Organic Gardening magazine has done extensive research into the use of PR wood - and proved that it is highly toxic. Food plants should NOT be planted in raised beds made using PT wood. Arsenic levels are more than SEVENTY times those considered safe by the EPA. Seems as though the arsenic immediately begins leaching into the surrounding soil. OG also recommends not buying swing sets made of PT wood, as your children will get the arsenic on their hands, which end up in their mouths, etc., etc., etc. For those wanting the whole story, contact OG. They sell the compilation of their research for a small fee. Robert.