Emerging contaminants

In 1991, the United States Geological Survey (USGS) initiated a major study called the North American Water Quality Assessment, or NAWQA—(pronounced “knock-a” in government speak). USGS scientists have collected data in all 50 states, for the NAWQA study, which has helped illuminate a new area of chemical concern: emerging contaminants. The emerging contaminants include a wide array of drugs: from antibiotics to Ibuprofen,and Ritalin and Warfarin (an anticoagulant), prescription and nonprescription drugs are found in rivers, downstream of wastewater plant discharge points. There are insecticides and herbicides (often in higher concentrations within cities than out in farm territory from home and garden use), flame retardants, plasticizers, fossil fuel byproducts and Triclosan (the antimicrobial disinfectant that has suddenly shown up in the majority of hand soaps) also in the mix.

The mix is then sucked in at the intake of downstream water plants. Water treatment technology was never designed to take that stuff out. One of USGS's study's has a disconcerting finding: "This study shows that some chemicals found in commercial household products survive [wastewater] treatment, ecologic conditions between a [wastewater plant] discharge and a [drinking water] intake, and [drinking water] treatment.

Scientists acknowledge that there are more questions than answers right now. They don't know what impact these chemicals have when we drink the water (and tap water is as safe, or possibly safer, than bottled water so don't choose bottled over tap). But, the question is critically important to study: What impact do the tiny traces of these emerging contaminants have on us?