As noted in numerous posts on this blog, there is increasing interest by the public and government in the presence of personal care products and pharmaceuticals in surface water, including those used for drinking water supplies. This concern stems from the potential of these contaminants from creating health effects in humans. Thus far, government studies have suggested that the levels of these contaminants is too low to cause health effects for people drinking the water. We do know that fish have been impacted by endocrine disrupting chemicals that results in gender changes in fish thought to be due to the presence of estrogen in the water. The question is if these levels continue to build, will they eventually produce human health effects.
At the recent International Ozone Association (IOA) meeting in Geneva Switzerland, J. L. Walther of the Swiss environmental authority explained that a new regulation is being proposed to require the treatment of secondary urban wastewater treatment effluents to remove up to 80% of these contaminants. It has not yet been made law and the process of getting the regulations in place are just starting, but it appears that the Swiss will be the first to get such a law passed.
Beyond regulations, municipalities are looking at both wastewater and drinking water treatment to see if they can reduce the presence of or remove existing compounds from water. Some have already looked at building systems that anticipate potential regulations down the road. An example if the Clark County Water Reclamation District (Las Vegas, NV), which is building an ozone tertiary treatment plant for this purpose.
At the above mentioned IOA meeting, numerous papers were presented on the application of ozone for this purpose. As in many applications, ozone has the advantage of doing several things at once, e.g. simultaneous disinfection and removal of pharmaceuticals. In addition, ozone has a short lived residual that returns to oxygen, an additional positive for the environment.
While regulation of pharmaceuticals in water may be many years off, the trend toward removing them from water is clearly in place today.