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Name: Linaya
Status: Student
Grade:  9-12
Location: AZ
Country: United States
Date: October 2006

Is mouthwash effective in killing bad bacteria


Yes, most mouthwashs are effective in killing bacteria, as long as they are antiseptic. Antiseptic mouthwashes contain about 20% or more alcohol (ethanol, ethyl alcohol, etc). The definition of antiseptic is to "make free from living bacteria or other microorganisms." ( Other ingredients help reduce plaque, but it is the ethanol that actually kills the bacteria by denaturing their proteins and dissolving their lipids. 70% Ethanol (30% water) is considered the most effective, though manufacturers wouldn't sell mouthwash with 70% ethanol due to its potential abuse by minors and/or others.

Matt Voss

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