Vitamin D and health in adults in Australia and New Zealand: a position statement
https://www.mja.com.au/journal/2012/196/11/vitamin-d-and-health-adults-australia-and-new-zealand-position-statement

Ian, I'm confused by your interpretation of my link.

The WHO defines "A chronic condition is a human health condition or disease that is persistent or otherwise long-lasting in its effects."

The MJA article I linked to quotes research in stating:
"An estimated 31% of adults in Australia have inadequate vitamin D status (serum 25-hydroxyvitamin D [25-OHD] level < 50 nmol/L), increasing to more than 50% in women during winter–spring and in people residing in southern states."

I'm not a lecturer in pharmacology like you, but doesn't 31% of Australian adults make that a chronic condition?

Gregory Crocetti - the term "chronic" refers to the time-course of a condition, not the prevalence or severity (as in acute vs chronic).

The MJA article you linked to starts out saying "The prevalence of vitamin D deficiency varies, with the groups at greatest risk including housebound, community-dwelling older and/or disabled people, those in residential care, dark-skinned people (particularly those modestly dressed), and other people who regularly avoid sun exposure or work indoors."

The quoted incidence has been averaged across the population, but that does not mean that all the population is equally affected.

What does your research into sunscreen and dermatology show? I can't find any of your publications - only your comments on behalf of Friends of the Earth.

Thanks for the clarification Sue.
I realised I wasn't responding well to the definition as I looked back at my posted comment!

I'm no expert in human physiology, but my understanding of vitamin D was that it slowly builds up and depletes from our bodies - depending on season, sun exposure, diet, etc.

I would have thought that a widespread deficiency (in 31% of Australians), suggests that a serious proportion of Australians have long-term problems producing enough vitamin D.

Therefore, when Ian M. wrote, "there isn't a chronic vitamin D deficiency in our society", I disagreed, because I think it could be a long-term problem for many Australians.

I'm not sure what you mean by asking about our "research into sunscreen and dermatology"?
Perhaps you misunderstand - Friends of the Earth is a social justice and environmental organisation.
Our Nanotechnology Project seeks to encourage an active public discourse into our use of nanomaterials in our daily lives, rather than the status quo - blind acceptance of untested new technologies....many of which we don't need - such as nano-silver socks.

So here I am, actively engaging curious and intelligent people like yourself, to ask questions and sometimes try to answer them.
We are a very small organisation with an extraordinarily small budget compared to almost everyone else...so no, we don't really conduct scientific research as such.

"I am no expert in human physiology" and "we don't really conduct scientific research as such."

But, Gregory Crocetti, here you are opposing the author of this article, who is an immunotoxicologist and has conducted original research in the area.

On what basis do you disagree with his team's findings?

Sue,
I'm not exactly sure what you're getting at.
Perhaps you're suggesting that members of non-scientific organisations (like Friends of the Earth) are not allowed to read the scientific literature and form their own views?
Or maybe you're suggesting that we're not meant to share and debate those views in a public forum such as this?
Or to challenge the views of an esteemed immunotoxicologist like Paul Wright?
I'm going to give you the benefit of the doubt and assume this is not the case and refer back to the science.

The scientific basis of my disagreement with Paul Wright's above comments can be found in my original response. Further evidence to support these views can be found in the recent FoE report:
http://nano.foe.org.au/sites/default/files/Nano-ingredients%20in%20sunscreen%202012.pdf

Feedback to our reports is always welcome!
cheers,
gregory

Greg, the point of sunscreens is to block high energy UV rays.
UVB can damage our DNA directly, while UVA works by creating free radicals, which then can damage our DNA.
There is no question as to whether nanoparticles are good at creating free radicals. Nanoparticles have an enormous surface to volume ratio compared to bulk particles - and it's on the surfaces where free radicals are created.
The point of the Blue Scope Steel research - which Paul so quickly dismissed above - is that some types of nanoparticles are really aggressive free radicals creators.
Other researchers have repeated these scary findings and conclude that some types of nanoparticles should not be recommended for use in sunscreen.
Yes, the risk of skin cancer is proven.
But who are you to say that the skin cancer risks from sunlight are "far greater" than those posed by (at least some) nanoparticles used in sunscreen?
It's got nothing to do with emotion.

Greg Crocetti, who are you to claim that the cancer risks aren't far greater from sunlight?

Your argument seems to be that nano = bad, yet there is no real link shown in any of the science thus far. Thus, any risks that might be shown to be associated with nanoparticles must be rather small which makes the known and quantifiable risks from not using sunscreen much higher.

So your argument is emotional, because it is taking the precautionary principle and pushing the threshold of plausibility. http://en.wikipedia.org/wiki/Precautionary_principle#Threshold_of_plausibility

Hi Tim,

just to be clear - I'm not saying the risk of skin cancer from sunlight is not greater than the risk posed by nano-scale metal oxides used in sunscreens.
But I'm also not saying the opposite.
Nobody knows for sure...in spite of what Paul Wright says above.
How on earth could we know this yet, given how little research has been conducted?

The position that Friends of the Earth takes is one of precaution.
The precautionary principle is not emotional or anti-scientific, just because it doesn't align with a 'weight of evidence' approach based on limited information.
Hopefully, in a decade or two, we will be able to look back at a whole body of scientific literature which asked (and hopefully answered) questions into different toxicities, exposures, etc.
And hopefully by then, we will all agree øn what these collective results mean.
But until then, many people don't want to opt in to this uncontrolled experiment. And in the meanwhile, we want our regulators (especially the TGA) to force sunscreen companies to fund this research through better regulation, not put the onus on the likes of CSIRO and our universities.
The scientific basis for our arguments can be found in our recent sunscreen report:
http://nano.foe.org.au/sites/default/files/Nano-ingredients%20in%20sunscreen%202012.pdf

We are not nano=bad.
That's so very reductionist of you to suggest this.
If you read my nano-silver report from last year, you'll see we support the important clinical use of nano-silver, while arguing that uncontrolled consumer use will likely increase bacterial resistance to silver...thus diminishing it's clinical value.
Take a read if you're interested:
http://nano.foe.org.au/sites/default/files/Nano-silver_2011%20Aus%20v2%20web.pdf

Similarly, we welcome many of the potential applications of nanotechnology to medicine.
If only nano-scale metal oxides in sunscreens had the same degree of clinical scrutiny....

Greg, you stated the question "who are you to say that the skin cancer risks from sunlight are "far greater"" which implies that you do not believe this statement or that there is no proof of this statement. Are you seriously contending that nano-particles are even in the same ballpark of risk? Because that is what you are implying with the stated question.

Which then brought me to my next point, that you are overstating the precautionary principle. You lack the required evidence to suggest that there is a risk worth mitigating or being cautious about. Essentially you have nothing more than supposition, which is not real evidence. Thus you are applying an emotional fear of the unknown and calling it precaution, when it is actually the Threshold of Plausibility clause.

Now, I should state my bias here, FoE are well known in my field of science (agriculture) for their fear-mongering and anti-science stance on plant breeding, modern agronomic technologies and alignment with pseudo-science groups. So from this I have drawn the conclusion that the FoE doesn't follow the science, but rather makes a decision and then finds evidence to support their position. With regard to nano-particles, I think this is an accurate assessment, as there is a lack of evidence to support your position.

Now this is not to say that I "know" or "believe" nano-particles to be safe, but the risks inherent are very low. Thus exposure in the short to medium term is of low risk and allows plenty of time for you to stop fear-mongering and do some actual research to draw a valid conclusion one way or another.

Tim,
thanks for acknowledging your bias.

It's great you agree that we are not in a position to "know or believe" that nanoparticles are safe.
All we are calling for us better regulation - which essentially means mandatory safety testing & labelling = more research.
I hope you'd agree that can't be a bad thing.

Finally, a summary of risk.
RISK = HAZARD x EXPOSURE
The Hazard posed by nanoparticles is overwhelmingly accepted in scientific literature
Our Exposure to nanoparticles through our skin is the big question

Some limited exposure has been demonstrated by few studies, while several studies have demonstrated no exposure.
Most of these studies have seriously unrealistic conditions, but this has been improving in recent years, especially thanks to the likes of brilliant Australian scientists like Brian Gulson and Maxine McCall.

So yes, there's a chance the risk posed by nanoparticles might end up as great as that posed by the sun alone.
However, without labelling how will we ever be able to know?

Is there a lack of evidence to support our position?
Well, I suggest you read our latest report.
Feedback is always welcome!

Oh, and maybe ask the Europeans if there is any evidence?
The entire European Union is commencing regulation - that is - the mandatory testing and labelling of sunscreens, in just a few months time....due to the perceived risks.
A very costly undertaking without any evidence.

Fingers crossed we see lots more good research into exposure in coming years and can put this question of risk to bed.

In the meanwhile, we would prefer people not to draw premature conclusions and for our regulators to take action.

cheers,
Gregory

Do you eat soap/shampoo? Or do you not use them?

Charles, you must have missed this bit:

"A landmark 2010 Australian study showed that there was little difference between nano or bulk zinc oxide sunscreens because of the negligible amount absorbed into the body (less than 0.01% of the applied dose)."

Adam Zielinski: (not entirely relevant, but...) unlucky choice of example! in the jurisdictions that I know about, soap and shampoo are tested to be safe to consume. I wouldn't try it myself, but it must be known to not be posonous in order to be legally sold.

I agree with Ian's points, but I would also point out that visibility and greasiness are factors in application and use. If you are in a work situation, a greasy sunscreen leads to dirt/grime accumulation, which makes it harder for reapplication, makes the sunscreen less effective and make it more likely to be rubbed off.

Also, please could you provide some links on your last point. It contradicts the Choice article I read on the topic.

Great point Jon.

Zinc oxide has been repeatedly demonstrated to exhibit various forms of toxicity to microorganisms (such as bacteria and algae) and smaller macroscopic life forms such as daphnia and zebrafish.
Different nanomaterials have been seen to bioaccumulate from microbes up through food chains, and nanoparticles of silver and cerium oxide have been demonstrated to block nitrogen fixation in the soil.
The biggest problem with this research so far has been detection - with levels in many of these studies possibly well above realistic exposure levels.

I suspect I'm not alone in hoping like hell this uncontrolled experiment with nanoparticles doesn't play out in the real world as badly as laboratory/simulated experiments suggest they might!

Given the amounts of zinc you would be talking about, the amount of water this is being placed into, and the amount normally in water is far higher (especially if you are talking water that has run through galvanised pipes.

For humans the daily intake level is 10-15mg, water that contains 5-30mg/L starts to show chalky colouring, and problems start occurring when intakes are above 675mg/L http://www.scdhec.gov/environment/water/dwor/docs/Zinc.pdf http://www.saskh2o.ca/PDF-WaterCommittee/Zinc.pdf

Seriously, worry more about the amount of feceal matter in the water or the urine content of your local pool.

Tim, nanoparticles of zinc oxide are very different from the concentrations of ionic zinc you refer to.

Not really Greg. The ZnO is going to react reasonably quickly in solution, given the amount of different chemicals and pH involved, not to mention sunlight and mechanical energy.

Seriously Tim, you need to stop seeing the world as black and white. There's a whole complex world out there...with many shades of grey.

It's so reductionist to say that nanoparticles of zinc oxide will dissolve into zinc ions at a certain rate at certain temperatures, pH, etc.
Sure, this might apply in a test tube reaction in your laboratory.

But nanoparticles are used in the real world.
And in the real world, most nanoparticles typically interact with proteins, lipids and more. And this often results in a corona around the particle.

Here's a link to start you on your journey of learning
http://pubs.acs.org/doi/abs/10.1021/nn202458g?mi=vvhks9&af=R&pageSize=20&publication=40025957&searchText=Search

Enjoy

Greg, please remind yourself of my science background in agriculture. We deal with natural systems and not lab results as a matter of necessity, given that many promising lab experiments have failed in the field due to the complexity involved.

Secondly, from your reference, depending upon the corona formation and the substrate medium (in this case a large body of water) you would more likely end up with an insoluable molecule that will be less likely to be transferable across membranes, or one that is more likely to be broken down due to the attraction of ions (etc) within the medium. Thus, you are discarding the more likely outcome (chemical reaction and disassociation) in favour of the very unlikely (transfer across skin of humans swimming in large bodies of water).

Tim, you claim the protein-coated nanoparticle "would more likely end up with an insoluable molecule that will be less likely to be transferable across membranes".
Again, I'm not sure the latest science agrees with you:
http://www.nature.com/nnano/journal/v7/n12/full/nnano.2012.207.html

I'm really not sure what you're trying to achieve by refuting my concerns with reductionist answers.
I guess your reductionist view of Friends of the Earth is that we are anti-science, anti-technology and anti-progress.
That's a shame, because I see a lot of intelligent, passionate and curious people working around me to try to make the world a safer and happier place for all.

Thanks anyway for the interesting & challenging discussion!

Did you read the reference you cited at all?? Because it cites that the breakdown rate was 0.1% of applied for TiO2. This is a different compound from the ZnO referenced in this article. Regardless, the amount of the metals passing into the skin was tiny, but that is only part of the picture.

Dead skin is what is tested in the lab, live skin doesn't have the same properties and thus even less passes through. Thus the risks for healthy skin (no sores, cuts, etc) are pretty small. Compare this with the cancer risks, which are quite large.

So your conclusion that we should fear these uncertainties is unscientific because you are placing false weighting upon "possible" side effects. I'm pretty sure that Paul wasn't saying "let's stop all research on sunscreen", but instead that there is a misplaced fear of nanoparticles because of people like yourself.

Tim, the point of the PLoS One reference was to demonstrate that the question of dermal penetration (i.e. whether sunscreen nanoparticles can penetrate the skin) is far from resolved.

I agree that dead (excised) skin in this study is far from ideal, because it doesn't have many of the same properties as live skin. But the interesting thing here - is that most historic short-term in vitro studies have found little or no penetration of metal oxides - whereas this piece of latest research finds some evidence of dermal penetration.
Surely, the gold standard we should look to here should be realistic exposures to human subjects...which is what makes the Gulson study the most important benchmark to date. What's needed now is realistic exposures to a diversity of human subjects - children and people with skin conditions such as eczema, acne, etc - and not just healthy adults.

Yes, the proportion of the metal oxide passing into the skin was small...but I think it's quite reasonable to question whether chronic exposure to low doses of nanoparticles might present us with problems down the track.

Finally, I also agree Paul Wright didn't say "let's stop all research on sunscreen".
But Paul did say:
"And nano zinc oxide has been thoroughly assessed for safety when used in sunscreens and in lip products", and
"Rest assured that the nano sunscreens can be used safely"

Do you honestly think this language encourages or inspires our regulators, researchers or funding bodies to dig deeper into this topic?

Maybe it's just me, but it sounds like he's saying scientists have got it all under control....which surely is only going to serve to discourage more research.

Michael

The implication that the toxicologists and other experts in the TGA and Medicines Evaluation Committee are colluding corruptly with industry to let through an unsafe product is outrageous. Why would they risk their careers and reputations in this way? Similarly why would I take the opinion of Dr Crocetti against the carefully considered work of the members of SCCS.

I recommend you read the paper by Berube (J Nanopart Res (2008) 10:23-37. It will open you eyes to the way Friends of the Earth have operated.

Luke, by attacking me (and Friends of the Earth) in this manner you appear to be asserting that you are certain sunscreens are safe for us.

Is this actually your position?
If so, do you really feel you are qualified to understand all of the toxicology & dermatology well enough to make this assertion?

Or are you basing your attack/assertion on the strength of Paul Wright's insistence that sunscreens containing nanoparticles are safe for use?

It's true we have been using zinc oxide in some sunscreens for some decades.
And it's true that any bulk (non-nano) zinc oxide mixture will contain a wide distribution of particle sizes, quite possibly including some tail end in the 'nano-scale' (1-100nm).
So yes, we may have been exposing ourselves to some zinc oxide nanoparticles for decades.

But it's all a numbers game.

It's widely recognised that the largest threat posed by nanomaterials is the potential to create free radicals.
Our cells have the potential to mop up free radicals with enzymes like catalase & superoxide dismutase and systems like glutathione & thioredoxin.
But if our cells are overwhelmed with too many free radicals or stressed for prolonged periods, then the likelihood of damage to membranes, proteins and DNA is increased.
When we changed our typical use of zinc oxide from mostly bulk (with possible small amount of nano) to mostly nano - we greatly increased the level of free radical production.

Which takes us back to the question of exposure....

Michael - I have already done so. I note that Greg's main activity is campaigning against nanoparticles of Zn Oxide in sunscreen and he appears to be passionate about it, but has not conducted original research in the area. I note that his field is environmental microbiology.

Not all vested interests are financial. Also, a declared interest does not invalidate a study - it indicates that the methodology and results should be carefully assessed with that information in mind - as should all research.

What I haven't seen Gregory Crocetti do is what should be done with evaluation of research - critical review. If Gregory is indeed qualified to debate the findings, why doesn't he, rather than just presenting emotive arguments.

Rather than just raising doubts, I would love to see someone critical of the existing research present a cogent analysis: what studies have been done, what were the methods used, what were the results and are they valid?

Thanks for the kind words of support Michael.

I agree with Sue that my experience in environmental microbiology doesn't automatically make me "qualified to debate the findings".

But I would also like to think that doesn't mean my or anyone else's views aren't welcome on the Conversation website.
I stand by my reading of the science in critiquing Paul Wright's claims that:
"nano zinc oxide has been thoroughly assessed for safety when used in sunscreens and in lip products", and
"Rest assured that the nano sunscreens can be used safely"
simply don't stack up.
Our latest critical review of the science can be found in the report:
http://nano.foe.org.au/sites/default/files/Nano-ingredients%20in%20sunscreen%202012.pdf

I've read through the FoE paper that Greg Crocetti refers to. It actually doesn't provide any critical analysis of the research - it merely raises questions about potential risks, based on theoretical concerns.

The article above sites two major reviews (European Union 2012, US Environmental Working Group 2012) - both of which appear to be independent of vested interests and both recommend Zn Oxide sunscreens as being safe and effective - both nano and bulk.

The author cites his own group's research - linked above. As I said before, what I would expect in an informed rebuttal is a critical analysis of these papers, showing how their methodology, data collection, data analysis or conclusions are allegedly wrong.

Science doesn't progress with demands to prove that a proposed substance or remedy will forever be 100% certain to be 100% safe. Life doesn't work like that.

Thanks for reading that Sue. I only got as far as the first couple of reports/papers, saved me reading the rest tonight. I had a feeling that your conclusions were what I was going to find. Another method of obfuscation, referencing papers that don't support your point but you assume no one will bother to read.

Sue, thanks for reading our paper. I'm not sure what to make of your feedback "It actually doesn't provide any critical analysis of the research - it merely raises questions about potential risks, based on theoretical concerns." Huh?
Aren't our "theoretical concerns" based upon a "critical analysis of the research"?

You refer to the US Environmental Working Group's claim that Paul cites (note the 'c') above.
Did you even bother to read their claims before you cited them as evidence of independent views supporting nano-sunscreens?
After clicking on the link Paul provided, it takes you to a page on their website where the term 'nano' doesn't appear once. Digging a little deeper, I find this:
http://breakingnews.ewg.org/2012sunscreen/sunscreens-exposed/nanomaterials-and-hormone-disruptors-in-sunscreens/

Zinc Oxide 36% Very limited skin penetration. Estimated at 0.4% in volunteers for nano- and conventional particle sizes. Unknown whether it is in elemental (harmless) or insoluble particle form (toxicologically harmful). No photoallergy or hormone disruption. Skin cell study found zinc nanoparticles provoked oxidative stress and DNA damage. Coatings may reduce skin reactivity. Zinc inhalation causes lung inflammation.

Titanium Dioxide 23% Very limited skin penetration: penetration of hairless mouse skin: no skin penetration in min-pigs. No photoallergy or hormone disruption. Probable carcinogen when inhaled. Inhaled nanoparticles reach organs, cross placenta and enter brain. Skin damage in vitro.
(citations removed)
Do these summaries equate to "safe and effective"? hardly.

You also refer to the European SCCS review that Paul cites.
If you'd also bothered to read this, you'd see that the entire basis of their position hinged on whether the zinc68 from the Gulson study is absorbed as zinc oxide nanoparticles or ionic zinc.
The authors of this study still don't know how to resolve this question - but at least they are trying - and I wish them the best.

I do appreciate you taking the time to read our report....something Tim Scanlon didn't bother to do before sinking the boot in once again.
But I've got to stop this now, because if you're not going to actually read things before you cite them, I'm wasting my time discussing it with you.

Thanks again for the interesting discussion.
It's a shame Paul Wright didn't feel like joining in.

Reply to Greg Crocetti's post starting "Sue, thanks for reading our paper".

I used the term "critical analysis of the research" assuming an understanding of that term. Critical analysis doesn't just mean being critical of the conclusions - it is a methodology of systematically analysing pieces of research to assess their methodology, data analysis and conclusions.

When critically analysing a piece of research, one might start by defining the research question, and then whether the methodology used adequately addresses the research question. Then a look at the methodology - what did they measure, were the measurements reliably done, were they checked by multiple operators, how were they recorded? Was the study adequately powered to find a significant difference? Was the right technology used for the measurements? Were the data appropriately analysed? Were study biases minimised or defined? How well are the conclusions supported by the data.

Some idea might be obtained from looking at a Cochrane review, for example. Look at how they chose adequate studies to include in the analysis, and how they analysed the studies.

This is the methodology I was looking for in your report, and didn't see. What I saw was a theoretical concern that some nanoparticles of Zinc Oxide might be absorbed, especially through non-intact skin, and that this might be more than is currently absorbed from sunscreens containing a range of ZnOxide particles.

If you think the studies that have already investigated this are wrong, then please tell us how they are wrong, or badly done, or incorrectly analysed, along the lines I have suggested.

Great question Greg....but I don't think anyone has made those comparisons yet!!

The point is that nanoparticles of zinc oxide do not penetrate living human skin. Free radicals are extremely short-lived and so would not reach living tissues. This makes the in vitro cell culture work with free radicals irrelevant to real life. It is also thought that the toxicology in vitro is due to very high local concentrations of zinc ions formed by the dissolution of zinc oxide particles. In a real life dynamic situation such local concentrations would not occur. The fact that zinc oxide does not elicit allergic reactions on the skin is also a strong indication that it does not penetrate the skin.

The problem with tobacco smoke, vehicle exhaust fumes is that you inhale them - inhalation is the principal route by which nanoparticles and noxious gases enter the body and cause damage. Nanoparticles in sunscreens are applied to the skin which forms a protective barrier. UV light generates free radicals if it penetrates the skin. Sunscreens, including nanoparticles of zinc oxide and titanium dioxide, prevent UV radiation from penetrating the skin. Which is why they prevent sunburn,help protect against skin cancer and protect DNA.

Hi Greg,
the bulk of scientific investigations into titanium dioxide and zinc oxide (whether in nano or larger forms) have been conducted separately. What's more, some regulators have handled these quite separately. But the risks aren't so different.
Paul Wright does acknowledge the Blue Scope Steel research in text above, but then somehow dismisses it with the ridiculous statement:
"But this is a completely different type of exposure to nano sunscreen, which is formulated to remain on the skin’s surface."

Scientific experiments suggest that both titanium dioxide and zinc oxide particles demonstrate various forms of toxicity (cytotoxicity, genotoxicity, etc) to different types of human cells. And the smaller the particles, the more toxic they appear to become.

The Blue Scope Steel research found that one of the crystal forms of titanium dioxide - anatase - was a particularly aggressive photocatalyst (free radical creator), although also found that zinc oxide was also fairly nasty. Thus, the authors conclude that nanoparticles of anatase titanium dioxide were responsible for destroying the coating on the Colorbond steel...but they also observed:

"With ‘in-house’ experience of over 40 years of coil coating for this market and with regular monitoring of product performance upon in-service installations, many hundreds of roof inspections have taken place each year. Until around mid-2006 however, no significantly destructive effects of the many sunscreens available, upon the tens of thousands of coil-coated roofs installed over this period, have been reported. With this experience in mind, the failure is therefore viewed as a recent phenomenon, possibly paralleling the most recent sun- screen developments employing nano-particulate metal oxides as UV blockers."