we could do better

I recently wrote about some studies that suggest that our wastewater treatment plants are not effective at removal of DNA fragments and viruses, and I even suggested that UV disinfection for wastewater treatment deserves consideration.  A paper that just came out in Applied and Environmental Microbiology analyzed samples from 129 receiving waters around wastewater treatment plants.  Over half of the environmental samples had E. coli strains identical to those in the wastewater treatment plants, and of those strains, 95% carried virulence genes associated with intestinal or urological pathogens.  The authors conclude that some of the strains originate in animals near the receiving waters, but a large fraction of the virulent strains likely come from wastewater treatment plant effluent.

In other words, this study provides further evidence that our wastewater treatment plants may not be sufficiently protecting human health and the environment.  Wastewater treatment has come a long way in ~60 years, and it is very good at reducing the load of human-derived wastes on the environment.  But as our analytical technology has evolved, it’s becoming clear that we could do better.  We could have cleaner, healthier, safer bodies of water.  We just have to decide if we want to pay for it…