Sunday, July 5, 2009

Please do not make your own sunscreen!

Raymond forwarded me this link on Instructables - Homemade Sunscreen - and I have to rant about it!

Please don't think me bitter or mean! Someone eager to make lotion will try this and be disappointed and never try it again, and they've lost out on the joys we have found! Or they'll get a horrible sunburn. Or get covered in some kind of hideous bacteria growing in the mixture. I am very passionate about this topic - it's easy to find good instructions for making products, so why pass along misinformation?

I've tinkered with the idea of making my own sunscreen - I have all the ingredients and Raymond has vitiligo, so it would save us a fortune every summer - but there's no way I would know if it were effective, and who wants to be the test subject when the possibility of agonizing sunburn-y pain could be the result?

But I'm going to put that aside for now and move on to the other bits that are bothering me.

The recipe suggests using 8 ounces (240 grams) of carrier oil, 1 oz (30 grams) e-wax, and just under an ounce of titanium dioxide (30 grams). So we have 10 ounces with 10% being e-wax. There is no water in this recipe. So why the e-wax? And why so much? The explanation is that it makes it why not use a butter? E-wax is really not relevant in a non-water based product, unless it's something like an anhydrous sugar scrub or body bar you want to turn into a lotion when you're in the shower.

If you really wanted to make this product - which I do not suggest, and note that you do it at your own peril - then why not a lotion bar? Or what about some nice oils with a little butter and maybe a little wax thrown in to make it thicker? Or a whipped butter? There are many ways to thicken an oil with waxes and butters: E-wax would be one of my last choices!

And please do not use citrus based essential oils in products meant to be worn in the sun. They will make you photo sensitive, leading to pain, misery, and a lot of "oh why did I go in the sun today" kind of moaning! If you must have a citrus based fragrance in your products, consider using a fragrance oil that won't make you sun sensitive. Lavender is supposed to be soothing for apres sun exposure.

Then this poster links to a site on how to make your lotions last more than 3 months. You cannot make lotions in 15 minutes - the heat and hold process takes at least 20 minutes, and you need to take time to get the ingredients up to temperature - and preservatives are necessary. (You can get away without preservatives in an anhydrous recipe, but I always suggest using Vitamin E to retard rancidity). She notes you don't have to follow "complicated industry guidelines of manufacturing" to increase the shelf life of your products. Those guidelines are there for a reason. Few of us can afford to sterilize our equipment, but taking the time to heat and hold, using distilled water, and preserving well isn't a luxury; it's a necessity so we know our products are safe!

Making lotion isn't rocket science (it's cosmetic science!) and you don't need a complicated recipe to make one. (Click to see my post on Lotions: Is it a good recipe?) The advice against making your own sunscreen is about efficacy, and we have no way to test that at home. The advice for good manufacturing practices is about keeping ourselves, our loved ones, and possibly customers safe and not infected with icky things that can grow in unpreserved lotions.

If you want to try a zinc oxide cream - very nice if you've had a little too much fun in the sun - may I suggest this recipe from Voyageur? (Scroll down to see the recipe.) I've used it for soothing various problems and I like it! I did tweak mine to include 10% aloe vera - good for post sun exposure - and more hydrolyzed protein (2% instead of 0.6%). I also included 2% panthenol - again, good for damaged skin. Feel free to switch the stearic acid for cetyl alcohol for a slightly less thick but more glide-y product.

And invest in some good sunscreen. Yeah, it's going to cost you money, but better money out of pocket today than sunburn pain tomorrow or skin cancer in the future.

Thus endeth the rant...


Unknown said...

Hi there!
Just dropping in from the Dish. You are right and sunscreen is not anything we should mess with. No worries about the other person, I listen to you first and when I post on the Dish, I always wait to see what you have to say.

Celene said...

Sunscreen is nothing to play with at home. On my 40th birthday, a surgeon dug out a piece of flesh about the size of a lemon from my rib cage, because I had a kind of melanoma. I was fortunate that a wide excision was curative. I wonder who believes in this sort of thing, uses it, and gets bad news. Melanoma is definitely related to exposure to sun, and our health and lives are not something with which we should play mad scientist, much less advocate others to do as well.

judymoody said...

My dissertation adviser died about a year ago from melanoma. I prefer to leave sunscreen production to the experts. There's a reason its manufacture is so tightly regulated.

Anonymous said...

What if I don't like the ingredients of a sunscreen? What if it contains citrus oils? What if I think that a sunscreen that is acceptable could be better with more antioxidant extracts included?
I always use zinc oxide-based sunscreens, but often I find that I don't like how heavy and oily they are. Also happened that I found many sunscreens that seemed to be packed with great ingredients but, oh no! they have citrus oils added. Other times I find relatively nice sunscreens but I think that might be good if they just have some good antioxidant ingredients included to make them even better. I'm always in the hunt for the perfect zinc oxide sunscreen, but I couldn't find it yet, I personally believe that there's no good sunscreen out there, at least not for me and I always think that I can do it better. I also think is not hard adding to a properly formulated and preserved base some zinc oxide. I haven't done it yet, but I will do it soon at my own risk, and I'll include some green tea, rooibos tea, sea buckthorn, rosehip, pomegranate, cocoa, maybe a little caffeine and probably some color to not have to deal with ghostly-white face.

Susan Barclay-Nichols said...

I don't know what to say, Anonymous. I've already explained at length the dangers of making our own, and you still want to make it? Then go ahead. More experienced formulators than you are terrified of the idea, but if you want to make it, then make it. Just don't share it with anyone because it's just cruel to offer them something that might not work.

As an aside, do you know if sunscreen ingredients and anti-oxidants play nicely? Do you know which emulsifiers you can and can't use with sunscreen ingredients? Do you know which preservatives you can use without deactivating the sunscreen ingredients? Do you know how much sunscreen protection you'll get from zinc oxide? If you can't answer these questions adequately, I wouldn't recommend making your own. But I think all of this has fallen on deaf ears, anyway, as you're going to do what you are going to do. The sad thing is that someone could get really hurt and you won't know for years that you were the one who caused it.

Evik said...

Dear Susan,

I tried to understand your points on not trying to produce your own sunscreens, and have a hard time with some.
Probably I am missing something (as usual), I am just thinking....

With Internet, it is relatively easy to get a good browse in scientific journals discussing for example the efficacy of zinc oxide in sunscreens and yes, also find basic formulas - often in the papers comparing different formulations. There you go, having also the tests.

The same apply for all the rest - compatibility with preservatives, other antioxidants etc.

Sure, it takes a lot of time, searching journals, books, patents... but it is not impossible!

And yet here you are, an expert with years in cosmetic formulations, saying that it is impossible to find all this information i.e. for mineral sunscreens (this is the group I would focus on). That just doesn't make sense to me.

I wouldn't say don't try. I would say make a thorough research on this subject first. I guess this is also how you have built your expertise in the domain. Or not?

Susan Barclay-Nichols said...

Hi Evik. By all means, study the topic! It's a fascinating topic, indeed, and there is much to learn. I have a really good textbook on the topic, and you could go out and buy that or another like it, read all the studies you can, find some beginners' formulations, and enjoy the research. Don't trust everything you read on the 'net - get good quality, well researched material and learn all you can. But that isn't the issue.

The issue is that you can't test it to ensure it works. I could go into my workshop and make a product that looks like a sunscreen with physical and chemical blockers, but it's not a sunscreen until we know how well it works. How do we test if it works? Do we put it on someone we love and send them out into the sun? If they burn, we know it doesn't work. If they don't burn, we don't know anything as there are so many variables as to why our skin might not burn. In the meantime, we're putting someone's health at risk, and that's not okay.

Sunscreens in Canada require a drug identification number because they're considered drugs. We can't make drugs at home because they require testing and studies and everything else that a drug needs. Making a sunscreen is more like making a cold medication than making a lotion in the eyes of Health Canada.

Please read this updated post on sunscreen to see more about why you shouldn't make your own sunscreen!

There isn't an argument anyone can make that will convince me that we can make an effective product at home, so I think I'd like to stop discussing this topic now. I've offered all the information I can. If you - the everyone you, not just you, Evik - want to make your own sunscreen, I've done all I can to warn you against it. I'm done with this topic.

Anonymous said...

Thanks. Great article. And yes, a strange recipe. I have self tested a suncream that I make using butter/wax/oil combo and 22% non nano zinc oxide. Living in the French Alps and skiing at 1900m works but only if I follow the rules of using physical mineral suncream ie apply every hour and layer it. Dispersion is an issue since zinc isnt oil soluble. Having said all that, I completely agree that sun protection is not something to mess with...and as the EU have very strict regulations, my formula will he going to a laboratory in London for analysis and efficacy testing.