Can bath bombs explode when heated by fire?

What is a bath bomb?

If you don’t know what a bath bomb is, it’s essentially a ball made primarily from sodium bicarbonate (baking soda), which is combined with additional ingredients such as essential oils, fragrances, and other additives.
These balls are then dropped into the tub filled with hot water, releasing an amazing aroma of essential oils, as well as helping to give your skin a spa-like treatment when you soak in the tub afterwards.

Whether bath bombs can explode when heated

Bath bombs are generally safe to use and do not pose a significant risk of explosion when exposed to heat. While heat may cause them to melt or lose their shape, it is unlikely to cause an explosion. As with any product, it is important to follow the manufacturer's instructions for use and handle bath bombs with care to ensure a safe and enjoyable experience.

natural bath bomb Recipe

Baking soda – the foundation of this recipe.  Combined with citric acid it provokes the fizzing action.
Citric acid – the rarer ingredient in this recipe that many don’t have (you’ll have to buy some).  The fizzy reaction is like swimming in champagne.
Cornstarch gives us the silky feeling that we all love in bath bombs.  In this recipe, we typically use organic cornstarch powder.  Arrowroot works as well but does not provide a finished product as silky.
Oil, salt, and liquid – these are all very flexible and you can choose any mix.
Oil – pick a basic olive oil, almond oil, or coconut oil.
Salt – stick to basic salt or add Epsom salt or another favorite salt choice.
Liquid – simple water works, but herbal witch hazel is also useful for extra skin soothing.

Add scents and colors with natural additives, colorants, and essential oils.