Read the Label: Sunscreens
Rather than slather liberal amounts of chemicals on our bodies and faces with sun creams and other cosmetics, Pat Thomas suggests a little sun exposure might do us good.
Sunscreens protect the skin from the sun’s harmful UV rays. They are beneficial. They are desirable. They are necessary. Or so we are told. So why is there so much evidence suggesting that in fact their risks drastically outweigh their benefits?
There are two basic types of creams available on the market today: chemical sunscreens, which act like sponges, absorbing UV light and keeping it from penetrating the skin, and mineral sunblocks, which reflect or scatter light in both the visible and UV spectrum. Both are associated with skin irritation.
Sunscreening chemicals are absorbed into the skin and sunblocks sit on the skin’s surface and act like tiny mirrors reflecting UV light away from the skin. Chemical sunscreens – which are by far the most widely used in commercial products – have some major drawbacks:
- They are more easily absorbed into the skin
- They are powerful free radical generators. Free radicals are the unpredictable molecules which can cause cellular damage and the kind of changes that lead to skin damage
- They often have strong hormone disrupting effects, often mimicking the effects of estrogen in the body
- They are synthetic chemicals that are alien to the human body and in some cases can accumulate in body fat stores. The human body is well adapted to detoxify biological substances that it has been exposedto for over tens of millions of years. But it has often has difficulty removing new and non-biological compounds such as DDT, Dioxin, PCBs – and chemical sunscreens.
Hormone disruption
The estrogenic properties of sunscreening chemicals are particularly worrying, because chemicals that are estrogenic can fool the body into believing they are natural hormones. This can cause reproductive and menstrual problems and may be a trigger for estrogen dependent cancers of the breast, endometrium, ovaries and prostate.
In the last few years a series of disturbing laboratory and environmental studies have shown just how widespread the problem is in sunscreens. In one Swiss study in 2001, six frequently used UVA and UVB sunscreens – benzophenone-3 (Bp-3), homosalate (HMS), 3. 4-methylbenzylidene camphor (4-MBC), 4. octyl-methoxycinnamate (OMC), octyl-dimethyl-PABA (OD-PABA), butyl-methoxydibenzoylmethane (B-MDM) – were analysed for their estrogenic potential.
All but the BMDM were found to be estrogenic. Sun creams can also contain preservatives such as parabens, which are also estrogenic. Since mixtures of different estrogens are known to have a more powerful effect on body tissues than single substances, it is worth asking why no manufacturer has bothered to study the cumulative health effects in humans of applying sun creams on a daily basis.
We know what happens in fish however.
Recent data shows that male hornyhead turbot and English sole feeding near the outfalls on the California coast are being feminised and oxybenzone, a chemical found in sun creams, is the likely culprit. Two-thirds of turbot and sole were growing ovary tissue in their testes.
European data shows that other sunscreen chemicals – octocrylene and 4-methylbenzylidene camphor – are also building up alarmingly in the fish population and causing gender-bending effects.
Worse, we don’t just put them on our skin, we wash them down the drain, and then ingest them in drinking water and in the foods we eat. And as the sunscreen becomes de rigueur in cosmetics of all types, we don’t just apply them during the heat of the summer, we apply them all year round, on faces and bodies, men, women and babies and even at night in so-called ‘night creams’.
Nanotechnology
Because we apply them so ubiquitously, many healthcare gurus are now recommending that mineral sunblocks, which sit on the skin, may be safer than chemicals that are absorbed into the skin. But even these so-called safer mineral sunblocks have become the subject of controversy. Today many creams use nanoparticles of zinc oxide and titanium dioxide.
Nano-sized sunblocks spread more easily and appear transparent on the skin and this has helped manufacturers get round the aesthetic problem of the thick white pastes of past eras. The problem is that evidence of their safety is sorely lacking. Some manufacturers boast formulations containing zinc oxide nanoparticles as small as the tiniest known viruses.
On the one hand, this may seem like a technological breakthrough, but cast in another light it is highly alarming. Nanoparticles are known, because of their size, to behave in strange and unpredictable ways since, at the nanoscale, quantum physics can take over, and the Newtonian physics of everyday life becomes less dominant. Particles of that size can go anywhere they please.
Should they get into the body, for instance, they bypass the entire immune system and pass through the blood-brain barrier that protects the brain. In 2004, the UK report Nanoscience and Nanotechnologies: Opportunities and Uncertainties recommended nanoparticles be treated as ‘new chemicals’ under UK and European legislation.
Doing so would trigger appropriate safety tests, and require that nanoparticles be approved by an independent safety committee before they were permitted for use in consumer products such as cosmetics.
Manufacturers have strenuously resisted this, especially since more than 200 nanoparticle-containing products are already on the shelves.
Natural alternatives?
While several sun creams on the market boast natural ingredients, it is important to read the label to see what’s really in them. It is impossible to make an entirely natural sun cream.
Manufacturers must use either chemical sunscreen or mineral sunblock – often they use a combination of both. So-called natural sun creams will contain as few of these ingredients as possible to achieve the desired sun protection factor (SPF), but they will always contain them.
In addition, they may contain skin protection co-factors such as vitamins C and E, antioxidants like green tea, shea butter, which has a natural though mild sunscreening effect, and emollients such as cocoa butter and emu oil.
These natural ingredients are good but they are also, in the end, compromises. Given the huge benefits of regular sun exposure and the as yet unquantified risks of sunscreens, it might be worth asking yourself if it isn’t smarter to get out and enjoy the sun unprotected for short periods each day, and cover up or seek out the shade for the rest of the time.
Sidebar: What you can do
1 Look at the labels of your favourite products. Do any of them contain the following chemicals?
- Octyl methoxycinnamate (OMC)
- Octocrylene
- Ethylhexyl pMethoxycinnamate
- Octyl salicytate (OCS)
- Homosalate
- Neo-homosalate
- Octyl salicylate
- Para-aminobenzoic acid (PABA)
- Ethyl dihydroxypropyl PABA
- Octyl dimethyl PABA
- Glyceryl PABA
- Padimate-O
- Oxybenzone
- Avobenzone
- Dioxybenzone
- Sulisbenzone
- Methyl anthranilate
- Digalloyl trioleate
- Zinc oxide
- Titanium dioxide
2 If so, please photocopy these pages, tick the boxes of the worrying chemicals you have found on your sun cream label and write to the manufacturer’s customer services department, asking them why they are using these chemicals in their products and what proof they have that their sun creams actually prevent skin ageing and diseases like skin cancer. In particular, ask them to justify the use of nanoparticles in their products, given the total lack of safety data.
3 Ask the manufacturer to send a copy of their reply to the Ecologist, Unit 18 Chelsea Wharf, 15 Lots Rd, London SW10 0QJ or, failing that, pass the reply you do get on to us, as we will be monitoring all feedback for future investigations and campaigns. Thank you!
- This article first appeared in the June 2006 edition of the Ecologist
