GAINESVILLE, Fla. -- When 26 children became ill after swimming in a kiddie pool at an Atlanta water park earlier this summer, health investigators said it was because low chlorine levels failed to kill harmful bacteria in the water.
A coating developed by University of Florida engineers and biologists might have prevented the June accident by enabling the pool's filter to trap the E. coli bacteria -- one of many possible applications for the coating, the researchers say.
"The problem is, the filters in pools remove only a small fraction of the bacteria in the water, so they're really dependent on the chlorine for decontamination," said Ben Koopman, a professor in UF's department of environmental engineering sciences. "By using a filter that is enhanced in some way, you gain an additional barrier."
Koopman and three professors in chemical engineering, materials science and engineering and microbiology and cell science developed the coating as part of more than a decade of research in UF's Engineering Research Center (ERC). The Kimberly-Clark Corp. paid for some of the at-least $300,000 devoted to the research, with the ERC also contributing.
Dinesh Shah, professor of chemical engineering and director of the Center for Surface Science and Engineering, said the coating enables pool filters and other types of filters to trap bacteria, viruses and particles as small as 500 angstroms. One angstrom measures one ten-billionth of a meter. Viruses range in size from 500 to 1,000 angstroms, while the smallest bacteria measure about 10,000 angstroms, he said.
The key to the coating's effectiveness is its ability to give the filter a positive electrical charge, Shah said. Viruses, bacteria and tiny particles tend to be negatively charged, so the coating attracts the objects to the filter. The result is decontaminated water without the addition of chlorine or other chemicals, Shah said.
Tests of a coated
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Contact: Aaron Hoover
ahoover@ufl.edu
(352) 2392-0186
University of Florida
5-Aug-1998