Bath Bombs: What Ingredients To Use And What Not To Use...
Let's talk about bath bombs (and fizzies and all the bubbly things we love to put in our tubs and soak in). Did you know that all of these products are considered cosmetics and in turn are governed by the laws of the FDA? Yes, if you are making bath bombs and selling them, there are rules and regulations you have to follow to be legally compliant. The FDA has standards on what ingredients are acceptable to use in cosmetics and bath bombs. I am constantly getting asked about ingredients, especially colorants, that are safe for use in bath bombs. Let's talk about ingredients.
The most basic ingredients in a bath bomb are going to be baking soda and citric acid. Depending on the ratio of ingredients you are using will determine how much it effects the pH of your water. Have hard water? You could add things like corn starch, tapioca starch, or arrow root powder to give the water a silkier feel. Most makers will add one of these powders to allow the water to have a better skin feel as the baking soda helps to soften the water and the addition of one of these powders will allow the silkiness to come through (think about how body powder feels on the skin).
Next, most bath bombs have some type of oil, butter, or both. Oils and butters add a wonderful moisturizing element to the water. A lot of makers will then add a solubilizer such as polysorbate 20, polysorbate 80, or polysugamulse D9 to allow the oils to solubilize in the water and not leave a big floating pool of oil that sticks to the sides of the tub and makes it super slippery when trying to get in and out. We should not be using things like borax to solubilize oils in bath bombs. If you don't care for polysorbate, polysugamulse D9 is a polysorbate replacement that is naturally derived from sugar. (you can find it here- https://missdoyles.com/collections/ingredients-making-magic/products/poly-suga-mulse-d9 ).
Salts are another great additive for your bath bomb. Epsom salts bring the amazing powers of magnesium sulfate to your bath and are a wonderful addition to a bath bomb. Himalayan pink salt is also great with its mineral content to add to bath bombs. Try to steer clear of Dead Sea salt in your bath bombs as they are extremely hydroscopic (water loving) and will pull moisture into your bomb which will cause activation.
Do you want your bomb to foam and fizz? Adding a gentle surfactant in a small amount can give you a lot of foaming action. We regularly use SLSA (sodium lauryl sulfoacetate), SCI (sodium cocoyl istheionate), and Suganate 160 (Sodium Laurylglucosides Hydroxypropylsulfonate). There are many other surfactants you can use, but these are the ones we personally use in our business.
There are a host of other additives you can add to bath bombs to make the skin feel amazing and to add label appeal. We regularly use goat milk powder, colloidal oatmeal, and other powdered additives (milks, aloe, etc). Make sure when adding these items that they are approved for use in cosmetics. These things not only leave your skin feeling soft and moisturized, but they garner the attention of customers.
Fragrance is really a personal preference when it comes to making bath bombs. In our time making bath bombs, we have found that some fragrances work wonderfully while others change scent or lose their fragrance over time. I have found that essential oils are definitely more apt to lose their potency over time in bath bombs. Make sure you test your fragrances and essential oils in small batches and check them over time to see if they lose their potency or cause a color change in your bath bomb (yes, vanillin can do that to bath bombs sometimes). You can get some of my favorite fragrance and essential oils here https://www.muddysoapco.com/product-category/muddy/fragrance-oils/
Now its time for the big one.... Colorants! There are always a lot of questions about what colors can and can't be used in bath bombs. First and foremost, food coloring is not an FDA approved colorant for bath bombs. Please... I am begging you, do not use food coloring in your bath bombs. You will ruin people's bath tubs, stain their skin, and you will be breaking the law. Just don't. Don't risk your business over food coloring. Now that I have that out of my system, lets talk about what you can use. In bath bomb making, we can use batch certified lakes and dyes. Lakes are oil soluble and require a solubilizer like polysorbate or polysugamulse to help disperse it through the water. It does not need to be bloomed because it is already bloomed in an aluminum salt substrate (not the harmful aluminum banned from other uses in bath bombs). Lakes and dyes must be batch certified to be used in bath bombs.
Dyes are pure pigment and will need to be bloomed before using. They are very concentrated so be cognizant of the amount you will be using to ensure you aren't dying people's skin and tubs. Always make sure you are buying from a reputable source that can give you documentation on the certification of the lakes and dyes you are purchasing.
Micas are exempt but, and this is a big but, you cannot use any mica that has chromium green or ultramarine blue. Check the INCI on your micas. Most companies will list whether a mica is safe for lips and eyes. If it is listed as general use only and not safe for lips and eyes, it is a no go in your bath bombs. Micas will not tint the water the way dyes and lakes do and can sometimes stick to the side of the tub, even with the use of a solubilizer.
Also, glitter is not an approved for bath bombs. If a glitter has aluminum in it, you cannot use it in a bath bomb. You can use Fluorphlogopite based mica to add sparkle to your bath bombs.
Making bath bombs is a great way to add a product to your line, but make sure you are following the rules and regulations. Also, if you are selling any type of bath and body product, you should be carrying product liability insurance. For more information about bath bomb making and rules and regulations for cosmetics, go to http://unique-makers.teachable.com and join The Unique Makers.