Could human waste really be a source of valuable metals? Recent studies have shown potential, but realizing said potential is still a long way off in all likelihood.
Huffington Post reported on a study that said human waste may be filled with microscopic particles of gold, silver, platinum, and copper, not to mention several other "nuisance" metals like lead.
More specifically, if these particles—measuring less than 1/100th the width of a human hair—are in human waste or at least entering the sewer system by other means, then they'd eventually make their way to wastewater treatment plants, according to studies, and could thereby be harvested for possible reuse, reduce the needs for mining, and also benefit the environment.
Working where we do, we asked a few of our experts.
"While it's an interesting idea," said our Westerly Wastewater Treatment Plant Superintendent Frank Foley, when asked if there was any chance we could be sitting on a literal gold mine in our collection system, "I’m not sure if we currently have information that would allow us to quantify the amount of precious metals in our ash."
|Westerly Wastewater Treatment Plant, Cleveland|
He continued: "Another key, stated in the articles is that there would be a cost to extracting the metals from the ash. That would also have to be quantified to determine if it would be worth attempting to recover any of the material." Research presented in Denver this week said the recovery of these metals using current technology "may not be commercially viable."
Translation: Waaaaay too expensive.
Precious metals like these are not in our treatment plant permit limits, says Senior Environmental Specialist Elizabeth Toot-Levy, so we don't monitor for them. That makes an assessment more difficult. And while we do monitor industries like plating companies to make sure they are not discharging metals to the waste stream, one we have spoken to in the past about gold plating stated it takes extra precautions to ensure that their precious products are not flushed away.
So could sewage be a future source of the metals that make their way into our cell phones and computers? Time and further study will tell. In the meantime, we'll keep our eyes on what does flow into our plant, because you never know what you'll find.