Recent reports of whirlpool-associated illnesses have raised public health concerns about the risks associated with whirlpool bathtubs.
Editor's Note: The footnotes denoted in this article are listed at the end under "References."
Recent reports of whirlpool-associated septicemia(1), skin infections(2), urinary tract infections(3), pneumonia(4), legionellosis and Pontiac fever(5,6) have raised serious public health concerns about the risks associated with whirlpool bathtubs. To assess these risks, whirlpool bath water samples were aseptically collected from private homes and hotels from across the United States. This article deals with whirlpool bathtubs that are filled and drained after each use, as distinguished from recreational spas and hot tubs.
A typical whirlpool bathtub incorporates a system of inaccessible air and water piping(7). When a bather fills the tub and activates the system, normal flora, dirt, sloughed skin, body fluids, bath oils and additives, fecal matter and soap scum circulate through the system and build up inside the piping as biofilm. Biofilm is abundant in nutrient containing aquatic environments, and due to physiological cooperation, they are inherently more resistant to various antimicrobial treatments and cleaning methods. Manufacturers recommend flushing the system with automatic dishwasher detergent, bleach, vinegar or baking soda(8,9,10), but the effectiveness of those products is highly doubtful (Hendrickson, Connie M. Ph.D., personal communication).