PVC is one of those plastics that can not be avoided. It carries water and sewerage waste and is used to collect rain water from roofs for collection in tanks etc, These days PVC can found in anything from Childrens toys to clothing. Some studies suggest PVC can leach dioxins into water. UPVC is said to contain less chemicals because of reduced polymers (?) Water tanks are often made from PVC (as opposed to Fibreglass or corrugated iron). Hotouses and Chicken tractors can be made from PVC (frame and hothouse plastic). I have always been more tolerant of plastics (finished product) especially when used in a permanent fixture (like pipes etc, (plastic bags and packaging is another story :-x ) than i am of liquid chemicals. I am currently in a position where i am needing to make and use rabbit feeders using uPVC pipe due to other feeder types causing a waste of around 50% of food. Given my zero tolerance to chemicals (in the liquid form), i find myself questioning whether i should use the PVC feeders or continue with the higher cost and wasted food. Who regularly uses PVC pipe in Permaculture applications, What is the likelyhood dioxins would leach into the food (only used for grain and dry food)...??