Oh, we've done our research, alright. The reason many fracking chemicals go unknown is because they're never actually disclosed at all, anywhere, to anyone, ever. 

Fracking was explicitly made exempt from the Safe Water Drinking Act by a piece of energy legislation passed by Congress called the Energy Policy Act of 2005. This exemption allows gas companies to inject unknown and/or toxic materials directly into, below, or adjacent to underground sources of drinking water without reporting the chemicals or the quantities of these chemicals to the government or to the public.