Interesting question! In fact, one might go so far as to say from the tone of the question that it might be an alarming question, suitable to mobilize thousands of protestors, the herald of revelations of conspiracy theories!

Alas, nothing so dramatic is occurring here.

Copper(II) sulfate is indeed a biocide suitable for inhibiting the growth of algae, fungus, and bacteria. Fortunately, an infant falls in none of these categories. For an infant, copper is an essential trace nutrient. It is so vital that during the first trimester a fetus' liver actually stores copper against the day when it will need it to catalyze growth and develop essential body systems. An infant actually needs about four times as much copper as an adult. Hence, many infant formulas are fortified with copper.

For a more detailed discussion, check out the Wikipedia page: Copper in health