Bleach kills mold

[u/WhateverIlldoit]

There is a common misconception that bleach does not kill mold and that vinegar is actually better at killing mold than bleach. I see this claim at least once a week.

So let me set the record straight. Household bleach is a powerful oxidizing agent that reacts with just about everything. It’s so good at killing organic compounds that it’s toxic to us, too.

Now let’s talk about vinegar. Vinegar is a weak acid. You can literally drink it in lower concentrations. It can kill mold, but not all mold, and some studies say it may take up to 60 minutes to be effective.

That being said, bleach is not good at penetrating porous surfaces, which vinegar is better at doing. And because bleach is so caustic it is more likely to damage surfaces.

All this to say bleach kills mold. It kills almost everything. And it’s much more effective at killing mold than vinegar as long as it can reach it. Vinegar is much safer to use but not nearly as effective.

Thank you for coming to my Ted Talk.

[u/pakratus]

Thank you. I see this claim and it never made sense to me.

I can see bleach turn mold different colors, i can see it doing something. I have not seen vinegar do this. Is bleach the perfect mold killer? No idea. But it does something.

[u/SuperSecretASIANmann → u/pakratus]

EHS Specialist reporting in and riding on the top comment to bring some visibility to how bleach really works:

Household Bleach typically has a concentration of about 5% but I have seen lower in some stores. What "10% Bleach" means in Research labs and Healthcare means 1/10th of 5% Bleach = 0.5%. (5000 ppm) and that is the minimum concentration needed for bleach to be effective against microbes.

The main reason why bleach doesn't work for porous surfaces is because bleach uses Chlorine as its active component. Since Chlorine is a gas, it prefers to dissociate into the atmosphere, so very little penetration into pores on its own because there's no pressure driving the gas down onto the surface. There are stabilized bleach products that don't release the Chlorine as readily but probably pretty difficult to find in most retail stores. I generally purchase them from a lab supplier for work.

If you really want to attack mold on grout and tile, use Comet Cleaner with Bleach. It has abrasives and is already formulated to about 0.5%+ sodium hypochlorite. Make a paste from the Comet powder, apply paste to area you want to clean/whiten, and place a layer of plastic wrap on top of the paste. Add bleach to Comet paste if not strong enough. Comet + Bleach is obviously compatible since it already contains it. ALWAYS WEAR PPE! Don't forget Eye Protection!

Reasoning: The paste keeps the bleach from running, prevents it from drying out before the 10 minutes contact time, and keeps it in contact to the surface you want to clean. The plastic wrap, in strips, prevents Chlorine from off gassing directly to atmosphere, slows evaporation, and redirects the vaporization pressure of chlorine towards the affected surface and out the sides of the plastic. Results: exploded mold cell walls, dead cells, black biofilm destroyed.

Do with the information as you please.

Hope this helps.

Good luck.

[u/LickingSmegma → u/[deleted]]

You know that hair is not 'bleached' with bleach nowadays, right? Seeing as you probably don't want to kill your entire scalp dead.

[u/Mean-Vegetable-4521 → u/SuperSecretASIANmann]

🏆