Investigation of Organotin Compounds in Drinking Water Contacting Aged PVC Pipes

Polyvinyl chloride (PVC) pipe is commonly used in drinking water distribution systems and building plumbing. Organotin compounds (OTCs) utilized in PVC pipe production are a public health concern. Here, we examined the significance of organotin release into water under different scenarios of temperature and stagnation in complementary laboratory and field studies. Over a two-year laboratory experiment, monomethyltin (MMT) concentrations ranged from 88 to 186 ng/L, and dimethyltin (DMT) ranged from 9 to 75 ng/L. Methyltin was also the main organotin species leached from aged PVC with a biofilm and with the biofilm removed. Laboratory studies revealed that initial leaching rates of MMT and DMT in the segment reactors with a biofilm were about 53% lower in 15 year-old pipe segments compared to 2 year-old segments due to increased rates of biodegradation from mature biofilms. Certain PVC and chlorinated PVC (CPVC) pipe systems can cause consumer exposure to trace organotin compounds from drinking water.