acetone in wastewater

[VJP]

Hi,
We are seeing acetone in the wastewater (spent tank) and trying to find out the source of acetone.
FYI:
1) Our product contains IPA.
2) Based on the results we got from EPA lab (6 months historical data), we see acetone ranging from 1 to 7 ppm in wastewater.
3) Plant is not dumping acetone contaminated water in the spent tank.
4) It’s not an EPA lab doing anything wrong. We tried 2 different EPA labs and they all got same acetone results.
5) We don't have a procedure for waste water sample collection from spent tank and sample shipment to EPA lab for testing.

I can't think of anything else to find the source of acetone. Anyone has any suggestions or has an experience with this type of problem.
Thanks,

[James_Ball]

I have encountered this one before. If you preserve the samples with acid, the IPA will convert to Acetone. If the effluent you are sampling has a low pH it will also happen. Took us about a month to figure it out the first time a client had this problem, now it is the first thing I ask, do you have IPA in your process and is the effluent acidic?

Take an unpreserved sample and see if the acetone is lower or not there.