Chuffed, HVs make me soooo mad! bloody useless response!
I took dd to Greece for three months last year when she was 4.5 - 7.5 months. The situation with the water is that some bottled waters have a high mineral content which would be inappropriate for a babe. My doctor gave me a leaflet which spelled out what the maximum amounts should be, and I took v. great care to make sure that I bought only water that fitted that profile. It was, actually, quite difficult on the Greek island I was on, as many of the waters available had sodium and potassium levels that were way too high.
You need to remember your school chemistry too - the minerals are often only shown in shorthand - eg: sodium is shown as 'Na'. Can't remember the proper names for those.....but if you did chemistry, you'll remember what I'm going on about!
My advise would be to ask your HV (!), or maybe the doctor, or the practice nurse for specific guidance on using bottled waters abroad and take it with you.
Having said all that, the mainstream brands, such as Evian, do tend to fit the profile, but check it.
And I boiled it all - dd survived!