Localization and speciation of arsenic and trace elements in rice tissues.
The consumption of arsenic (As) contaminated rice is an important exposure route for humans in countries where rice cultivation employs As contaminated irrigation water. Arsenic toxicity and mobility are a function of its chemical-speciation. The distribution and identification of As in the rice plant are hence necessary to determine the uptake, transformation and potential risk posed by As contaminated rice. In this study we report on the distribution and chemical-speciation of As in rice (Oryza sativa Quest) by X-ray fluorescence (XRF) and X-ray absorption near edge structure (XANES) measurements of rice plants grown in As contaminated paddy water. Investigations of muXRF images from rice tissues found that As was present in all rice tissues, and its presence correlated with the presence of iron at the root surface and copper in the rice leaf. X-ray absorption near edge structure analysis of rice tissues identified that inorganic As was the predominant form of As in all rice tissues studied, and that arsenite became increasingly dominant in the aerial portion of the rice plant.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia. Euan.Smith@unisa.edu.au
Euan
E
Smith
Ivan
I
Kempson
Albert L
AL
Juhasz
John
J
Weber
William M
WM
Skinner
Markus
M
Gräfe
D000383:Agriculture; D001151:Arsenic / Q000032:analysis*; D012275:Oryza / Q000737:chemistry*; D010084:Oxidation-Reduction; D018515:Plant Leaves / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D014131:Trace Elements / Q000032:analysis*
D012989:Soil Pollutants; D014131:Trace Elements; D001151:Arsenic