Researchers in Britain have found a new way to find sewage leaks and sources of pollution: glowing tampons.
In Britain, many old homes have combined pipes to carry out wastewater and surface water, or rain water, sending both to the treatment plant. Newer homes, however, often have two sets of drains, one of which leads directly into lakes and rivers to prevent surface water from being treated.
While this may sound good in theory, leaks or improper installation and maintenance can send waste water through the wrong drain and directly into nearby lakes.
Researchers discovered that tampons are an easy, cheap way to discover which homes have plumbing problems.
Professor David Lerner of the University of Sheffield discovered that the natural cotton used to make tampons is an ideal carrier of optical brighteners, which are used in detergents to make white clothes brighter with light fluorescence, the Washington Post reported. When a UV light is shined on the tampons, it glows blue.
[quote text_size=”small” author=”– Professor David Lerner” author_title=”Lead researcher in study”]
It’s clearly impractical for water companies to do [dye tests] for all the households they supply, but by working back from where pollution is identified and narrowing it down to a particular section of the network, the final step of identifying the source becomes feasible.
Lerner demonstrated that the unused tampons glow for about 30 days after a single five-second dip in a solution of only 0.01 mL detergent per liter of water. The researchers used this test to determine where waste originated. After getting positive tests in what should have been clean water, it was traced back by the pipes. Clean tampons were dipped into each manhole until the source was found.
The test can be used to find the source of “grey water” contamination, or water that has come from showers, laundry and dishwashers that ends up in storm sewers. Grey wash water is a serious contaminant as water from a washing machine can have rotavirus, norovirus, human pathogenic fungi and many strains of fecal bacteria.
According to Wired, the simple tampon test is effective and much cheaper than alternatives like inserting fiber optic cables into sewer systems at a cost of $13 per meter, or spectrophotometers to detect contaminants, which require calibration and training.