The degree of stripping depended on a range of factors, including the volatility of the chemical, the temperature of the water and the surfacearea available for transfer.
These will be much more effective at filtering contaminated water because the beads will have greater surfacearea for the arsenic to bind to than the plastic chips.
Washing generally involves high temperatures, fine sprays (and hence a large surfacearea) and a lot of sloshing around of water, all of which promote efficient chemical stripping.
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