Airdate: Apr 04, 2016
Scientist: Nadine Kabengi
Soil - Organic Filter
Every drop of water we drink has gone through a piece of soil.
Soil Organic Filter
There's a free organic water filter available to us all. Unfortunately, we've taken to clogging the filter with poisons. I'm Jim Metzner and this is the Pulse of the Planet
Kabengi: Soils play a big role in controlling our environmental pollution. As the water comes down, it's going to be filtered through these layers of soils. In that sense, every drop of water that we drink has gone through a piece of soil.
Nadine Kabengi is an assistant professor of geochemistry at Georgia State University. She says that when we dump chemicals, they often stay attached to soil particles.
Kabengi: Arsenic is a poison that has been used to treat cattle for their ticks. Around the turn-of-the-century, they used to have these dipping vats, filling the vat with an arsenic solution and dipping the cattle to clean them. After they're done, that would take that solution and put it on the soil next to the the dipping vat. Little did they know that that action is going to cause that poison - arsenic, to stay in the soil for a really long time.
We came in with a desire to understand how long is that poison going to be stuck on that soil? is it going to come off if it rains? If it comes off, is it going to go all the way into the water?
So after looking at that contamination, unfortunately we had some bad news to report. Arsenic is going to stick to the soil for a really long time. And in terms of possibilities of cleaning up, there's not many options because of how strong they cling to each other.
The best solution of course is not to dump poisons. If they must be disposed of in a landfill, the current thinking is to line the landfill with clay and oxides that attract and hold poisons like arsenic. Pulse of the Planet is made possible in part by the Center for Earth and Environmental Nanotechnology and the National Science Foundation.