The sun is massive its diameter is about 218 times larger than the earth and with temperatures on the surface reaching 6000C it is hot. Consisting mainly of hydrogen (73%) Helium (25%) it is actually a burning ball of gas that is constantly moving, reacting and radiating heat. The charged plasma surrounds the sun like a massive magnetic force field, occasionally spewing out as solar flares towards the earth. We see this as the beautiful and spectacular northern and southern lights.

The earth takes receives almost all of its energy from the sun and without it, life would not exist. Out of the 386 billion billion megawatts of energy that the sun produces, around 89000 terawatts reach the earth – a terawatt is one trillion watts (1012) (Universe Today)

The sun gave us life and the sun sustains life on this planet so, why do we need sunscreen?

Our fear of the sun is not totally irrational. Excessive sun exposure can lead to skin cancer, indeed 85% of melanoma, basal cell carcinoma and squamous cell carcinoma’s cite the sun as a major trigger. In addition to our health, there are the effects that the sun has on our looks. A quick look at the ingredient list of any of the top anti-ageing brands confirms that sun protection is an anti-ageing priority. Skin damaged by the sun displays more wrinkles, looks thickened or leathery and may also end up with pigmentation problems. Not an attractive proposition in an era when forty is the new twenty, sixty the new thirty and ninety the new sixty!

Third on the “anti-sun” agenda is the suns immunosuppressant power. If like me, you get cold sores as a memento from your day on the beach you would tend to agree that the sun is definitely putting your immune system under stress but is it? Immunosuppresing is actually a good thing. If our bodies didn’t turn down our immune reaction when out in the sun, a small sunburn could turn into an anaphylactic shock rather than just a prickly rash. I know what I would rather have! And the cold sores? Well, for those who harbor this virus in the body, the immunosuppressing action of the sun leaves the gate open just enough for the cold sore virus to kick in. Unfortunately, that is the pay off.
Things are looking bleak out here and we haven’t even mentioned global warming!

But are we being fair? Is the sun really so bad and are our bodies really so ill equip to deal with our daily dose? And what about Vitamin D? To answer some of these questions we decided to look at plants – after all, I have never seen a cactus reach out for the factor 30. What do they have that we don’t?

When I mention the cactus, I automatically think of those huge, western style plants but the truth is that cactus come in all shapes and sized. They belong to the succulent family and while some are adapted to the arid deserts of Arizona, others are more at home in more temperate climates. Try planting a mountain dwelling cactus in the desert and it will get sunburn. Take a desert dwelling cactus to the rainforest and it will get foot rot! It seems that people and plants are not so different.

Desert dwelling cacti have evolved to deal with the suns full force. They have no leaves to preserve water and use hairs, spines and sometimes wax to protect them from the sun. So, it would seem that plants do indeed wear sunscreen.
The problem that people have is our desire to explore. We invented boats, trains then planes to take us everywhere. While this travelling has proved to be of great benefit to humankind, it has contributed to our sun-hate relationship!
Take me for example. I have a skin type of 1 according to the Fitzpatrick scale – just call me burney! I chose to move to Australia with my family five years ago and while the intensity of the sun did lead me to think “is this wise for someone so melanin deficient?” I, along with my equally white family decided to come anyway. Now if I were a plant I would have shriveled and died by now without lots of care, as a person I have managed to live in near perfect harmony with the sun until now. BUT to do that comes with strings attached.

My skin is perfectly adapted to the place that I came from. I am not sure exactly where that is as us Europeans had a liking for cross border travel but let us say that I am more Anglo-Saxon than Greek or Roman. Fair skin is quite useful in dark and gloomy England. There is no need to go to the trouble of making lots of melanin, as there is very little sun to protect against. In addition to sun protection, a study by anthropologist Nina Jablonski showed that skin colour is important in vitamin synthesis. For your body to make vitamin D, a vitamin that helps the body to absorb calcium, the skin needs the sun.

Light skin seemed to have been developed to enable the body to synthesize vitamin D even when there is only low levels of UV light. The darker the skin, the more sun is required to make the vitamin D. This is one reason why darker skinned people living in cooler, darker climates can be at risk of having low Vitamin D levels.
Vitamin D is not the only vitamin to have a sun relationship. Jablonski also showed that foliate can be broken down by too much sun. This may be the main reason why people living nearer the equator developed darker skin – especially as it has been found that you can’t overdose on vitamin D! Foliate is required for neural development and UV radiation has been found to reduce foliate levels in the body.

So, finding myself in a hot, dry climate where the sun’s rays are intense leaves me with a problem. My skin is not adapted to this environment. I need help! It seems that the sun is not the problem. The problem is me.
Of course, those of us who are lucky enough to have a passport reserve our right to travel and make our home base wherever we choose. I have no intention from my new homeland and I doubt that I can get my skin to evolve any quicker by frying it. Therefore, I have to be sensible.

People often ask me “what is the best sunscreen on the market” and my gut reaction is to say “your brain”. Our bodies have been designed to work with the sun; we need to sun to keep us healthy both mentally and physically. Anyone who has visited Sweden in the winter will know the problems that Seasonal Affective Disorder brings on. Ultra-Violet light makes us tick.

There really is nothing to fear with going outside and enjoying a safe, healthy dose of sun. How much is enough? Everyone is different. We carry around the best sunscreen on the market every day – our skin. We just need to read the label and apply common sense frequently.

So, does that mean that commercial sunscreens are defunct? Of course not, but nothing is as broad spectrum and as personally prescribed as your own skin. A commercial sunscreen, however good will still let some sunlight through. This is OK if you are paying attention and listening to your body as you enjoy your day on the beach. We run into problems when we hand over responsibility for our skins safety to the sun lotion. The two need to be used together.
A good broad-spectrum sunscreen and some behavior modification will ensure that going outside is not only safe, it is fun and life affirming. As for the immunosuppressant – nothing suppresses the immune system faster than a depressed person who is depriving their bodies of the good things that nature has to offer and that include the sun.
Come outside.

Amanda Foxon-Hill

Nano Zinc and titanium became popular in the late 1990’s as the technology for making these small particles became more commercially viable. Many companies sell nano sized Zinc and as these ingredients open the door for light weight, high protection, broad spectrum sunscreens to be developed in an inorganic only filter base. Nano Zinc and Titanium have also found use in the anti-ageing and SPF 15 moisturizing cream as formulators became able to develop creams, lotions, sprays and foams that went onto the skin without leaving the wearer a ghostly shade of white. Also as Zinc and Titanium actives work on the surface of the skin, they are preferred in products for babies or for those with sensitive skins – an elegant product offering for this market segment was most welcomed. It seemed that it was sunny side up at every turn!

Unfortunately, with every happy innovation should come a degree of caution. When you take something like Zinc or Titanium and create nanoparticles you not only change the physical characteristics of the particle, you may also change its chemical reactivity. A nanoparticle is a particle who’s size is 100nm or smaller. With an average human hair being 80,000nm across you can see that these things really are tiny. Physically such small particles may be able to enter the body through inhalation of the material when manufacturing, through ingestion (consumer product not wiped off the hands or licked) or through dermal penetration as a consequence of normal product usage. Chemically nanoparticles may be much more reactive than their larger conterparts. They may do all kinds of things that their big brothers and sisters would never dream of doing such as bonding to other chemical ingredients, forming free radicals or otherwise destabilizing the formulation. It soon became clear that more work on the safety of nanoparticles for sunscreens had to be made public.

So, nanoparticles are already in our products but are they safe? What work has been done so far? How do I know what products contain these particles? These are all questions that are being asked by individual consumers, the scientific community and the wider cosmetics industry. Chatting to one of the nano-zinc or titanium manufacturers would ensure you that work has indeed been done to validate their ingredient’s safety. The ingredient manufacturers have carried out numerous tests into the materials safety in use, manufacturing expose and formulation stability. They assure us (consumers / industry members) that the ingredients have been tested and deemed safe under current health and safety criteria and we believe that to be true. That is why we promote and use these ingredients. However, most of the detail contained within these corporate studies remains proprietary information and is by definition not available for the public. This knowledge gap has created a degree of concern. The CSIRO and Macquarie University are working at filling this gap.

Professor Brian Gulson of Macquarie University and Dr Maxine McCall of the CSIRO, on discovering that a stable isotope of Zinc (Zinc 68) was available via Russian manufacturer Isoflex started work to develop a procedure for tracing nanoparticles of Zinc through sunscreen. The aim of the ongoing study has been to trace and quantify the movement of the zinc isotope after applying it in a standard sunscreen base. For the first time a “real life” scientific study into the fate of nano zinc in sun cream would be made available to the public. This study was formulated to follow the path of nano zinc when applied in a “real life” situation. After an initial calibration and safety trial containing three people a larger trial, including UV exposure and over 20 people was initiated. This was the trial that I took part in.

Volunteers from different walks of life came forward to be part of the trial into nano zinc. My appetite had been whetted during the first of two presentations that Brian and Maxine’s team gave at Sydney’s ASCC lecture evenings. I had been a part of the sunscreen industry for ten years as a supplier and hobby formulator and immediately appreciated the power that this type of study could have. Joining me on my journey were students, shift workers, people just wanting a break and some time out at the beach, travelers both returning and current and others who were closely linked to the study staff. All up, we formed what I believed to be an interesting and diverse group of people, there for different reasons but all happy to put their backs on the line in the name of science!

Leading up to the trial we met up at Brian’s house to have our skin type graded – I am a melanin deficient skin type one (out of a possible six) which means that I don’t usually tan and burn readily (see the Fitzpatrick classification Scale.) While I had realized that my skin burned quickly in the Australian sun, I had hoped that I may had some be a more forgiving two or three as that would make life a lot more convenient. The other volunteers slotted in at various points on the scale with all but the very darkest skin type being present. We were also lucky enough to have a wide range of ages – skin changes as you age and can become dryer and thus a less effective barrier.

For this trial a commercial base sunscreen was put together to mimic as closely as possible a “real life” experience. The standard base was also made up again using the tracer Zinc particles at known quantity. The trial was split into two groups, control (non-nano) and nano (with the tracer zinc). Both groups complied with the same test protocol and both sunscreens contained the 68 Zinc tracer (only in the control sunscreen the tracer zinc was in particles larger than 100nm. Efforts to avoid ingestion were vigorously enforced – washing of hands often, no touching of the sunscreen area, each subject having their own numbered top and towel and all contaminated clothes being taken away each night for laundering.

We could not have been luckier with the weather and venue for the trial. The first day was spent lazing around Macquarie University’s excellent outdoor pool. We had to sign in each day with a urine and blood sample then line up to have our sunscreen applied. Once dosed up we were instructed to wait at least 20 minutes for the cream to settle before we were free to go out and either lie or walk around in the sun for a minimum of thirty minutes. This “lab rat” lifestyle did wonders for our karma as we all enjoyed the luxury of a few hours in the day in which to read, take a nap, talk to friends or cram in some extra study. All in all one could not complain!

The remainder of the trial was spent at North Curl Curl surf club which the clear sunny day that Monday brought was just heaven on earth! The trial routine was simple and repetitive: Urine sample between 9-10am, blood at around the same time, sun cream and specially designed sun top on straight after, wait for 20 minutes and then out you go. The urine sample and sunscreen application was repeated after lunch with a 30-minute sun sit /bathe shortly after. The day finished with the sunscreen being wiped off followed by blood and urine collected at around 3.30. Pretty easy and overall quite painless.

As test subjects, we were exposed to UV light for at least an hour each day and the sunscreen for a minimum of four hours a day over a period of five days – adequate time for a skin reactions to develop or skin penetration to take place if it was going to. The UV readings during the trial were recorded at regular intervals and while Day 1 recorded a moderate UV reading and day 2 was low, days 3, 4 and 5 recorded quite intense UV for most of the day. The only deviation from “normal” sunscreen usage was that we were carefully monitored so as not to ingest any. This after all was a trans-dermal study!

So, with this leg of experimental data collecting over what conclusions can be anticipated? Well, the results and discussion will of course take longer to write than this article. The trial was designed to track the fate of nano zinc through skin when applied in a commercially representative sunscreen. While zinc is present in every body, the careful selection of the rare Zinc isotope will make it relatively easy to pick up should any have got into the blood stream or urine. The ratio of the zinc isotopes in any blood samples will also give a quantitative overview of how much zinc made it into the body. The trial design and care of the panelists should enable Professor Gulson and Dr McCall to conclude that any tracer zinc present was absorbed through the skin rather than being ingested.

This trial has been carefully constructed to look for one thing – dermal absorption of nano zinc in a sunscreen base with UV exposure, that was why the tracer zinc was present in both sunscreens the only difference being the particle size. While the sunscreen base was generic, the trial can’t conclude that nanoparticles of zinc will act the same in all sunscreen formulations. There are many different brands of nano zinc – some are specially coated to prevent agglomeration, others are encapsulated for the same reason and yet more are presented in a pre-dispersion. In addition to that, there are many other products that include a nanozinc sunscreen in their formulation. Anti-aging moisturizers are another proposition altogether due to their complex mix of ingredients targeting the cells within the epidermis and the need for a sunscreen to form a film on the surface of the skin.

Like all scientific studies, this one will not answer all of the questions that surround nanotechnology in sunscreens. What it will do though is give a solid basis from which to develop further testing should funding become available. It may also provide a framework from which the cosmetic industry can develop an industry standard test method. After all, the safety of sunscreens is a health issue and consumer confidence and safety remain of paramount importance. It should also be left as food for thought that should the nano zinc turn up in our urine or blood samples, we should not automatically assume that this is going to do harm. Zinc is often taken as a supplement and is essential in many metabolic processes. It is also essential for the health and vitality of skin cells. However, for Zinc to function as an effective sunscreen agent it does need to be present on the surface of the skin and not taken into it– this is another issue and one that formulators may have to grapple with.

I would very much like to thank Professor Gulson and Dr McCall for putting time, funding, effort and passion into this project and allowing me to be a part of it. Consumers want two things from their sunscreens: efficacy and safety and while the individual ingredient manufacturers have assured us of their nano-ingredients credentials and sunscreen manufacturers comply and often exceed current SPF standards, this publicly funded and managed research makes the information available to the general public. Long live publicly funded science I say!

Amanda Foxon-Hill

Realize Beauty.

Our relationship with the sun has soured a little over the years. We probably all know of someone who has had a skin cancer or a troublesome mole removed, suffered from sunburn or got itchy with heat rash. The shrinking of the ozone layer, the march of global warming, and the invention of the bikini and beach volleyball is all against us (or so it would seem). So, where do we stand and what can we do to enable us to take our place under the sun?
We take a quick look at the world of sunscreens through the eyes of a planet savvy beach bum who wants nothing less than to save the planet one wave at a time. Let’s look at the good, the bad and the Naked!

The Good:
The good news is that sunscreens are pretty safe (for us) as long as they are used as directed – getting your mate to apply a bit as you race off into the surf is therefore, not ideal! You must always:
• Make sure the product is in date (check on bottle) and also be aware that product that is left out in the hot sun or back of a car is going to age more quickly than one kept in your cupboard at home.
• You need 35ml of sunscreen for the average adult. That is just over one shot glass full (not the best thing to take to the beach though!)
• Apply the cream at least 20 minutes before going out into the sun. This isn’t to give you enough time to down a smoothie and tofu burger, it is to allow for the cream to settle onto the skin evenly.
• Before you go out in the sun re-apply! This will help you to ensure that no bits got missed.
• Make sure that you use a product that is right for your purpose and skin – Do you need water resistance. How long are you going between applications? What colour is your un-tanned skin? What will you be wearing? What time of day will you be out? If in doubt go for a higher SPF.
There are wide ranges of sunscreens available to suit all skin types and skin personalities. Sunscreens generally work one of two ways physically or chemically. Here is a quick lesson!
Inorganic Sunscreens.
These contain active ingredients such as Zinc Oxide and/ or Titanium Dioxide. These actives work by coating your skin like paint. They sit on the top and act as a shield (which can be visible or invisible depending on particle size) reflecting the sun’s rays away from your skin. These ingredients are often blasted down into nanoparticles to enable the formulation of clear and high SPF sun lotions. While the safety of nanotechnology as a whole is being researched and debated at a global level, there is currently no evidence that nano Zinc Oxide or Titanium Dioxide as used in sunscreens causes any long-term health or environmental damage.

Organic Sunscreens
These contain a wide range of actives – usually the ones with the long names such as ethylhexyl methoxy cimmamate, benzophenone-3 and 4-methylbenzylidene-camphor, Avobenzone and more. These transform the Ultra Violet, skin-penetrating rays of the sun into heat before they can penetrate the skin. Some chemical magic!
The Bad.
Some evidence exists about the negative effects that certain sunscreen actives are having on and in the environment. Some have been linked to coral bleaching, some have been shown to have estrogenic effects through the food chain and some have been linked to increased skin sensitivity in users. The actives most commonly found in the bad books are the inorganic Titanium Dioxide and from the Organic family Benzophenone’s, PABA derivatives, 4-Methyldibenzylcamphor and avobenzone. The main concern being raised by some commentators comes from the reaction that happens between the active and the sun…..
For an organic sunscreen active to work it needs to be able to absorb UV and once absorbed it needs to do something with it. All organic’s work by transferring the energy from the suns UV rays into a mixture of heat, florescence and a photochemical reaction. The photochemical reaction is just another way of saying that a change happens to the chemical because UV is present. Organic sunscreen actives have been designed to react (or change) in the presence of UV light. If they didn’t, they would have no ability to transform UV radiation, leading to no real SPF benefit.
Further to the above, some commentators raise concerns by saying that the above sun filter chemicals break down into smaller, more reactive molecules and cause DNA damage. While it is true that the above chemicals are photoactive (as they need to be, see above), causing DNA damage is a different matter. There is plenty of evidence that links UV radiation to DNA damage, the first signs of it being the reddening of the skin produced from sitting uncovered on the beach for too long. Sunscreens are developed and tested rigorously under TGA guidelines (for Australia) to ensure that the formulation (or recipe) protects the sun from UV radiation for a designated period. While some individual ingredients may be more susceptible than others to unhelpful UV reactions, these factors are considered and corrected for in the product development stage.
Sunscreen developers have found numerous ways to stabilize their products. Actives can be encapsulated to protect them or can be formulated alongside stabilizing agents, which boost the formulations UV tolerance. More recently new actives have been developed which are inherently more stable to the sun’s rays while still giving great UV performance – while that is some comfort for us beach going humans, what does it mean for the environment?
The long-term implications of these chemicals are still being studied and it will take many more years to fully evaluate the environmental and health affects relating to them. This delay is not due to a lack of interest or impetus, it is driven by the complex nature of our relationship with the products and the costs involved in doing these tests thoroughly and independently – a government responsibility perhaps?
Sunscreens contain many ingredients, each formulation is slightly different, each person’s body is unique and how we, as individuals use the products vary enormously. Environmentally we have even more variables to consider including things like soil type, tidal flows, other likely contamination sources and weather. While sunscreens are subjected to, some of the most stringent testing of any personal care product and are the subject of ongoing review both nationally and internationally, it is almost impossible to know everything about them.
This uncertainty has lead to many choosing to take yourself out of the loop – just in case! You can do this by opting for sunscreens that contain only Zinc or stabilised titanium as an active.
The Naked.
Is it all too hard, too risky and too sticky for you? Want chemical free? Naked? Well, going naked is OK as long as you engage your brain. Your skin is well adapted to life on this planet and while we may have migrated to places that suit our temperament better than our coat we can still get by as long as we pay attention to what our body is telling us!
Going chemical free is technically impossible on this planet as we live in a chemical soup, some naturally occurring and some manmade. (Chemistry is only one of the many scientific languages, for describing our world(s). However, we can embrace what nature has given us seeking out products who’s SPF is boosted by natural ingredients such as Shea butter (a physical absorber) and plant based polyphenols (anti-oxidants that work chemically). In addition to that, we can boost our skin’s natural protecting ability through good nutrition and hydration to give us the best chance possible of enjoying a long and fruitful relationship with the sun. The sun is there to be enjoyed, just take it one ray at a time.
A Final Thought.
Life is by its very essence risky and there will always be a risk/benefit ratio. Let it be you that controls that benefit and that risk.

Amanda Foxon-Hill
The Naked Sunscreen.