Plus even ignoring heavy metal content, in some areas there might be micro-organisms in tap water (since it is sourced from a natural well or similar), so you'd need to be boiling tap water or risk making a newborn sick (even if your body could easily cope with similar water).
> Talk to your baby’s pediatrician and ask what kind of water you should use when mixing infant formula. The American Academy of Pediatrics (AAP) recommends boiling water to remove impurities and kill germs. While most municipal and public drinking water supplies are required to follow strict regulatory guidelines to be safe, pediatricians generally still suggest using boiled water to mix infant formula, at least for the first three or four months. Since there is no evidence that bottled water is safer than municipal water sources, the AAP says that while parents can use bottled water to mix formula, it needs to be boiled first. You can also use distilled water that has already been purified or ready-to-use formulas, which do not need to be mixed with water.
>Can I use flouridated tap water to mix formula? "Yes, you can use fluoridated water for preparing infant formula. However, if your child is only consuming infant formula mixed with fluoridated water, there may be an increased chance for mild dental fluorosis. To lessen this chance, parents can use low-fluoride bottled water some of the time to mix infant formula; these bottled waters are labeled as de-ionized, purified, demineralized, or distilled, and without any fluoride added after purification treatment. The U.S. Food and Drug Administration (FDA) requires the label to indicate when fluoride is added."
So even if ten thousand of me said this a hundred thousand times, people would still buy the "special" bottled water with a picture of a baby on the label. You have to either just let them do it, or start bottling water and printing reassuring labels. They might wise up by the second or third kid.
Or were you trying to say 'distilled water'?
Distilled water is deionized, but deionized has not necessarily been distilled.
In practice, however, both are overkill for baby formula.
Filtered water is fine unless you live in an area with lead problems.
And what obscene cost for bottles? We have exactly 4 bottles so far for our 4 month old and they were less than $5 each. And new nipples are about $2 each when we needed to change the flow.
Now that’s a good racket.