NSF # DMII 0329474

1. Plumbing Materials: Impacts on Drinking Water Quality and Consumer Willingness to Pay Civil & Environmental Engineering: Andrea Dietrich, Marc Edwards, G. V. Loganathan … Food Science and Technology: Susan Duncan Agriculture and Applied Economics: Darrell Bosch … Institute for Community Health: Sharon Dwyer … Virginia Water Center: Tamim Younos … Biological Sciences: Joseph Falkinham PhD Students: J. Cerrato, J. H. Hong, E. Kleczyk, J. Lee, P. Omur-Ozbek, E.Tanellari, Y. Zhang MS Students: J. Cuppett, A. Dudi, M. Durand, A. George, T. Heim, H. Johnson, J. Ladd, N. Murray, C. Nguyen, S. Triantafyllidou Undergraduate Students: S. Abbot, A. Galvis, M. Greenfield, J. Nicholson, K. Robbins, A. Strickhouser, Montana State University, Civil & Environmental Engineering: Anne Camper NSF # DMII 0329474 2. Impact of Plumbing on Odor and Quality of Drinking Water In short-term leaching test for the plumbing materials, cPVC imparted the fewest organic compounds to the water, consumed the least amount of disinfectant, and had few noticeable odors. All other polymer materials imparted distinct odors and organic chemicals, and consumed residual disinfectant. Copper pipe consumed nearly all the residual disinfectant.These effects were most prominent in the first 2 months of material use. ODORS Materials Science and Performance WATER QUALITY 1= minor 5= major impact OVERVIEW: Our interdisciplinary study of materials used in drinking water infrastructure answers inextricably interwoven questions about drinking water conveyance, quality of water at the tap, and “real” costs of household plumbing. Our multi-prong approach integrates: Biochemistry of Materials Degradation and Water Quality, Aesthetics and Analytical Chemistry of Corroded Materials, and Economics, Health and Perception in Consumer Decision-making. A portion of our results are presented here, including: 1) fundamental understanding of chemical corrosion and human response to copper in drinking water; 2) an understanding of how changes in disinfectant type and natural organic matter (in response to current EPA regulations) will alter materials performance to impact water quality, biological stability and aesthetics; and 3) gaining consumer input on home plumbing and its failures. Other aspects of this project include investigating lead in drinking water, evaluating microbial growth in pipes and hot water heaters, and development of tools for use by policy makers and citizens to make informed decisions. Consumer Health and Aesthetic Issues 3. Impacts on Consumer Willingness to Pay Between 45 and 50% of those interviewed were willing to pay an “additional” positive amount for leak-free plumbing materials, with Midwest having the highest percentage. Those who were unwilling to pay more varied from 25 to 30%. 1. Copper Corrosion, Flavor, and Health We discovered that people taste soluble copper but not copper particles, which readily form in drinking water. Copper interacts with salivary proteins, has astringent, bitter and metallic tastes, and produces a retronasal smell. As the copper concentration increases and more particles form, people are not able to detect the flavor even as it approaches levels that cause illness. COSTS Some people never taste copper Region where 50% population can detect FLAVOR and HEALTH Costly Repairs and Water Losses SUMMARY: This interdisciplinary project evaluates interactions of plumbing and water quality to provide science in support of consumer health and concerns. The results will inform the water industry, researchers, regulators, and the public on mechanisms to improve drinking water palatability and safety.