Inactivation of Bacteriophage MS‐2 and poliovirus in copper, galvanized and plastic domestic water pipes

Abstract

Survival of bacteriophage MS‐2 and poliovirus was evaluated in new and aged copper, galvanized and plastic polymer (polybutylene, cross‐linked polyethylene, polyvinylchloride) pipes. Inactivation rates (k = — [log₁₀C_t — log₁₀C₀]/t) were calculated as a log₁₀ reduction h^‐1. Levels of copper leached from copper pipes, over a period of 24 h, ranged from 400–800 μg 1^‐1. Numbers of viable MS‐2 were reduced significantly in copper pipes (k = 0.32) compared to plastic polymer pipes (k: = 0.03). New galvanized pipes showed greater inactivation of MS‐2 (k = 2.57) when compared to new copper pipes, and similar rates were also observed in the aged pipes. Poliovirus showed more resistance (k = 0.015 and 0.009 for copper and galvanized pipes, respectively) to the action of copper and galvanized pipes than MS‐2. Addition of 0.20 (μg 1^‐1 free chlorine to water containing 400 (μg 1^‐1 leached copper significantly enhanced the inactivation of both viruses (k = 4.74 for MS‐2 and 0.04 for poliovirus, respectively) when compared to either copper or chlorine alone. Less copper was released from aged copper pipes compared to the new ones, resulting in a significantly lower inactivation of MS‐2 (new, k = 0.32; aged, k = 0.13). The use of copper or galvanized pipes in water distribution systems may serve as an additional protection against viral contamination.

Keywords:

• bacteriophage MS‐2
• poliovirus
• inactivation
• reduction
• copper
• galvanized
• plastic pipe
• drinking water

Notes

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