title: Evidence for the role of copper in the injury process of coliform bacteria in drinking water.
abstract: Low levels of copper in chlorine-free distribution water caused injury of coliform populations. Monitoring of 44 drinking water samples indicated that 64% of the coliform population was injured. Physical and chemical parameters were measured, including three heavy metals (Cu, Cd, and Pb). Copper concentrations were important, ranging from 0.007 to 0.54 mg/liter. Statistical analyses of these factors were used to develop a model to predict coliform injury. The model predicted almost 90% injury with a copper concentration near the mean observed value (0.158 mg/liter) in distribution waters. Laboratory studies with copper concentrations of 0.025 and 0.050 mg/liter in an inorganic carbon buffer under controlled conditions of temperature and pH caused over 90% injury within 6 and 2 days, respectively. Studies of the metabolism of injured Escherichia coli cells indicated that the respiratory chain is at least one site of damage in injured cells.
mesh_terms: D002104:Cadmium / Q000032:analysis; D003300:Copper / Q000032:analysis / Q000633:toxicity*; D004755:Enterobacteriaceae / Q000187:drug effects*; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D007854:Lead / Q000032:analysis; D010101:Oxygen Consumption / Q000187:drug effects; D014867:Water / Q000032:analysis; D014871:Water Microbiology; D014881:Water Supply
chemical_list: D002104:Cadmium; D014867:Water; D007854:Lead; D003300:Copper