tag:theconversation.com,2011:/nz/topics/nanocrystals-6860/articles
Nanocrystals – The Conversation
2018-08-13T11:52:17Z
tag:theconversation.com,2011:article/100064
2018-08-13T11:52:17Z
2018-08-13T11:52:17Z
Five ways that natural nanotechnology could inspire human design
<figure><img src="https://images.theconversation.com/files/231100/original/file-20180808-142251-ey5sqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/blue-morpho-butterfly-iridescent-tropical-native-484889716">Michael Fitzsimmons/Shutterstock</a></span></figcaption></figure><p>Though nanotechnology is portrayed as a <a href="https://theconversation.com/five-ways-nanotechnology-is-securing-your-future-55254">fairly recent human invention</a>, nature is actually full of nanoscopic architectures. They underpin the essential functions of a variety of life forms, from bacteria to berries, wasps to whales. </p>
<p>In fact, tactful use of the principles of nanoscience can be traced to natural structures that are over 500m-years-old. Below are just five sources of inspiration that scientists could use to create the next generation of human technology.</p>
<h2>1. Structural colours</h2>
<p>The colouration of several types of <a href="https://www.chemistryworld.com/feature/structural-colour/3009020.article">beetles and butterflies</a> is produced by sets of carefully spaced nanoscopic pillars. Made of sugars such as chitosan, or proteins like keratin, the widths of slits between the pillars are engineered to manipulate light to achieve certain colours or effects like iridescence.</p>
<p>One benefit of this strategy is resilience. Pigments tend to bleach with exposure to light, but structural colours are stable for remarkably long periods. <a href="https://doi.org/10.1073/pnas.1210105109">A recent study</a> of structural colouration in metallic-blue marble berries, for example, featured specimens collected in 1974, which had maintained their colour despite being long dead. </p>
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<a href="https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=640&fit=crop&dpr=1 600w, https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=640&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=640&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=804&fit=crop&dpr=1 754w, https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=804&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/228220/original/file-20180718-142414-6o4gw8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=804&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Complex slit architecture in the wings of the butterfly Thecla opisena.</span>
<span class="attribution"><a class="source" href="http://advances.sciencemag.org/content/3/4/e1603119">Science Advances/Wilts et al</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
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<p>Another advantage is that colour can be changed by simply varying the size and shape of the slits, and by filling the pores with liquids or vapours too. In fact, often the first clue to the presence of structural colouration is a vivid colour change after the specimen has been soaked in water. Some wing structures are so sensitive to air density in the slits that colour changes are seen in <a href="https://www.nature.com/articles/s41598-017-01273-7">response to temperature</a> too. </p>
<h2>2. Long range visibility</h2>
<p>In addition to simply deflecting light at an angle to achieve the appearance of colour, some ultra-thin layers of slit panels completely reverse the direction of the travel of light rays. This deflection and blocking of light can work together to create stunning optical effects such as a <a href="https://www.livescience.com/92-advanced-optics-butterfly-wings.html">single butterfly’s wings</a> with <a href="http://rsif.royalsocietypublishing.org/content/1/1/49">half-a-mile visibility</a>, and beetles with <a href="http://science.sciencemag.org/content/315/5810/348">brilliant white scales</a>, measuring a slim five micrometers. In fact, these structures are so impressive that they can outperform artificially engineered structures that are 25 times thicker.</p>
<h2>3. Adhesion</h2>
<p>Gecko feet can bind firmly to practically any solid surface in milliseconds, and detach with no apparent effort. This adhesion is <a href="https://doi.org/10.1073/pnas.192252799">purely physical</a> with <a href="https://webdisk.lclark.edu/xythoswfs/webui/_xy-1594799_1-t_d9VVAITO">no chemical interaction</a> between the feet and surface. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=228&fit=crop&dpr=1 600w, https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=228&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=228&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=287&fit=crop&dpr=1 754w, https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=287&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/228215/original/file-20180718-142438-hrk1sp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=287&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Micro and nanostructure of Gecko feet.</span>
<span class="attribution"><a class="source" href="http://www.pnas.org/content/102/2/385">© 2005, The National Academy of Sciences</a></span>
</figcaption>
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<p>The active adhesive layer of the gecko’s foot is a branched nanoscopic layer of bristles called “spatulae”, which measure about 200 nanometers in length. Several thousand of these spatulae are attached to micron sized “seta”. Both are made of very flexible keratin. Though research into the finer details of the spatulae’s attachment and detachment mechanism is ongoing, the very fact that they operate with no sticky chemical is an impressive feat of design. </p>
<p>Gecko’s feet have other fascinating features too. They are <a href="https://doi.org/10.1073/pnas.0408304102">self-cleaning</a>, resistant to self-matting (the seta don’t stick to each other) and are detached by default (including from each other). These features have <a href="http://rsta.royalsocietypublishing.org/content/366/1870/1575">prompted suggestions</a> that in the future, glues, screws and rivets could all be made from a single process, casting keratin or similar material into different moulds. </p>
<h2>4. Porous strength</h2>
<p>The strongest form of any solid is the single crystal state – think diamonds – in which atoms are present in near perfect order from one end of the object to the other. Things like steel rods, aircraft bodies and car panels are not single crystalline, but polycrystalline, similar in structure to a mosaic of grains. So, in theory, the strength of these materials could be improved by increasing the grain size, or by making the whole structure single crystalline. </p>
<p>Single crystals can be very heavy, but nature has a solution for this in the form of nanostructured pores. The resultant structure – a meso-crystal – is the strongest form of a given solid for its weight category. Sea urchin spines and <a href="https://www.livescience.com/1694-secret-abalone-shell-strength-revealed.html">nacre</a> (mother of pearl) are both made of meso-crystalline forms. These creatures have lightweight shells and yet can reside at great depths where the pressure is high.</p>
<p>In theory, meso-crystalline materials can be manufactured, although using existing processes would require a lot of intricate manipulation. Tiny nanoparticles would have to be spun around until they line up with atomic precision to other parts of the growing mesocrystals, and then they would need to be gelled together around a soft spacer to eventually form a porous network.</p>
<h2>5. Bacterial navigation</h2>
<p><a href="https://www.nature.com/scitable/knowledge/library/bacteria-that-synthesize-nano-sized-compasses-to-15669190">Magnetotactic bacteria</a> posses the extraordinary ability to sense minute magnetic fields, including the Earth’s own, using small chains of nanocrystals called magnetosomes. These are grains sized between 30–50 nanometers, made of either magnetite (a form of iron oxide) or, less commonly, greghite (an iron sulphur combo). Several features of magnetosomes work together to produce a foldable “compass needle”, many times more sensitive than man-made counterparts. </p>
<p>Though these “sensors” are only used for navigating short distances (magnetotactic bacteria are pond-dwelling), their precision is incredible. Not only can they find their way, but varying grain size means that they can retain information, while growth is restricted to the most magnetically sensitive atomic arrangements. </p>
<p>However, as oxygen and sulphur combine voraciously with iron to produce magnetite, greghite or over 50 other compounds – only a few of which are magnetic – great skill is required to selectively produce the correct form, and create the magnetosome chains. Such dexterity is currently beyond our reach but future navigation could be revolutionised if scientists learn how to mimic these structures.</p><img src="https://counter.theconversation.com/content/100064/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Thomas Prabhakar does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>
There are countless nanoscopic architectures in nature, creating iridescence, sticky feet, magnetic navigation – and more.
John Thomas Prabhakar, Lecturer of Physical Chemistry (Nanocrystals and Nanoparticles), Bangor University
Licensed as Creative Commons – attribution, no derivatives.
tag:theconversation.com,2011:article/59246
2016-05-17T10:04:47Z
2016-05-17T10:04:47Z
Nanoparticles in baby formula: should parents be worried?
<figure><img src="https://images.theconversation.com/files/122746/original/image-20160516-15906-1ymu3xg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">What's in the bottle is good for me, right?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/21524179@N08/3669555322">nerissa's ring</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>There’s a lot of stuff you’d expect to find in baby formula: proteins, carbs, vitamins, essential minerals. But parents probably wouldn’t anticipate finding extremely small, needle-like particles. Yet this is exactly what a team of scientists here at Arizona State University <a href="http://www.foe.org/projects/food-and-technology/nanotechnology/baby-formula">recently discovered</a>.</p>
<p>The research, commissioned and published by Friends of the Earth (<a href="http://www.foe.org/">FoE</a>) – an environmental advocacy group – analyzed six commonly available off-the-shelf baby formulas (liquid and powder) and found nanometer-scale needle-like particles in three of them. The particles were made of hydroxyapatite – a poorly soluble calcium-rich mineral. Manufacturers use it to regulate acidity in some foods, and it’s also available as a dietary supplement.</p>
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<a href="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=596&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=596&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=596&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=748&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=748&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122339/original/image-20160512-5088-12g9emr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=748&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Needle-like particles of hydroxyapatite found in infant formula by ASU researchers.</span>
<span class="attribution"><span class="source">Westerhoff and Schoepf/ASU</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Looking at these particles at super-high magnification, it’s hard not to feel a little anxious about feeding them to a baby. They appear sharp and dangerous – not the sort of thing that has any place around infants. And they are “nanoparticles” – a family of ultra-small particles that have been <a href="http://dx.doi.org/10.1038/444267a">raising safety concerns within the scientific community</a> and elsewhere for some years.</p>
<p>For all these reasons, questions like “should infants be ingesting them?” make a lot of sense. However, as is so often the case, the answers are not quite so straightforward.</p>
<h2>What are these tiny needles?</h2>
<p>Calcium is an essential part of a growing infant’s diet, and is a <a href="http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=107.100">legally required component</a> in formula. But not necessarily in the form of hydroxyapatite nanoparticles.</p>
<p>Hydroxyapatite is a tough, durable mineral. It’s naturally made in our bodies as an essential part of bones and teeth – <a href="https://en.wikipedia.org/wiki/Hydroxylapatite">it’s what makes them so strong</a>. So it’s tempting to assume the substance is safe to eat. But just because our bones and teeth are made of the mineral doesn’t automatically make it safe to ingest outright.</p>
<p>The issue here is what the hydroxyapatite in formula might do before it’s digested, dissolved and reconstituted inside babies’ bodies. The size and shape of the particles ingested has a lot to do with how they behave within a living system.</p>
<p>Size and shape can make a difference between <a href="http://www.webmd.com/news/breaking-news/food-additives/20150723/nanoparticles-food-additives">safe and unsafe</a> when it comes to particles in our food. Small particles aren’t necessarily bad. But they can potentially get to parts of our body that larger ones can’t reach. Think through the gut wall, into the bloodstream, and into organs and cells. Ingested nanoscale particles may be able to <a href="http://dx.doi.org/10.1080/02652030701744538">interfere with cells</a> – even beneficial gut microbes – in ways that larger particles don’t.</p>
<p>These possibilities don’t necessarily make nanoparticles harmful. Our bodies are pretty well adapted to handling naturally occurring nanoscale particles – you probably ate some last time you had burnt toast (carbon nanoparticles), or poorly washed vegetables (clay nanoparticles from the soil). And of course, how much of a material we’re exposed to is at least as important as how potentially hazardous it is. </p>
<p>Yet there’s a lot we still don’t know about the safety of intentionally engineered nanoparticles in food. Toxicologists have <a href="http://dx.doi.org/10.1289%2Fehp.7339">started paying close attention to such particles</a>, just in case their tiny size makes them more harmful than otherwise expected.</p>
<p>So where does this leave us with nanoscale hydroxyapatite needles in infant formula?</p>
<h2>What do regulators know about nano-safety?</h2>
<p>Putting particle size to one side for a moment, hydroxyapatite is classified by the US Food and Drug Administration (FDA) as “Generally Regarded As Safe.” That means it considers the material safe for use in food products – at least in a non-nano form. However, <a href="http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/ucm300661.htm">the agency has raised concerns</a> that nanoscale versions of food ingredients may not be as safe as their larger counterparts. </p>
<p>Some manufacturers may be interested in the potential benefits of “nanosizing” – such as increasing the uptake of vitamins and minerals, or altering the physical, textural and sensory properties of foods. But because decreasing particle size may also affect product safety, the FDA indicates that intentionally nanosizing already regulated food ingredients could require regulatory reevaluation.</p>
<p>In other words, even though non-nanoscale hydroxyapatite is “Generally Regarded As Safe,” according to the FDA, the safety of any nanoscale form of the substance would need to be reevaluated before being added to food products.</p>
<p>Despite this size-safety relationship, the FDA confirmed to me that the agency is unaware of <em>any</em> food substance intentionally engineered at the nanoscale that has enough generally available safety data to determine it should be “Generally Regarded As Safe.”</p>
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<figcaption>
<span class="caption">Hydroxyapatite nanoparticles may have different health effects from larger versions of the mineral.</span>
<span class="attribution"><span class="source">Westerhoff and Schoepf/ASU</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
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<p>Casting further uncertainty on the use of nanoscale hydroxyapatite in food, a 2015 report from the European Scientific Committee on Consumer Safety (SCCS) suggests there <a href="http://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_191.pdf">may be some cause for concern</a> when it comes to this particular nanomaterial. </p>
<p>Prompted by the use of nanoscale hydroxyapatite in dental products to strengthen teeth (which they consider “cosmetic products”), the SCCS reviewed published research on the material’s potential to cause harm. Their conclusion?</p>
<blockquote>
<p>The available information indicates that nano-hydroxyapatite in needle-shaped form is of concern in relation to potential toxicity. Therefore, needle-shaped nano-hydroxyapatite should not be used in cosmetic products.</p>
</blockquote>
<p>This recommendation was based on a handful of studies, none of which involved exposing people to the substance. Researchers injected hydroxyapatite needles directly into the bloodstream of rats. Others exposed cells outside the body to the material and observed the effects. In each case, there were tantalizing hints that the small particles interfered in some way with normal biological functions. But the results were insufficient to indicate whether the effects were meaningful in people.</p>
<p>Importantly, these studies didn’t consider what happens when particles like this end up in the digestive system, including the stomach.</p>
<h2>So what happens when a baby eats them?</h2>
<p>The good news is that, according to preliminary studies from ASU researchers, hydroxyapatite needles don’t last long in the digestive system.</p>
<p>This research is still being reviewed for publication. But early indications are that as soon as the needle-like nanoparticles hit the highly acidic fluid in the stomach, they begin to dissolve. So fast in fact, that by the time they leave the stomach – an exceedingly hostile environment – they are no longer the nanoparticles they started out as.</p>
<p>These findings make sense since we know hydroxyapatite dissolves in acids, and small particles typically dissolve faster than larger ones. So maybe nanoscale hydroxyapatite needles in food are safer than they sound.</p>
<p>This doesn’t mean that the nano-needles are completely off the hook, as some of them may get past the stomach intact and reach more vulnerable parts of the gut. But the findings do suggest these ultra-small needle-like particles could be an effective source of dietary calcium – possibly more so than larger or less needle-like particles that may not dissolve as quickly.</p>
<p>Intriguingly, recent research has indicated that calcium phosphate nanoparticles form naturally in our stomachs and go on to be <a href="http://doi.org/10.1038/nnano.2015.19">an important part of our immune system</a>. It’s possible that rapidly dissolving hydroxyapatite nano-needles are actually a boon, providing raw material for these natural and essential nanoparticles.</p>
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<a href="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122747/original/image-20160516-15926-1q2xeo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The formula’s safe, but begs other questions.</span>
<span class="attribution"><span class="source">Andrew Maynard</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tempest in a baby bottle</h2>
<p>And yet, even if these needle-like hydroxyapatite nanoparticles in infant formula are ultimately a good thing, the FoE report raises a number of unresolved questions. Did the manufacturers knowingly add the nanoparticles to their products? How are they and the FDA ensuring the products’ safety? Do consumers have a right to know when they’re feeding their babies nanoparticles?</p>
<p>Whether the manufacturers knowingly added these particles to their formula is not clear. At this point, it’s not even clear why they might have been added, as hydroxyapatite does not appear to be a substantial source of calcium in most formula. (Calcium in formula can come from a number of sources, including milk solids, calcium carbonate and calcium chloride.) If the nanoparticles’ inclusion was intentional, though, current FDA guidelines suggest that the regulator wouldn’t consider the material safe by default, and should be subject to further evaluation.</p>
<p>Certainly, from the data presented, these particles – so uniform in size and shape – look like they were intentionally manufactured to be nanoscale and needle-like. It’s possible they were supplied to the various manufacturers without any indication of their “nano-ness.” This doesn’t absolve the manufacturers of responsibility. But it does suggest that greater scrutiny and accountability is needed in the supply chain for food ingredients.</p>
<p>And regardless of the benefits and risks of nanoparticles in infant formula, parents have a right to know what’s in the products they’re feeding their children. In Europe, food ingredients must be <a href="http://ec.europa.eu/food/safety/docs/labelling_legislation_infographic_food_labelling_rules_2014_en.pdf">legally labeled if they are nanoscale</a>. In the U.S., there is no such requirement, leaving American parents to feel somewhat left in the dark by producers, the FDA and policy makers.</p>
<p>Given the state of science on nanoscale hydroxyapatite in foods, this is as much an issue of trust as it is safety. The FoE report may exaggerate the possible risks, and raise concerns where few are justified. Yet it’s hard to avoid the reality that, if manufacturers are adding nanoparticles to what we feed our children, we need to know more about how to ensure their safety and benefits. How else can we enable informed decisions? </p>
<p>Luckily, current research suggests hydroxyapatite nanoparticles in formula are most likely safe, and arguably, even beneficial. But given how high the stakes are, safety here should not, and indeed cannot, be taken for granted.</p><img src="https://counter.theconversation.com/content/59246/count.gif" alt="The Conversation" width="1" height="1" />
<h4 class="border">Disclosure</h4><p class="fine-print"><em><span>Andrew Maynard receives funding support from the Center for Research on Ingredients Risk (CRIS) at Michigan State University. He is also on the Board of Trustees of the International Life Sciences Association North America. He was an independent reviewer on the Friends of the Earth report on nanoparticles in infant formula</span></em></p>
Microscopic needle-like particles don’t seem like something you’d want to feed a baby. Whether safe or not, the way we deal with nanoscale food additives leaves plenty of other questions.
Andrew Maynard, Director, Risk Innovation Lab, Arizona State University
Licensed as Creative Commons – attribution, no derivatives.