Sustainable Sunscreen: Why Homemade Doesn't Work & What Natural, Reef-Safe Ones Do

Reusable Nation - Environmentally friendly sunscreen

Is there such a things as zero waste sunscreen? You can DIY it, but is it safe? We tried to find sunscreen that is both eco-friendly and effective.

Sunscreen has been around since the 1930s. It was invented by Swiss chemistry student, Franz Greiter after he suffered sunburn while climbing Mount Piz Buin. It has since become an essential product for anyone entering the sun, not only to protect against sunburn, but to protect against cancer as well - especially if you live in Australia like us!


Why the move towards homemade sunscreen?

Commercial sunscreen products have started being questioned and natural sunscreens are becoming popular, both ones you can buy and ones you can make yourself.

People are choosing homemade sunscreen for a number of reasons - to avoid chemicals in sunscreen perceived as toxic to humans, to avoid chemicals in sunscreen that are toxic to reefs and marine life, and/or to avoid the plastic tubes regular sunscreen comes in.

We started investigating homemade sunscreen as we wanted to make the switch for the last two reasons.

But first, are the chemicals in sunscreen toxic to humans?

According to Australia’s Cancer Council, no: “given there has been many rigorous scientific reviews, there is now very strong evidence that the list of commonly used active ingredients used in sunscreen do not pose a concern for human health”.

We still did further research on some of the ingredients that we have been warned against and have summed it up below.

Titanium dioxide and zinc oxide nanoparticles

The Therapeutic Goods Administration (TGA), which regulates sunscreen, has conducted a literature review on the safety of titanium dioxide and zinc oxide nanoparticles in sunscreens. It concludes that “neither are likely to cause harm when used as ingredients in sunscreens and when sunscreens are used as directed”.
Cancer Council has also been monitoring research on nanoparticles used in sunscreen and believes that they do not pose a risk.

Choice has also looked into these nanoparticles and found that “there's no known health risk from these nanoparticles and you can safely use sunscreens that contain them”.

The results of its research are that “zinc oxide and titanium dioxide nanoparticles aren't absorbed through the skin into the bloodstream and, in the event that they do get into the bloodstream, via accidentally eating or inhaling the particles, say, the body's immune system can deal with them effectively (for zinc oxide at least)”.

Oxybenzone and octinoxate

There is also no evidence of any chemicals approved for use in Australian sunscreens disrupting the endocrine system, according to Cancer Council.

It says that while “online campaigners based in the US and Europe have expressed concerns that sunscreen may contain endocrine disrupting chemicals, such as oxybenzone and octinoxate”, the TGA has reported that there is “insufficient evidence to support the claim that chemicals in sunscreen interfere with the endocrine system in humans”.

It adds that “the endocrine disruption studies were based on the ingestion (swallowing) of the chemicals, rather than their application on the skin, which results in much lower absorption into the body”.

Environmental Working Group (EWG) says that there are laboratory studies that indicate that some chemical UV filters may mimic hormones. However, scientists admit that the evidence from these studies is not 100 percent conclusive and EWG says according to experts, “more sensitive tests are needed to determine whether sunscreen chemical ingredients pose risks to frequent users”.

If you are worried about these ingredients being in your sunscreen, they can be avoided by picking a sunscreen that uses physical blockers such as zinc oxide or titanium dioxide.

Are the chemicals in sunscreen toxic to reefs and marine life?

A study done this year that was published in the New Journal of the American Academy of Dermatology found no demonstrable harmful effects in humans from chemical sunscreen ingredients, but it did find emerging evidence that it could enter the water supply and affect marine life, including fish and coral reefs”.

One study found that “sunscreens cause the rapid and complete bleaching of hard corals, even at extremely low concentrations” and sunscreens containing oxybenzone have been banned in Hawaii.

The paper in the New Journal of the American Academy of Dermatology recommends that “those who are concerned about the potential effects of chemical sunscreen ingredients on the environment can opt for a physical sunscreen containing the active ingredients zinc oxide or titanium dioxide”.

EWG also believes that mineral sunscreens are a better option, with these commonly rating better than chemical sunscreens in its sunscreen database.

Haereticus Environmental Laboratory, which studies the effects of sunscreen on coral reefs, has a list of chemicals and attributes in personal care products such as sunscreen lotions and sprays that can have a detrimental effect on the existence of aquatic and marine ecosystems.

Its list includes:

  • any form of microplastic sphere or beads

  • any nanoparticles like zinc oxide or titanium dioxide

  • oxybenzone

  • octinoxate

  • 4-methylbenzylidene camphor

  • octocrylene

  • para-aminobenzoic acid (PABA)

  • methyl paraben

  • ethyl paraben

  • propyl paraben

  • butyl paraben

  • benzyl paraben

  • triclosan

You’ll notice that zinc oxide and titanium dioxide are on the list, but this refers to nano versions only - mineral sunblocks including zinc oxide and titanium dioxide that are non-nano in size are considered safe.

Why homemade sunscreens can't be trusted

So the best way to avoid all these chemicals is to make my own sunscreen at home? Unfortunately, no. It would be great if we could DIY our own sunscreen and put it in repurposed bottles, but there is no scientific evidence that homemade sunscreen works and you can’t control the SPF, which will likely be very low.

The SPFs of essentials oils are only between one and seven, according to Pharmacognosy Research and coconut oil blocks only an estimated 20 percent of the sun's damaging rays, according to medical practitioners.

The SPF and broad spectrum coverage of the ingredients in homemade sunscreens is not proven and the effectiveness of their formulations are not standardised or verified. Pretty much “anything you read about homemade sunscreen online is based on anecdotal information, not actual research”, according to Consumer Reports.

Although you can buy actual UV-blocking ingredients online, you can’t be sure that they are stable and safely mixed. You’ll be able to tell if it protects you from sunburn, but you won’t know if it is protecting you against exposure to UVA and the future problems that brings until it’s too late.

Cancer Council warns against using any products that “aren’t TGA approved, aren’t actually a sunscreen or are homemade as these products won’t have been properly tested for effectiveness and may not provide proper sun protection”.

Choice agrees, noting that “there's more risk from not using sunscreen than there is from using it, whether or not it contains nanoparticles”.

With statistics like “approximately two in three Australians will be diagnosed with skin cancer by the age of 70” and as “the majority of skin cancers in Australia are caused by exposure to UV radiation in sunlight”, I don’t believe it’s worth the risk.

Natural and reef-safe sunscreens that work

With homemade sunscreens struck off our list, we began searching for a reef-safe sunscreen that works, hoping it would also come in eco-friendly packaging.

As the Cancer Council recommends using an SPF30 or higher sunscreen that is broad spectrum, water resistant and TGA approved, this is what I set out to find. The council says “as long as your sunscreen meets these requirements, what brand or ingredients you choose is up to you”.

How do you know if a sunscreen is TGA approved? Look to see if it complies with AS/NZS 2604:2012. This is specific to Australia. If looking into non-Australian sunscreen products, find out what approvals and standards it needs in the country it is from first, for example Food and Drug Administration (FDA) approved in America and Health Canada in Canada.

You can search on this website to check a sunscreen’s TGA status and its active ingredients.

Not all of the sunscreens you can buy from online stores such as Flora & Fauna, Biome, and The Clean Collective are on the Australian Register of Therapeutic Goods and TGA approved.

Some Australian natural sunscreens we found that are on the Australian Register of Therapeutic Goods are:

Unfortunately, all of these sunscreens come in plastic bottles.

Sunscreen can be found in steel tins and wooden or bamboo pots, but we have not found any TGA-approved natural sunscreens that come in these sorts of eco-friendly, zero waste containers…

***Update: …UNTIL NOW! We have found a TGA-approved natural sunscreen that comes in a metal tin - Sunbutter Sunscreen! It provides broad spectrum protection from UVA and UVB rays, with zinc oxide as its active ingredient. It is free of parabens and does not contain oxybenzone, is palm oil free, vegan, and made in Australia. You’ll find it on Flora & Fauna here.***

If you do buy sunscreen in plastic, make sure you recycle the plastic bottles these sunscreens come in. Depending on the type of plastic it is made from, it could be placed in your regular recycling bin for council to collect or placed in Terracycle's Beauty Box. Always check your council's recycling regulations first. If they can't take it, find a Beauty Box drop-off location here.

How to use natural sunscreen properly

For natural sunscreen to be as effective as it can be, it needs to be applied correctly and a little differently to chemical sunscreen. It also looks a little different on the skin and will leave a white film or cast on the skin.

According to Shop Naturally, it is important to:

  • be generous - you need to make sure that you are fully covered and covered well as mineral sunscreen provides a physical cover,

  • rub it in evenly - mineral sunscreen can take longer to rub in so spend enough time doing this to ensure coverage,

  • apply it at least 20 minutes before going in the sun (as with any sunscreen), and

  • re-apply it every 2 hours or after sweating or swimming or towel drying as the physical barrier it provides deteriorates over time and with water and rubbing.

What sunscreen we’ve decided to go with?

As always, it’s a personal choice whether you use homemade sunscreen or one off supermarket shelves, but it is important to know the facts and to do your research before putting your faith in a particular sunscreen.

For us, our health comes first and that is why we have made the decision to avoid homemade sunscreens and stick with commercial sunscreens.

However, we want to reduce the impact of our sunscreen on the earth as much as possible, so we will only be buying reef-safe sunscreen.

Remember to not rely solely on sunscreen either - don’t spend too much time in the sun, get into the shade, wear a wide hat and sunnies, and don’t be afraid to rock a rashie.

What sunscreen do you use? Have you found any we can add to our reef-safe sunscreens that work list?



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