Researchers are tapping a well-known female hygiene product as a way to test waterways for sewage pollution. Not only does it work well but it's also far cheaper than the typical conductivity and temperature meter approach.
A UK research team placed tampons, tied to bamboo poles, in 16 surface water sewers and left them in place for three days to test for the presence of gray water contamination from laundry system runoff.
Scientists then tested the tampons under a black light to determine if the tampons had absorbed optical brighteners, or fluorescent whiteners, which are detergent additives. If absorbed, the white tampons glow bright under a black light.
"You do get people looking at you strangely, but the tampon is not that obvious," said Professor David Lerner, a professor of environmental engineering at the University of Sheffield.
"It's cheap, it's easy and it does the detective work," added Lerner, who co-authored a study on the new water pollution tracking strategy. The study was published on March 30 in the Water and Environment Journal.
Traditional methods for monitoring wastewater pollution is through fiber optic cables and spectrophotometers, which require training to use and run much higher in cost than boxes of tampons, noted the researchers.
Now that the approach has proven viable, the research team plans to show local community groups the technique to expand monitoring of waterways. Such efforts can help trace pollution sources and hopefully uncover culprits who may then be prosecuted and ordered by courts to clean up polluted areas.
During the testing of the tampon method, one hurdle the scientists dealt with was the fact that good-intended residents, coming upon the poles of tampons, removed them, thinking they were not appropriate or were some sort of vandalism.
In addition to the tampon-strung-on-poles strategy, researchers also used tampons on string to test contaminated pipe networks by dropping tampons into manholes along roadways and streets.
Oftentimes water pollution is tied to housing pipes not being properly connected to sewer pipes and instead being connected to storm water systems, which are only meant to carry natural water runoff into local waterways.
"Often the only way to be sure a house is misconnected is through a dye test," Lerner said.
While researchers say the tampon testing approach requires more investigation, it presents a very encouraging solution to helping track and map sewage leaks, according to Sandra McLellan, an environmental microbiologist not involved in the study.
"The enormity of what needs to be screened is what makes me excited about this test," McLellan said. "Because it is a low-cost test, it's not hard to do those kinds of [validation] studies."