Honestly, we haven't really thought of using tampons for anything besides their intended purpose — not since middle school pranks, at least. Researchers in the U.K., however, have learned that tampons are an excellent and cheap way to monitor water quality in rivers and streams.
David Lerner, PhD, a professor at the University of Sheffield, wanted to find a low-cost method of testing for water contamination — one that anyone could use. He ended up with a variation of a U.S. Environmental Protective Agency technique that used cotton pads for sampling water. Except he used cheap, absorbent tampons instead. As WIRED explains, "gray" water from your dishwasher, washing machine, and shower normally drains into a sanitary sewer system where it gets treated. Runoff from rain and overzealous sprinkler systems, on the other hand, drains into storm sewers that feed directly into natural waterways. If gray water makes its way into these waterways, either deliberately or because of poor plumbing, it's bad news: That water contains a host of bacteria, fungi, and viruses. The water also often contains a powerful identifier called optical brighteners — the stuff in laundry detergents that makes your whites extra-white. These chemicals are very sticky (which is partly why they're effective on clothing) and glow brightly under UV light. Tampons can absorb optical brighteners and will glow if they've been exposed to them. So, Dr. Lerner tied tampons (by those handy strings they have!) to bamboo poles in 16 surface sewers — and left them for three days. Sure enough, even very low concentrations of optical brightener were clearly picked up. The total cost of this testing method, including the use of a black light, ran at roughly 30 cents per tampon. Now, Dr. Lerner plans to "go out and dip tampons in the river," he says," in as many places as we can throughout our watershed." This way, he'll easily learn which spots are contaminated. Let's just hope he's buying applicator-free tampons — for other environmental reasons.