Toilet
The toilet is the primary venue where the Metformin enters the aquatic environment. Metformin is a pharmaceutical used by the growing population suffers from diabetes in Mexico City. Stable in the human metabolic system, the Metformin usually released unchanged through human waste and entered into the soil through sewer system. Although Metformin is biodegradable in soil, its transforming product, Guanylurea, is more stable and more challenging to be broken down.
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Scheurer, Marco, Amandine Michel, Heinz-Jürgen Brauch, Wolfgang Ruck, and Frank Sacher.
"Occurrence and Fate of the Antidiabetic Drug Metformin and Its Metabolite Guanylurea in the Environment and during Drinking Water Treatment." Water Research 46, no. 15 (2012): 4790-802.
