Thar's Gold in That There Poo
Dr. Paul Westerhoff, from the School of Sustainable Engineering and the Built Environment at Arizona State University, has found that samples of sewage from around the United States contained both valuable and toxic metals, mostly in the form of small particles.
It's difficult to know the source, but the fact that these metals were in most of the samples suggests that they come from a variety of sources - household, medical and industrial. Dr. Westerhoff thinks it's possible to harvest these resources and perhaps in doing so reduce releases of other toxins - organics and pathogens - into the environment.
image copyright John Rostron, cc-by-sa-2.0