I want to use pvc pipe as a frame for my tent. I know that there was a problem with pvc tents. Some additive in the plastic was giving off fumes. Is this the same with the pipe. Any info on this subject would be much appreciated. I know what to look for, yellow leaves and skinny stalks that are hallow. Does anybody know if they are giving off fumes how long it takes for the plants to start showing symptoms. And one last thing I heard that even the tents that were giving off fumes only gave off fumes in high tempatures. It is hard to find any conclusive evidence so any experience would be appreciated.