# Breaking Down PCB's in lakes

I was wondering if there is any natural process which breaks down PCBs (Polychlorinated biphenyl).

This is an extremely harmful contaminant that was pumped into various lakes by chemical plants up until about the 1950s. It is very stable, which is why it was used a coolant in these chemical plants. However this toxic substance has greatly impacted lake systems, as the concentration of the PCB is increased in each trophic level of the lake ecosystem (due to biomagnification). Anyways, I was wondering if there was any method to break down the PCBs.

Since they are a chlorine-containing compound, would I have to use something like a sodium or potassium based compound to safely break them down chemically. What do you guys think? Thanks!

• Have a look at advanced oxidation processes, such as Fenton and photo-Fenton reactions, as well as photochemical degradation processes using titanium dioxide. – Klaus-Dieter Warzecha Oct 12 '16 at 4:55
• Thanks so much. This is a good idea. I will look into this and post results! – manavjain8 Oct 14 '16 at 22:09
• The problem is complex. PCBs would be easy to chemically decompose if you could isolate them. But some chemical that you'd put in a lake or river would have to be at high concentration and be more toxic than the PCBs. If you try to dig up the sediment in the Hudson River for 100 miles that is just an impossible task. That frankly is why we need the EPA. The only real answer is to prevent such pollution in the first place. – MaxW Mar 2 '17 at 7:25

According to this abstract$\mathrm{^{[1]}}$, both aerobic and anaerobic processes play a role in the natural degradation of PCB's.