CSIRO research suggests nano-particles in suncreen may not be harmful.

Updated February 11, 2014 16:53:00

CSIRO research into nano-particles in sunscreen has found that it is safe to use because the human immune system is able to react to the excess zinc particles. However, critics are warning that the study was not broad enough and only looked only at the effects of zinc oxide and not other ingredients.

Source: The World Today | Duration: 4min 28sec

Topics: nanotechnology, australia


ELEANOR HALL: A new study into the impact of nanoparticles in sunscreen on the human body has shown that the immune system is able to absorb excess zinc as a result of using the protection.*

The study found that the human immune system was able to identify and discard the nanoparticles before they reached the bloodstream.

But critics warn that the study was not broad enough and only looked only at the effects of zinc oxide, and not other ingredients.

Whitney Fitzsimmons reports.

(Music: "Slip, slop, slap" advertisement)

WHITNEY FITZSIMMONS: Since the early 80's, slip slop slap has been the Australian summer catch cry. But in recent years concerns have been raised about the impact of sunscreen on our health.

A new study, conducted by a range of interested scientific groups, has specifically looked at the possible dangers posed by nanoparticles, which are tiny cube shaped particles.

The study's authors which include the CSIRO, the Australian Synchrotron, Monash University, RMIT (Royal Melbourne Institute of Technology) and the Melbourne Centre for Nanofabrictaion have revealed that although these nanoparticles can be absorbed into the skin, the human body is equipped to deal with them before they hit the blood stream.

Simon James is from the CSIRO and the Australian Synchrotron.

SIMON JAMES: We've shown, for the first time, that these type of cells of the immune system, the macrophage, are able to ingest and break down zinc oxide nanoparticles.

WHITNEY FITZSIMMONS: The study, which was conducted in a laboratory, looked at how a white blood cell or macrophage reacted when exposed to zinc oxide nanoparticles. They found that about 60,000 nanoparticles attached to one cell, and that cell was able to breakdown more than half of them.

Simon James.

SIMON JAMES: So in the case of these nanoparticles, there was no real sign of overt toxicity when people used them in sunscreens or in other consumer products. But of course, when you take these things into the lab and had a look at how these zinc oxide nanoparticles interact with lung cells or other cells of the immune system, there are some troubling findings and so, it's always one of these things that when you look at experimental systems, how you relate that back to how things operate in the field is quite difficult.

And so we knew that very small amounts of nanoparticles actually made it into the body from field studies, and what we've basically been able to show is that any that do make it through, the frontline garbage disposal system of the body is able to ingest these things and degrade them up nicely.

WHITNEY FITZSIMMONS: But there have been growing concerns that the ingredients contained in the humble sunscreen may be damaging our health and critics of the study say that it doesn't go far enough.

Louise Sales is the nanotechnology project co-ordinator with Friends of the Earth - a federation of grassroots organisations dedicated to critically looking at new technologies such as nanotechnology.

LOUISE SALES: Well we certainly think that the results from this study are interesting, however we think that to conclude that the use of nanoingredients in sunscreen are safe on the basis of this study is premature.

WHITNEY FITZSIMMONS: The Public Health Association of Australia says that, although it has concerns about nanoparticles, the damage of not using sunscreen far outweighs the current concerns.

Michael Moore is the chief executive of the Public Health Association.

MICHAEL MOORE: The public health issues are of course always ones where we look to avoid any possible risk to health, but where we have two risks in conflict, then we need to make a decision about what is the least problematic, and the least problematic is continuing to use sunscreen.

WHITNEY FITZSIMMONS: This is something the Therapeutic Goods Administration has echoed.

In a statement to the ABC it said, "Australia has the highest rate of skin cancer in the world. The use of sunscreen is a vital way to reduce the risk of developing skin cancer and premature skin ageing.


But Friends of the Earth reject that statement and say that there is mounting evidence to suggest that specific nanoparticles such as titanium dioxide can react with the sun to create free radicals with harmful effects.

Friends of the Earth's Louise Sales.

LOUISE SALES: And the concern is that these free radicals can damage DNA and protein and potentially as a worst case scenario actually increase the risk of skin cancer.

WHITNEY FITZSIMMONS: Despite evidence that the body is able to process any zinc dioxide it absorbs through sunscreen, all parties agree further research into the effects of sunscreen needs to be conducted.

ELEANOR HALL: Whitney Fitzsimmons reporting.

*EDITOR'S NOTE: 11 February 2014: The original broadcast item suggested the CSIRO research had found the use of nanoparticles is safe. The transcript has been amended.