Sample Preparation and Analysis of Arsenic in Rice

There have been a number of recent reports published concerning the levels of arsenic found in rice and rice products. While most crops don’t readily take up much arsenic from the ground, rice absorbs arsenic from soil or water much more effectively than most plants. This is primarily because it is grown in water-flooded conditions, which allow arsenic to be more easily taken up by its roots and stored in the grains. Arsenic is known to concentrate in the outer layers of a grain so it is not surprising that levels differ between white and brown rice. Considerable care must be taken when analyzing a sample like rice in order to achieve an accurate result. This application note describes a method for rice grinding and particle separation by size to allow arsenic analysis of samples.