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Articles by Diane Peters

Diane Peters is a freelance writer and editor.

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This story was originally published by Undark and is reproduced here as part of the Climate Desk collaboration.

In the basement of the Center for Urban Innovation at Ryerson University in Toronto, a lone toilet sits on a raised, tiled platform. Darko Joksimovic, an associate professor of civil engineering, drops a clean bathroom wipe into the bowl and flushes. It swims down a 66-foot pipeline that includes two 90-degree turns and clears it in one go.

He then collects the soggy material and drops it into something called a slosh box. This clear tank agitates a gallon of water at a gentle 18 revolutions per minute for 30 minutes. When that’s done, Joksimovic rinses the wipe over a sieve with inch-wide holes for a minute. The material left on the sieve’s surface gets baked in an oven, and then weighed.

If 95 percent of the material slips away through the holes, Joksimovic will rate it as flushable.

This particular test is on a private-label wipe from a Canadian drug store chain. Only 13 percent of the wipe, which is labeled flushable and designed to be used in the bathroom instead of toilet paper, dispersed after this one-hour test. “It fails,” he says. ... Read more