured S:As ratios, and molecular electrospray mass spectra support the identi...

The groundwaters collected from three wells in the Blackfoot disease (BFD) area in southwest Taiwan contain, on the average, 671 i 149 r g of total dissolved arsenic/L. The arsenic contents in the well waters of Hsinchu, a city in the northwest of the island where no BFD has ever been reported, are less than 0.7 pg/L. The predominant arsenic species in the well waters of the BFD area is As3+ wi...

BACKGROUND Arsenic is a ubiquitous environmental toxicant, and abnormalities of the skin, lung, kidney, and liver are the most common outcomes of long-term arsenic exposure. This study was designed to investigate the possible mechanisms of genotoxicity induced by arsenic trioxide in human hepatocellular carcinoma cells. METHODS AND RESULTS A mild cytotoxic response of arsenic trioxide was obs...

Here we report on the analysis of two aquatic plant species, Azolla caroliniana and Lemna minor, with respect to tolerance and uptake of co-occurring arsenic, copper, and silicon for use in engineered wetlands. Plants were cultured in nutrient solution that was amended with arsenic (0 or 20 microM), copper (2 or 78 microM), and silicon (0 or 1.8 mM) either singly or in combination. We hypothesi...

Chronic arsenic toxicity (arsenicosis) due to drinking of arsenic contaminated ground water is a major environmental health hazard throughout the world including India and Bangladesh. Chronic exposure to arsenic in drinking water can cause increased risk of skin, lung, kidney, bladder cancer, liver disease and chronic respiratory problems. The exact molecular mechanism of arsenic induced carcin...

In this study we report on the finding of monomethylarsonous acid [MMA(III)] in human urine. This newly identified arsenic species is a key intermediate in the metabolic pathway of arsenic biomethylation, which involves stepwise reduction of pentavalent to trivalent arsenic species followed by oxidative addition of a methyl group. Arsenic speciation was carried out using ion-pair chromatographi...