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Piperonyl Butoxide


Need help eliminating PBO’s (Piperonyl Butoxide) from my lab tests! Anyone have any knowledge on this? Thank you!


Stop using it!

Sorry I couldn’t resist.

How high are the levels? What is the limit allowed?

Half-life for PB is about 6-19 days.

Absent sunlight, water, or soil microorganisms, you are probably looking at the high side of 19 days for a half-life. Let’s say your target is 1ppm but you are at 3ppm. In 19 days you should be at 1.5ppm and after 13 more days you should be at 0.98ppm. There are many factors influencing this, but you get the idea. I would suggest holding it for the estimated time to reach your target and then retest.


Take a look.


Does it have to be ND or less than 3.0?

Is the pyrethrin not a problem?

I am not sure what the two column titles are, I assume Tested Level and Legal Limit, but I am not sure.


Legal limit is 3.0. Im under the legal limit but would like to reduce it more. This is coming from a indoor grower.

My understanding is that PBO’s work in conjunction with Pyrethrins.


I use this product after harvesting inside the rooms for 24 hrs before flipping for the next round. Could it be that theres residual material floating around the room thats contaminating my pre flower to flower after the flip?


Yeah, it’s like an adjuvant (makes pyrethrin more effective).

Only two ways to lower your levels, use it earlier, or not at all, or wait for half lives. I don’t see why it’s a problem if you are below allowed levels. Does your official test to submit to retail give the actual level or just show pass/fail? Here in Oregon the tester gets the full numbers, but the certificate just shows pass/fail.


That is a huge amount of time for the levels to be that high after another round from just residual, particularly with the amount of UV hitting the surfaces.

Is your drying room and flower room on the same ventilation system? Is there any way for the fog to reach the drying room? Seems more like like drift than residual.

You could also skip the fogger and spray something that isn’t tested for, or buy a cold fogger and manually fog something milder. Killing pests on surfaces between rounds is much easier than killing them on living plants.


On a side note, if you plan on making concentrate from your trim, it is very likely to magnify those levels above the legal limit.


Thanks Dan!