Arsenic concentrations in soils in raised beds constructed with treated wood were 3 to 4 times of those observed in the soils from beds constructed with cement blocks. Arsenic concentrations in cabbage, green pepper, onion bulbs, and tomatoes grown on raised beds constructed with CCA treated woods were no different than those in vegetables grown in beds that were lined with cement blocks. However, Arsenic from treated woods was observed in onion bulbs. Arsenic Mobilization from Pressure Treated Wood. Arsenic leaching from CCA treated wood into soil was observed and this has a potential to introduce arsenic into the food chain when vegetables are grown in raised beds constructed with CCA treated wood.
Work is in progress on determining soil properties that govern arsenic uptake by plants.