Dear Colleagues,

Recently I was asked if I had any sound solution for removal of ftalates from Milli-Q water. Currently, the TOC level is approximately 4 ppb, but it would be desirable to lower it 400X to 0.01 ppb.

A strong anion exchanger column, would probably do the job as most of the ftalates exist(?) as anions in the Milli-Q water. We do not know the origin of these ftalates, wherefore it may be plausible to believe that the ftalates also exist as neutral esters. A different approach for removal would therefore be of interest.

Has anyone on this list been dealing with this problem? If so, I would be interested in knowing how the problem was solved.

I assume that you are talking about phthalate esters, which are plasticizers. How do you know that they are in your water?
If this is what you are talking about they probably come from the tubing used to connect your MilliQ system to the faucet, where you get the water from. Instead of trying to remove them, I would think about using a different type of tubing that does not spit out plasticizers.
Please correct me, if I misunderstood your problem!

Ask Millipore for a solution or distill your water (double distiiation is even better). As Uwe mentioned phtalates are plasticizers. They should occurs mostly in PVC, but from a pratical point of view every plastic (maybe without PEEK or teflon) is suspicious.
I once had a collaegue, who prepared deuterated internal standard substances for GC-MS from scratch purely in glassware. Every solvent was distilled, any plastic banned from the lab... as phtalates disturbed the assay.

Three years ago I was working in a lab there we were looking for phtalates in toys. To have phtalates-free glassware we were heating all glassware to 400 degrees Celsius over 4 hours.

As Alex said: Banning every plastics from the lab is the only one solution to get a real phtalates-free environment (special labs use stainless steel furniture!).
For your water: double distillation may be worthy, try it out! But don't use pipette tips made from plastics after this to dose this water!

Dear Colleagues,
thanks for your comments.
Quite often is the most obvious solution, the last to try! You did understand my problem and I will look into the type of tubings that are used and perhaps combine a possible tubing change with an additional step of distillation.

Why do you need to remove phthalates from Milli-Q water? For chromatography or for other purpose?

Phthalate esters are used as plasticizers in poly(vinylchloride) (Tygon) tubing and other vinyl and cellulose ester products. Do you have a piece of tygon tubing connected to the output of your water system? Do you samples touch any other vinyl product. Plastic pipet tips are poly(ethylene) and they are not a source of phthalates, nor are fluoropolymers.

I would expect distillation to not remove phthalates unless distillation was from permanganate or other oxidizing agent that would destroy phthalates.