Vocarb 3000 question

[Bigbear]

Hi all. I have been seeing furfural THF, and acetone in some of my P&T runs. I have determined it's not in my water. Furfural and THF can come from wood breakdown. How likeley is it that what I'm seeing comes from the Vocarb backbone? Anyone else see these peaks in their systems?

Thanks
Bear

[Ron]

I see THF when the LC people have been using THF, IPA when they use IPA, etc. My thought is that the organics are coming from the environment where the samples were collected or prepared, probably from the ambient air.

[Bigbear]

I can "buy" your statement, but we do not use THF in our lab. My run yesterday had furfural in every trip blank but none in the samples. The lab water used for the blanks didn't have any furfural in it when blanks were prepared. We use a Tekmar Aquatec 70 autosaampler so sample vials are not opened to take the sample. We use ascorbic acid as our dechlorinating agent, and HCl preservative. Oh yeah I found acetone and acetaldehyde in the blanks as well! none of these compounds were found iin the samples. What's going on here??

[JI2002]

How is the lab water prepared? The contamination likely comes from those procedures.