Arsenic exposure during embryonic development can cause ischemic heart pathologies later in adulthood which may originate from impairment in proper blood vessel formation. The arsenic-associated detrimental effects are mediated by arsenite (iAs(III)) and its most toxic metabolite, monomethylarsonous acid [MMA (III)]. The impact of MMA (III) on coronary artery development has not yet been studie...

Because of its biological activity, arsenic is involved in an active global geochemical cycle. Arsenic has been found to be transferred to the atmosphere, at least in part, by evolution of trimethyl arsine and similar methyl arsenic compounds. Because of the environmental importance of the several arsenic forms [inorganic arsenic (III) and (V), methylarsonic acid, dimethylarsenic acid, trimethy...

Recent epidemiological studies have reported adverse health effects, including skin cancer, due to low concentrations of arsenic via drinking water. We conducted a study to assess whether low arsenic contaminated ground water affected health of the residents who consumed it. For precise biomonitoring results, the inorganic (trivalent arsenite (As III) and pentavalent arsenate (As V)) and organi...

Inorganic trivalent arsenicals are vicinal thiol-reacting agents, and dithiothreitol (DTT) is a well-known dithiol agent. Interestingly, both decreasing and increasing effects of DTT on arsenic trioxide-induced apoptosis have been reported. We now provide data to show that, at high concentrations, DTT, dimercaptosuccinic acid (DMSA), and dimercaptopropanesulfonic acid (DMPS) decreased arsenic t...

A flow injection on-line sorption preconcentration and separation in a knotted reactor (KR) was coupled to hydride generation atomic fluorescence spectrometry (HG-AFS) for speciation of inorganic arsenic in natural water samples. The method involved on-line formation of the As(III)-pyrrolidinedithiocarbamate (PDC) complex over a sample acidity of 0.001-0.1 mol L(-1) HCl, its adsorption onto the...

Arsenic is an extremely toxic metalloid causing serious health problems. In Southeast Asia, aquifers providing drinking and agricultural water for tens of millions of people are contaminated with arsenic. To reduce nutritional arsenic intake through the consumption of contaminated plants, identification of the mechanisms for arsenic accumulation and detoxification in plants is a prerequisite. P...

Environmental arsenic is a world-wide health issue, making it imperative for us to understand mechanisms of metalloid uptake and detoxification. The predominant intracellular form is the highly mephitic arsenite, which is detoxified by removal from cytosol. What prevents arsenite toxicity as it diffuses through cytosol to efflux systems? Although intracellular copper is regulated by metallochap...

ii I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. Abstract Arsenic is a known carcinogen, causing cancers of the skin, lungs, bladder and kidney. Current research suggests that drinking water is the mo...

OBJECTIVES The purpose of this study was to develop an analytical method for the simultaneous determination of inorganic arsenic [As(III) and As(V)] and monomethylarsonic acid (MMA) in urine by gas chromatography-mass spectrometry (GC-MS) for the biological monitoring of exposure to inorganic arsenic. METHODS Arsenic compounds (after reduction of arsenic to the trivalent state) were derivatiz...

In 1969 it was proposed that the episodic madness suffered by King George III (1738-1820) resulted from an acute hereditary porphyria, variegate porphyria, caused by deficiency of protoporphyrinogen oxidase. The diagnosis was based on the historical archive and a contentious claim that living members of the House of Hanover were affected with the condition. A re-examination of the medical evide...