Should you use vinegar or bleach on mould?
In Short
- Never mix bleach with any other products as it creates toxic gas that can kill you
- Bleach simply takes the colour out of the fungi, it does not kill the entire plant, it also does not soak into porous surfaces
- Vinegar kills the entire plant
- Both vinegar and bleach damage substrates (such as grout)
- Both bleach and vinegar kill some moulds remediation and mildews, but not others
Bleach is Not a Team Player
Never mix bleach with other cleaning products. Ever. Don’t muck around and find out, but if you mix bleach and ammonia, you make a toxic gas called chloramine that could kill you. ‘Mustard gas’ (phosgene) is a by-product of bleach and ammonia. Bleach and vinegar mixed create chlorine gas, which is also potentially lethal.
If you accidentally create a toxic gas, leave the area immediately, remove all animals and humans. Ventilate thoroughly. Seek medical advice immediately if anyone is struggling to breathe.
Regular use of bleach also is linked to developing COPD (chronic obstructive pulmonary disorder, a lung disease). When possible, avoid using chlorine and opt for less harmful products.
What is Bleach?
Bleach is also known as sodium hypochlorite, with a chemical formula NaOCl. This is essentially sodium (salt, NA), and hypochlorite anion (OCl or ClO).
Chlorine is Cl2. Chlorine is essentially the gas form of bleach (skimming over complex chemistry there, apologies to all chemists).
It is basic/alkaline, with a pH of 11 to 13. This means it’s pretty corrosive. It is found in a range of products such as Exit Mould. It can be antibacterial and antifungal.
What is Vinegar?
Vinegar is a combination of water and acetic acid, made using a fermentation process. First, a yeast feeds on sugar, which ferments into alcohol. This is then exposed to oxygen and a bacteria called acetobacter. Over weeks and months, this forms vinegar.
Balsamic vinegar, for example, is made from fermented grapes, and is left to ferment up to 25 years. White vinegar, which is what you’ll use to clean, is made from fermented grains.
It is acidic, with a pH of 2 to 3. Vinegar has antibacterial, antimicrobial, and antifungal properties.
Should You Use Bleach or Vinegar to Kill Mould?
This is complicated.
- Bleach looks like it’s killed the mould because it disappears upon application. However, it simply takes the colour (melanin) out of the fungi, so you can’t see it any more
- Bleach does not penetrate porous materials, so while it could be effective on a ceramic tile surface, it won’t help with the grout itself, nor with timber or plaster when the roots of the mould travel deep
- Bleach can damage grout and tiles as it erodes and corrodes surfaces- it’s very alkaline
- Bleach works by damaging the mould’s structure and destroying the cells
- It appears that ascetic acid in vinegar works by lowering the pH of the fungi cell and killing it. It kills the whole plant including the roots. However, the melanin stain stays there, so you’ll need to give a good scrub afterwards.
- Vinegar is acidic, so it can damage the surface of things like stone, marble, tiles, and protective finishes/ varnishes on wooden floors over time
- Vinegar is slow acting, so it doesn’t look as effective as bleach
- Vinegar is great as a fabric softener and has an anti-microbial effect on laundry
- All over the internet, it says that vinegar kills 82% of mould. There is no study in existence and appears to be made up. However, it does kill many mould types. Vinegar is effective at treating Penicillium chrysogenum but not Aspergillus fumigatus (with mixed results on other common household moulds).
- The internet also says the mould eats the vinegar and then explodes. This sounds very dramatic but is not true. Don’t believe everything you read on the internet.
The outcome of this is that both bleach and vinegar kill some mould types. Bleach is good at removing the visible signs of mould, but doesn’t actually kill the whole plant. Vinegar kills the entire plant, including the roots.
So what should you use? It depends on the surface.
For example, net curtains can be damaged by bleach, turning them yellow and breaking down fibres. A wash in the machine with regular clothes detergent and a final rinse with white vinegar should do the trick. The, dry it in the sun as sunlight kills bacteria and fungi.
On your tiles, walls, and ceilings, try vinegar. Let it soak for an hour, and then scrub all visible mould off. Sadly, you’ll need to remove any silicon edging with mold on it, as this is not something that can be resolved.
So What DOES Kill Mould?
There are two really effective, safe, products that kill mould. Tea tree oil (and Manuka oil should be effective too), and oil of cloves. These are however both quite expensive, and they can stain/ burn plastic or other substrates. Also, they can affect asthmatics and may not be safe for use around animals.
So, that brings us full circle around to vinegar. The best solution in terms of lung health and effectiveness is eight parts vinegar to two parts water, a microfibre cloth, wet the area, leave for an hour, and then a lot of elbow grease. Drying things outside in the full sun is super helpful, but this isn’t possible for ceilings, walls, and grouting; simply let things dry as much as possible.
If there’s still visible mould, after copious washing to remove vinegar remnants so you don’t kill yourself with chlorine gas, try application of bleach, which will remove the visible evidence of mould.
And if the problem is truly bad, then contact professional mould cleaners. They’ll take care of the problem for you.
