Historically, infant formulas are known to be contaminated by aluminum. This has raised health concerns for exposed infants. Researchers measured the aluminum content of a number of widely used infant formulas to determine if contamination by aluminum.
They found that the concentration of aluminum in ready-made milks varied from about 176 micrograms per liter to about 700 micrograms per liter. The highest concentration was found in a milk for preterm infants. The aluminum content of powders used to make milks varied from about 2.4 to 4.3 micrograms per gram, the highest being a soy-based product.
According to Biomed Central:
“The aluminum content of a range of well known brands of infant formulas remains high ... Recent research demonstrating the vulnerability of infants to early exposure to aluminum serves to highlight an urgent need to reduce the aluminum content of infant formulas to as low a level as is practically possible.”