How dangerous is lye?

Lye has the potential to be very damaging, but I would like to contextualize that within your day-to-day life and dangers you regularly face. A lot of the reading you’ll do on NaOH (sodium hydroxide)/KOH (potassium hydroxide) will have you thinking it is the most dangerous thing you’ve ever handled by a factor of 10, which will likely make you very afraid of it, and nervous whenever you handle it. When you’re afraid and nervous you don’t work very well. Your hands might shake. You might be more likely to freak out if you think something might be going wrong, compounding the problem. I would like to argue that you do not need to be afraid of lye. You need to respect it.

I would like to draw a parallel between a concentrated lye solution and boiling water. Both have the potential to do a lot of damage to you. I’m quite familiar with the boiling water side of this as I once sustained a second-degree burn on my stomach from a cup of just-brewed tea. It’s no laughing matter. Photos I’ve seen of serious lye injuries look a lot like my scalding burn. Multiple layers of skin instantaneously blasted away, leaving the remaining skin raw and seriously damaged. OUCH.

Both boiling water and concentrated lye solutions are dangerous and should be respected and treated with care. However, when most people handle boiling water they are not afraid of it. They are well aware that they should not stick their hands in it, and should take great care to avoid spills, but they are not so terrified of it that they have adrenaline coursing through their veins whenever they have to work with it. Treat lye water with the same level of respect you’d treat boiling water, and you will be ok. Be calm, be careful, but do not get so worked up with fear that you’re quaking in your boots.

If you think treating lye water with the same level of respect that you’d give boiling water is encouraging lax lye safety… I don’t know what to say to that. I suppose I would encourage you to treat boiling water with more respect if that’s the case.

The concentrated lye water stage is the most dangerous part of making soap. This is the stage where you should be wearing gloves, eye protection, and an apron—especially if you are new to soap making. This is because this is the stage where you will sustain the most damage if anything goes very wrong. Start with all the protective equipment, familiarize yourself with the process, and don’t be an idiot. But also don’t be terrified.

Once the lye water has been blended into your fats, the danger factor goes down significantly. This is because the lye is now diluted in a bunch of oils and fats. As with all things, the dose makes the poison. Raw soap batter is nowhere near as dangerous as a concentrated lye solution because it is nowhere near as concentrated. Is it still very basic and caustic? Yes. But we are not in “instantly blasting off your skin” territory anymore. If soap batter ends up on your skin, you will likely not even notice for a few minutes. When you do, it’ll itch, you’ll wash it off with water, and that’s that. Side note: don’t use vinegar for this; it’ll react with the lye and cause extra damage. Just use lots of water.

I’ve heard from some experienced soap makers that they no longer wear gloves for this raw soap batter stage as they find gloves negatively impact their grip and made them more likely to slip or spill. They also all stated that this was a personal choice for them. I sometimes don’t wear gloves for this stage anymore, either, but that is definitely a personal choice borne from my experience with contact with raw soap batter. If given the choice of having an accident with one or the other, I would choose diluted raw soap batter over boiling water any day. Many other soapers said they still wear gloves all the way through because they prefer gloves to the raw soap itch, or because they’re particularly klutzy or messy. When you have years of experience behind making this call, I say go for it. This is you. Your body. Your hands. Your risk assessment. In my personal experience, the risk at this stage is fairly low, especially if you are being careful.

In the end, it is best for you to wear safety gear, for those just in case moments. Especially goggles. Your eyes are much harder to wash than your arms, and they don’t heal up nearly as well. However, I don’t want you to be afraid of lye. I want you to respect it. Fear is not productive or conducive to good decision making. Fear leads to the jitters, and jitters lead to spills. Don’t be afraid. Be respectful. Ensure your working area is clear of tiny intruders (aka children & pets). Don’t be an idiot. But don’t be terrified, either.

Posted in: Soap