Tampons may not be an obvious scientific tool, but engineers from the University of Sheffield have been using them to identify where waste water from baths, washing machines, sinks and showers is polluting our rivers and streams.
The natural, untreated cotton in tampons readily absorbs chemicals commonly used in toilet paper, laundry detergents and shampoos.
These chemicals — known as optical brighteners — are used to enhance whites and brighten colours, and show up under ultra-violet (UV) light, a phenomenon often seen in glowing t-shirts under certain lighting in bars and clubs.
A release from the University of Sheffield said that using a mixture of laboratory tests and field trials, the team from the Faculty of Engineering have shown that when tampons are suspended in water contaminated by even very small amounts of detergents or sewage, they will pick up optical brighteners and glow under ultra-violet light.
The findings have been published in the Water and Environment Journal.
David Lerner who led the study working with colleague Dr Dave Chandler, explained: "The main difficulty with detecting sewage pollution by searching for optical brighteners is finding cotton that does not already contain these chemicals. That's why tampons, being explicitly untreated, provide such a neat solution. Our new method may be unconventional - but it's cheap and it works."