Daily Bulletin

The Conversation

  • Written by Emma Beckett, Lecturer (Food Science and Human Nutrition), School of Environmental and Life Sciences, University of Newcastle
Some of our foods have nano particles in them – should we be worried?

We choose to spend money on household items based on how they look, feel and taste, and how we think they might make our lives better.

Manufacturers apply nanotechnology – a field of technology that makes use of effects that happen at the nanoscale – to create the properties we want in such items. For example, whiteness in toothpaste, or preventing growth of bacteria in socks.

One nanometre is one billionth of a metre. Chemical and physical interactions at the nanoscale are way smaller than our eyes can see. Medicines, tiny sensors, fast computers and food science are all ways we can put nanotechnology to use.

Read more: Why nanotechnology is more than just a buzzword

But some people are concerned nanoparticles may present health risks. Recently France announced one nanoscale food additive will be banned from 2020 due to a lack of evidence about its safety.

Here’s what we know about nanotechnology in food.

What are nanoparticles?

Nanoparticles are extremely tiny particles. Their external dimensions are smaller than 100 nanometres, or 0.0001 of a millimetre. That’s pretty small!

Not all nanoparticles are the same. The can be made of all kinds of different things – metals like silver and gold, carbon or even clay – and can have different structures and chemistry. These properties ultimately determine how the nanoparticles behave, their functions and whether or not they are safe.

Nanoparticles occur naturally, and can also be manufactured. Naturally occurring nanoparticles can be found in ash, waterways, fine sand and dust, and even biological matter like viruses. When used in medicine, technology or science, nanoparticles are typically manufactured to better control their properties.

The benefits of nanoparticles come from their extremely small sizes. For example, materials can be made stronger, lighter or better electrical conductors. In medicine, nanoparticles can be manufactured to get into difficult-to-reach places in the body. This is useful in the treatment or diagnosis of diseases such as cancer and infections.

But sometimes nanoparticles which you did not intend to ingest get into the body, or small amounts are consumed in products. This leaves some people asking how we know they are safe.

Read more: A guide to the nanotechnology used in the average home

Nanoparticles occur naturally in foods

Firstly, nanoparticles in foods are not new. Nano-sized particles occur naturally in some foods: a good example is milk. Casein micelles in milk are nano-sized spheres made of proteins. By naturally coming together this way, the nutrients in the micelles are more available for us to absorb.

In addition to milk, it is also possible for some food ingredients to naturally assemble into nanoparticle sized units such as micelles. During digestion, our bodies use the bile that comes from our gall bladder to “nanofabricate” the fats we eat into micelles so we can absorb them.

Micelles also allow fats to be mixed more effectively into water – we create micelles when we wash the dishes using detergents.

Nanoparticles can be created during food processing – such as in homogenisation and emulsification, and milling and grinding. They are also shed from metallic cutlery and other cooking instruments over time.

Nanoparticles are in some additives

Common additives like titanium dioxide, a whitening agent, and silicon dioxide, an anticaking agent, can contain nanoparticles. This is because they are added as powders, and some of the powder particles will be nano-sized. These ingredients only make up a small percentage of foods and only a small fraction of them are actually nano-sized.

Titanium dioxide recently made headlines because a study showed it had an effect on bacteria in the guts of mice. This sounds scary, but the effects were seen when mice were given a big dose (about 50mg per kilogram of body weight each day). This is 50 to 25 times the estimated exposure in humans. It was also added to their drinking water, so there was no food around for the particles to bind with through digestion (as is the case when we eat products with nanoparticles in them).

Two reviews commissioned by Food Standards Australia New Zealand in 2015 found current evidence that nanoparticles of titanium dioxide and silicon dioxide are not absorbed better than micro-sized particles (particles a thousand times the size) and that the majority is excreted.

New uses are being explored

Researchers are looking at how nanoparticles might bring new benefits to food. For example, adding nutrients into foods could help us provide better nutrition from processed foods, slow the breakdown of nutrients and help nutrients be absorbed better.

Nano-sized salt and sugar could help make foods healthier. The smaller the particles, the quicker and more easily they can access your taste buds on your tongue, so the less we might need to eat to get that sweet or salty hit. Similarly, using nanoparticles can mean lower levels of additives by helping them mix more easily through products.

Nanoparticles might also be able to extend shelf life, improve safety of foods, and reducing the need for added fats. Testing for toxicity will be an important part of bringing these new technologies to market.

Read more: Nanotechnology could make our food tastier and healthier – but can we stomach it?

But all in all, we have been eating nanoparticles – naturally occurring and in additives – for a long time with no evidence of harm.

Authors: Emma Beckett, Lecturer (Food Science and Human Nutrition), School of Environmental and Life Sciences, University of Newcastle

Read more http://theconversation.com/some-of-our-foods-have-nano-particles-in-them-should-we-be-worried-117193

Writers Wanted

The missing question from New Zealand's cannabis debate: what about personal freedom and individual rights?


NBN upgrades explained: how will they make internet speeds faster? And will the regions miss out?


The Conversation


Did BLM Really Change the US Police Work?

The Black Lives Matter (BLM) movement has proven that the power of the state rests in the hands of the people it governs. Following the death of 46-year-old black American George Floyd in a case of ...

a Guest Writer - avatar a Guest Writer

Scott Morrison: the right man at the right time

Australia is not at war with another nation or ideology in August 2020 but the nation is in conflict. There are serious threats from China and there are many challenges flowing from the pandemic tha...

Greg Rogers - avatar Greg Rogers

Prime Minister National Cabinet Statement

The National Cabinet met today to discuss Australia’s COVID-19 response, the Victoria outbreak, easing restrictions, helping Australians prepare to go back to work in a COVID-safe environment an...

Scott Morrison - avatar Scott Morrison

Business News

What happens to all those pallets?

Pallets — they're not something everyday people often give much thought to. But they're an integral part of any business which receives or distributes large quantities of goods. But once the goo...

News Company - avatar News Company

Ten tips for landing a freelance transcription job

Transcription jobs are known to be popular in the field of freelancing. They offer fantastic job opportunities to a lot of people, but there are some scammers who wait to cheat the freelancers. ...

News Company - avatar News Company

How To Remove Rubbish More Effectively

It can be a big task to remove household rubbish. The hardest part is finding the best way to get rid of your junk. It can be very overwhelming to know exactly where to start with so many option...

News Company - avatar News Company

News Company Media Core

Content & Technology Connecting Global Audiences

More Information - Less Opinion