Absorption of arsenic by edible plants

[ecoli at cix.compulink.co.uk]

This has been an interesting thread.
One point not mentioned is that arsenate shows some chemical 
behaviour similarity to phosphate, the uptake mechanism by plants is 
thought to be similar/the same. Phosphate can be a problem plant 
nutrient because it tends to move very slowly in soil (hence, 
maybe,little evidence of arsenate movement).
I would have little concern about arsenate movement from treated timber 
and, to be absolutely sure, would make certain that the potentially 
affected soil had plenty of phosphate present as this would "crowd out" 
any arsenate that had designs on being taken up by a plant.
Peter Harris
U.K.