Plastic piping is a cheap option for drinking water systems. Ongoing research into the chemicals that leach into drinking water from PEX, HDPE, MDPE, and PVC pipes raises questions about long-term safety. Chemicals used as flame-retardants, softeners, and coatings all diffuse into water, especially at elevated temperatures. This video gives a simplified illustration of the processes at work – our look at new leaching research provides more details on areas of specific concern.