A professor conquers Germany's mightiest river. Andreas Fath swims the 1,231 kilometers from the source of the Rhine to its mouth. The chemist's mission, along with his team who collect water samples along the way, is to advocate for effective protection of our waters. His analyses reveal a concerning increase in microplastic particles and provide evidence of medications and drugs with unclear effects on our environment. "Pure Water" is the gripping narrative of a great adventure and a plea for more careful management of the world's most precious resource. This is essential for us to protect our waters more effectively and to prevent antibiotics from ending up in our drinking water.