Experts are calling on the Government to take action after new research showed some types of baby formula contain 100 times more aluminium than breast milk.
A team led by Professor Chris Exley at Keele University found at least twice the amount of aluminium in formula as is allowed in tap water, which they said could pose risks to health.
Top brands including Aptamil, Cow and Gate and Hipp Organic all contained levels of aluminium that are too high, the researchers said.
Their study, published in the journal BMC Pediatrics, examined 30 types of formula sold in the UK, including infant first milks and toddler milks.
It follows on from research published by the team three years ago highlighting the potential dangers of aluminium in formula.
Prof Exley said: “We know an awful lot about aluminium but we don’t know an awful lot about how it impacts on human health.
“People have almost certainly heard about the link with Alzheimer’s disease and other neurological conditions and we know from studies that it influences the way in which bones form.
“Aluminium can also produce anaemia in individuals, which is not then helped by giving people more iron.
“How may this aluminium be impacting on the immediate and long-term health of the baby – these are questions that are still unanswered.
“What we don’t know is whether aluminium is accumulating in the bodies of formula-fed babies. If it is, aluminium has no biological function at all, you have no requirement for it.”
Prof Exley accused manufacturers of complacency over the issue and said it was time for the Government to take steps to issue limits on aluminium in formula.
“We expected something to be done about this since our last research but, if anything, the amount of aluminium in packaging has increased,” he added.
Prof Exley said it was unclear how the aluminium was getting into the milk. “There’s a very good chance that some of this aluminium is coming from the packaging and an equal chance it is in the ingredients. Processing is also likely to be a source.”
Results showed both ready-to-drink and powdered varieties had a similar concentration of aluminium overall, but it was highest in soya-based milks.
Among ready-to-drink types, SMA toddler milk had the lowest concentration, followed by Hipp Organic first infant milk, Aptamil hungry baby milk, SMA first infant milk and Aptamil first milk.