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ScienceJuly 8, 2017

Sensational headlines and intimidation over ‘potentially toxic’ nanoparticles in baby formula (UPDATED)


Scientist Dr Michelle Dickinson looks at the truth behind the scaremongering headlines over a questionable study– and the disturbing way its Australian commissioners went after her when she wrote about it.

This post has been updated with responses from Friends of the Earth Australia and the New Zealand Science Media Centre. (12 July 2017)

Wow Now there’s a headline that would scare the bejeebers out of you if you were currently using baby formula.

The article, published by the Sydney Morning Herald and reprinted at, goes on to say:

A world-leading team in nanotechnology at Arizona State University tested seven off-the-shelf baby formula products and found two – Nestle’s NAN HA 1 Gold and Nature’s Way Kids Smart 1 – contained needle-shaped hydroxyapatite nanoparticles.

Hydroxyapatite nanoparticles – those sound scary right?

Well, lets start with the long word: hydroxyapatite. This is a naturally forming mineral made from calcium and phosphates.  It is the main material that your bones and teeth are made from and exists in a colloidal form in milk.

When you dry milk to make baby formula, the water is removed and the milk is concentrated down into small particles also known as a powder.

Now let’s move on to the word – nanoparticles.  These are tiny particles with at least one dimension less than 100 nanometres or around 1000 times thinner than the width of your hair.

Your silver jewellery will be giving off silver nanoparticles right now, and your sunscreen will be using them to protect you from UV rays.  They are in our food, our electronics, even our stained glass windows.

So the headline really should instead read:

However that sort of title is not going to sell newspapers.

Still worried? Lets dig deeper into the research.

The study was commissioned and published by Friends of the Earth which is an environmental advocacy group.  In it they analysed six off-the-shelf baby formulas bought in America, five of which were powders and one a liquid concentrate.

They dissolved the baby formula in water, spun it around to pull out the particles and put them into a Transmission Electron Microscope to see what the tiny particles looked like.

What they found were all sorts of shapes and sizes of particles which contained calcium, phosphorous and oxygen. These are the same elements that make up bones and teeth.

When it comes to particles, the shape and size can make a difference between safe and unsafe, as some particles if small enough could move into our bloodstream through the wall of our gut after we eat them.

This doesn’t necessarily mean that they are harmful: every single day we are all inhaling, and eating nanoparticles that are just around us in our environment.

For example, if you had a piece of toast for breakfast, you would likely have eaten carbon nanoparticles, which to the human eye look like the burned bits on the top. I don’t see any headlines scaring people about nano dangers in toast, so where did the “potentially toxic” part of this headline come from?

Well, in 2016 the European Commission published a consumer safety study that looked at nano hydroxyapatite.

Their summary was that “nano-hydroxyapatite in needle shaped form is of concern in relation to potential toxicity in cosmetic products”.

They based this on research which they admitted was not in line with the SCCS Memorandum on Relevance, Adequacy and Quality of Data in Safety Dossiers on Nanomaterials.  None of the studies they looked at actually exposed any people to the substance.  The few studies that were carried out used rats, and the study that caused the most concern injected 50 mg/kg body-weight of needle shaped nano-hydroxyapatite into the tail veins of 6 male Sprague Dawley rats.

Just for context the lethal dose of nano-hydroxyapatite is 200 mg/kg body-weight, so their bloodstreams were filled with some pretty high doses of nano needles.  After 48 hours, they analysed the livers of the rats and found some inflammatory cell infiltration and increased white blood cell levels in the rats.  This study, where rats are injected with medium to high doses of nano hydroxyapatite directly into their bloodstream and is how the particles became labelled “potentially toxic”.  The report clearly shows the other studies where rats that were rubbed with or injected with needle shaped nano hydroxyapatite particles showed little to no reaction.

It’s important to remember when reading this that its not just how much of a material we’re exposed to that is important, but also the pathway to exposure can make a difference.

So what happens to these needle shaped nano hydroxyapatite crystals when your baby ingests them? Well the Friends of the Earth study exposed them to different gastric fluid solutions and found that they rapidly and almost instantaneously dissolved.

Basically this scientific test implies that when your baby drinks the formula, the nanoparticles dissolve in their stomach ready for the calcium and phosphate be absorbed by the body.

The sceptics among you may still be concerned that hydroxyapatite nanoparticles are in baby food, but let me just note that research has shown that we form calcium phosphate nanoparticles naturally in our stomachs to help increase the our intestinal immune system.

For those nano-phobes still among us, it might be worth sharing this image:

It shows that normal human breast milk is naturally composed of nano particles of milk fat casein-protein globules – see, not all nanoparticles are scary or dangerous.

Scientific jargon is being used to scare parents, drawing on evidence from a scientific paper which has findings of no special significance.

Based on current research, the hydroxyapatite nanoparticles found in baby formula are most likely safe, are in small doses, in a form that your baby can easily digest and could even be beneficial for your baby in the long run.

An update …

After I posted this piece on my blog, Friends of the Earth contacted me on Twitter to offer me a copy of the report that they are making their Australian baby formula claims from.

Firstly, the report is not peer reviewed and so can not be treated with the same scientific rigour that the article I refer to in this article can.

Secondly, the report shows that the samples which were bought in Australia, were opened in Australia (I’m assuming not in a clean room) and then transferred to a ziploc bag and mailed to the labs for testing in the US.


Friends of the Earth also felt it appropriate to tag my employer in a Twitter post. I can only assume with the purpose of trying to get me in trouble and jeopardise my career.

In order to clear this up, my blog has always stated in the “about me” section that my writings are purely my opinion and not the views held by my employer. However, I do feel that I should mention that my research for the last 15 years has been in nanoparticles and nanotechnology and my whole career started in nano hydroxyapatite systems and I spent six years using hydroxyapatite in a nanostructured form to try and help remineralise teeth for cavity repair and protection. I also have several years of hands-on experience with the techniques mentioned in the report including SEM, TEM, XPS and XRD and have taught undergraduate and postgraduate courses explaining the principles of these techniques.

I will admit that I have very little experience with baby formula other than making it up for to help friends of mine who are parents.

This post was originally published on Michelle Dickinson’s blog.

Update #2

Following the publication of this post The Spinoff was contacted by Friends of the Earth Australia, authors of the original report, requesting a right of reply. We agreed, with the proviso that we would also be inviting comment from a qualified third party, the Science Media Centre’s Peter Griffin. Below, Griffin’s advice on how to read Friends of the Earth Australia’s response, followed by their response itself.

Peter Griffin, director of the New Zealand Science Media Centre:

The issue for me is this: As the great science communicator Carl Sagan, said “extraordinary claims require extraordinary evidence”. So if an NGO with a long track record of activism against nanoparticles, chemicals, GMOs etc, comes out with a report alleging that nanoparticles in baby food are potentially toxic and the regulator should recall the products immediately, they need to be able to show clearly that there is good cause for doing so. What FoE are claiming amounts to a public health scare – if you are telling parents they could be feeding toxic “needle-like particles” to their babies, you need to have a lot of evidence on your side to back that up.

FoE Australia failed to establish that evidence base, just as their US branch weren’t able to convince the US Food and Drug Administration of the risk associated with these particles when they did their own report over a year ago. That is why, despite them managing to get friendly media to buy their story over last weekend, scientists quickly debunked their claims in the following days.

FoE appear to want FSANZ to follow the precautionary principle, which would require it to prove that something is 100 percent safe before allowing it to be sold in Australia and New Zealand. But that isn’t how the regulator works here or around the world, largely because it is almost impossible to prove something is totally safe.

What they have, is tolerance for a certain amount of risk – what FSANZ calls its “risk appetite”. Where there is uncertainty because there isn’t much data available, they have a very low appetite for risk. They go out and look at the balance of scientific evidence and make a call on whether they’ll allow something to be sold in Australia and New Zealand based on that risk assessment.

It isn’t perfect – the evidence base changes and some ill effects may not become obvious until years later (this is a common argument against mobile phones and the radiation they generate), but it works well enough to protect people while allowing new technologies to emerge. If we did it the other way around, there would be all sorts of things we currently take for granted that would be banned.

Ultimately that’s a values judgement and FoE is at odds with many scientists, policy makers – and ultimately the public – over what the approach should be.

If FoE were really onto something they would have encouraged a group of leading scientists to set up controlled trials on this specific issue and submitted it for peer-review to a top journal. That may then have regulatory implications, but there is a reason they haven’t – because they aren’t able to convince scientists there is a serious risk posed here. More research in the nanoparticle space needs to happen, but the balance of evidence is not in FoE’s favour on this issue.

Louise Sales, Msc., Emerging Tech Project Coordinator, Friends of the Earth Australia:

One thing that has become clear in the last week, following revelations of the presence of the needle-like form of nano-hydroxyapatite in baby formula is that some scientists are concerned it is potentially toxic and some aren’t. Scientific disagreements are not unusual. However, it is important to note that the concerns about the potential toxicity of this substance were initially raised by the European Commission’s Scientific Committee on Consumer Safety (SCCS) and not Friends of the Earth.

The needle like form of nano-hydroxyapatite that was found in two of the brands tested does not naturally occur in milk. The scientists – leading nanometrology experts at Arizona State University – concluded that it was synthetic and had likely been intentionally added.

The SCCS has conducted the only comprehensive review of the toxicity of nano-hydroxyapatite. This concluded that there is insufficient evidence to conclude that the chemical is safe. The committee pointed to studies that suggested that nano-hydroxyapatite might be absorbed through the gums. They also referred to a study that found that the needle-like form of nano-hydroxyapatite caused cell damage in the liver and kidneys of rats. On the basis of these studies they concluded that this form of nano-hydroxyapatite is ‘potentially toxic’ and should not be permitted at any level in oral products such as toothpaste and mouthwash.

Some commentators have attempted to dismiss the SCCS review as irrelevant since it did not look at baby formula. But it is the only comprehensive review looking at the oral toxicity of this substance that we have.

Furthermore, these commentators have failed to provide any new evidence of safety. Some have insisted that that nano-hydroxyapatite will dissolve in digestive juices. However, the SCCS refer to studies which suggest that the particles could be absorbed through the gums. Furthermore, a recent study found that not all the particles are dissolved in the stomach and that they can recrystalise.

Friends of the Earth’s position is simple. Ingredients shouldn’t be used in baby formula unless they have specifically been assessed to be safe. And this isn’t just our position – it’s also the position of the Food Regulation Ministerial Council and is specified in FSANZ’s regulation.

It is important to note that FSANZ itself has said that nano-hydroxyapatite is not permitted in baby formula. The agency removed this statement from its website once it became aware of the test results and is now claiming it is safe – despite having conducted no formal safety assessment. Despite FSANZ’s about face, nano-hydroxyapatite is still not permitted in baby formula and still has not been demonstrated as safe.

Babies are particularly vulnerable to food safety risks since their immune systems are still developing. Often infant formula is the only food an infant receives.

By turning a blind eye to the available evidence and the use of this ingredient in baby formula FSANZ is in clear breach of its own regulations and the guidelines set by the Food Regulation Ministerial Council. These are designed to protect babies and infants. These require pre-market assessment for any substance that doesn’t have a history of safe use in baby formula.

Simply claiming that everything is fine without testing, surveillance or monitoring is not good enough. The New Zealand Minister for Food Safety David Bennett needs to urgently intervene and to hold FSANZ to account.

It is clear that there is a systemic problem with FSANZ. The agency is deeply compromised by its close relations with big food multinationals. It consistently refuses to regulate, ignores legitimate health concerns and won’t act for the public good except in the most extreme cases. The agency needs to be fully investigated and overhauled.

The Spinoff’s science content is made possible thanks to the support of The MacDiarmid Institute for Advanced Materials and Nanotechnology, a national institute devoted to scientific research.

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