Plastic or Metal Pipes: Pros and Cons

The Plastics Pipe Institute is the major trade association representing all segments of the plastics pipe industry in North America. For more than 50 years, our members have been involved in the research and advancement of plastic pipe and the promotion of its benefits throughout the world. I was both surprised and disappointed after reading an article by Bethany Halford (C&EN Latest News, "Plastic Plumbing Can Make Water Nasty," Aug. 24) based on a study done by Andrea Dietrich, a researcher at Virginia Tech.

Starting with the title of the brief and carrying through many of the comments in the report, the choice of words tend to shed a negative light on the use of plastic pipe in drinking-water systems. Since C&EN is a publication covering multiple aspects of chemistry, I was quite surprised by the lack of research taken before writing this piece and disappointed by the lack of balance by not comparing plastic pipe to more traditional metal pipe. After reading the article, one can easily come away with the negative impression that only plastic pipe imparts tastes and odors to water, leading to unfounded fear in its use.

As a case in point, while copper has been a material widely used in the U.S. to move drinking water, the fact that copper pipes can deliver a highly metallic taste to water, which can become particularly potent and even toxic when those pipes begin to deteriorate, was excluded. This comes from a study also done by Virginia Tech researchers in 2006.

Generally, all piping systems can impart some taste and odor traits to water. Widely accepted best practices recommend the flushing of all lines and piping systems prior to implementing them for regular consumptive use; any taste or odor characteristics resulting from inactive lines or new installations are quickly and easily remedied through such activity.

What was missing from the article, and from Dietrich's report, was commentary on the substantial economic and health benefits that come from the use of plastic pipe over conventional metal pipes. These two points are the heart of why, as Halford mentions in her article "plastic has started to replace metal as the material of choice for water pipes."

A. (Tony) Radoszewski
Executive Director
Plastics Pipe Institute
Irving, Texas