Does Vinegar Kill Mold? What the Studies Found, and Its Limits

Cleaning brands say vinegar kills most mold; remediation firms say it kills none. Neither usually cites anything. For the agency split on bleach and its safety rules, see our does bleach kill mold page.

What the vinegar study measured

The paper most pages lean on is Rogawansamy and colleagues, IJERPH 2015, from the University of Adelaide. It is often described as a vinegar against bleach test. It is not: it tested 5 agents, namely Virkon, Cavicide, 70 percent ethanol, vinegar at 4.0 to 4.2 percent acetic acid, and tea tree oil. Bleach was discussed from other papers, not tested.

Each agent went onto a 9 mm paper disc on spore-seeded agar, read after seven days; a clear zone over 9.5 mm counted as activity. Agar is not drywall, and the authors say real surfaces still need testing.

Agent	Strength tested	Aspergillus fumigatus zone	Penicillium chrysogenum zone
Tea tree oil, liquid	100% oil	83 mm	43.5 mm
Tea tree oil, vapour	100% oil, no contact	81 mm	20.6 mm
Virkon	10% (ten times label rate)	19.25 mm	18.67 mm
Virkon	5%, 3% and 1%	No inhibition	No inhibition
Cavicide	undiluted	16 mm	16 mm
Cavicide	75%	No inhibition	No inhibition
Vinegar	4.0 to 4.2% acetic acid	No inhibition	15 mm
Ethanol	70%	No inhibition	No inhibition

Per Rogawansamy and colleagues, IJERPH 2015: ‘The use of vinegar as an antifungal agent may not be effective against the diverse fungal genera found in the indoor air environment.’ Vinegar did suppress spore production in the Penicillium it inhibited, and the authors suggested its lack of persistence may limit it to cleaning non-porous materials.

Six agents against mold, side by side

No study has tested every household option on the same material. This table puts the strength and the test surface next to each finding, so a lab plate is never mistaken for a wall.

Agent	Concentration tested	Test surface	What the source found	Source
Vinegar	4.0 to 4.2% acetic acid	Agar disc	Stopped Penicillium chrysogenum (15 mm zone), not Aspergillus fumigatus	Rogawansamy and colleagues, IJERPH 2015
Acetic acid vapour	1.9 or 2.5 microlitres per litre of air, 30 min	Inoculated fruit	Pome fruit decay from Penicillium expansum fell from 98% to 16%	Sholberg, Plant Dis 1998
Chlorine bleach	2.4% sodium hypochlorite	Lab carriers	Nonculturable after 5 min (non-porous) and 10 min (porous ceramic)	Reynolds and colleagues, J Occup Environ Hyg 2012
Bleach, hydrogen peroxide and three others	Peroxide at 17%; others not stated	Pine wood blocks	Growth stopped at first; spores recovered after rinsing	Chakravarty and Kovar 2013, via Rogawansamy and colleagues, IJERPH 2015
Hydrogen peroxide	0.2%	Agar plate, 5 min	0.44 log (63.30%) reduction of Aspergillus niger	Rabby and colleagues, Int J Microbiol 2025
Quaternary ammonium (Cavicide)	0.28% benzethonium chloride, 17.2% isopropyl alcohol	Agar disc	Undiluted: 16 mm zone on both molds; no effect at 75%	Rogawansamy and colleagues, IJERPH 2015
Quaternary ammonium	Not stated in abstract	Gypsum wallboard	Stachybotrys re-emerged within 5 weeks with the quat alone	Price and Ahearn, Curr Microbiol 1999
Borates (DOT)	0.25% and 2.00% g/v	Southern pine, up to 12 weeks	No mold protection alone; worked only with fatty acids	USDA Forest Products Laboratory FPL-RP-673
Detergent and water	Not a biocide	EPA guidance	Scrub growth off hard surfaces, then dry completely	EPA's Mold Cleanup in Your Home
10 commercial methods, incl. boron and ammonium products	Label instructions	Gypsum board and pine	None eliminated viable mold	Peitzsch and colleagues, J Environ Monit 2012

Agar and smooth carriers flatter every agent; wood and gypsum hold spores where liquid does not reach, hence the regrowth rows. The scales also differ, so ranking agents here would be false precision.

In Rabby and colleagues, Int J Microbiol 2025, that blend beat 0.2 percent hydrogen peroxide about 13 times over in log terms, but peracetic acid is a different chemical; it says nothing about vinegar alone.

How strong household vinegar is

The benchmark strength for white vinegar is 5 percent acetic acid: the USDA Complete Guide to Home Canning says ‘white distilled and cider vinegars of 5 percent acidity (50 grain) are recommended’ for pickling, and the FDA Compliance Policy Guide 525.825 says diluted vinegar should ‘in no case’ fall below 4 percent. The bottle states its strength.

Benchmark	Acetic acid	What it means	Source
FDA minimum for vinegar	4%	Diluted vinegar must state its strength	FDA Compliance Policy Guide 525.825
Vinegar in the Adelaide study	4.0 to 4.2%	The strength behind the one-mold result	Rogawansamy and colleagues, IJERPH 2015
USDA strength for pickling	5% (50 grain)	Recommended for white distilled and cider vinegar	USDA Complete Guide to Home Canning
EPA cap for vinegar as an inert	8%	Allowed in exempt minimum risk products only as an inert	40 CFR 152.25(f)

The tested vinegar sat at the FDA floor, about 1 percentage point under grocery strength: not a different product. A stronger cleaning vinegar that claims to kill mold should carry an EPA registration number.

Why vinegar has no EPA kill claim

Mold killers are pesticides in law. FIFRA, the Federal Insecticide, Fungicide, and Rodenticide Act, covers ‘any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest’, and EPA's What is a Pesticide? page says a product is likely one if its labeling ‘makes a claim to prevent, kill, destroy, mitigate, remove, repel’ a pest.

Per 40 CFR 152.15, ‘No person may distribute or sell any pesticide product that is not registered’, and a substance counts as one if the seller ‘claims, states, or implies’ it works as one. Grocery vinegar is sold as food and makes no such claim. That is why no regulator has checked a vinegar mold claim.

Question	Grocery vinegar	EPA-registered antimicrobial
Is it a pesticide in law?	Not as sold for food; only if the seller claims it controls a pest.	Yes, and it must be registered before sale.
Has EPA reviewed a mold claim?	No.	Yes, for the organisms and surfaces on its label.
Is there a contact time?	None from any regulator.	On the label, and the label binds the user.
Minimum risk exemption?	Only as an inert, up to 8% acetic acid, per EPA rule 40 CFR 152.25(f)	Not needed; it was reviewed
Registration number?	None.	EPA Reg. No. on the container.

The minimum risk exemption under FIFRA section 25(b) does not help. EPA’s list of active ingredients in 40 CFR 152.25(f) includes citric acid, clove oil and thyme oil, but not vinegar, which appears only among permitted inert ingredients as ‘Vinegar (maximum 8% acetic acid in solution)’.

Killing is not EPA’s goal

The question assumes killing is the job. EPA disagrees: EPA's Mold Remediation in Schools and Commercial Buildings says ‘it is necessary to clean up mold contamination, not just to kill the mold.’ Dead growth left on a surface is still growth on a surface.

Question	What EPA says	Source
Kill or remove?	‘It is not enough to simply kill the mold, it must also be removed.’	EPA's A Brief Guide to Mold, Moisture and Your Home
Hard surfaces	‘Scrub mold off hard surfaces with detergent and water, and dry completely.’	EPA's Mold Cleanup in Your Home
Porous materials	May have to be thrown away; mold may be ‘difficult or impossible to remove completely.’	EPA's Mold Cleanup in Your Home
Sterilising	‘In most cases, it is not possible or desirable to sterilize an area.’	EPA's Mold Remediation in Schools and Commercial Buildings
Recurrence	Without fixing the water problem, ‘most likely, the mold problem will come back.’	EPA's A Brief Guide to Mold, Moisture and Your Home

So vinegar’s weak kill record matters less than people think. It can help lift growth from a hard, acid-safe surface; it cannot make mold safe to leave in place. Our mildew remover guide sets out which chemistries lift mildew stains, surface by surface.

Where vinegar is reasonable, and where it is not

Find the material first. The surface decides whether growth can be reached and whether the acid damages what it touches.

Surface	Vinegar?	Why	Source
Glazed tile, glass, sealed hard plastic	Reasonable as a cleaner	Non-porous; growth scrubs off. Detergent and water is EPA’s method.	EPA's Mold Cleanup in Your Home
Cement grout	Not for routine use	Grout runs pH 11 to 13; acids weaken it and make it more porous.	Ceramic Tile Education Foundation, in Stone World
Marble, limestone, travertine, onyx	No	Calcite ‘dissolves readily in weak acid’.	USGS acid rain and stone page
Granite and natural stone tops	No	‘Do not use vinegar or lemon juice as cleaners.’	Stonemark natural stone care guide
Drywall, ceiling tile, carpet, insulation	No	Porous; may have to be discarded.	EPA's Mold Cleanup in Your Home
Bare wood framing	Unproven	No study read here tested vinegar on wood; treated pine regrew.	Peitzsch and colleagues, J Environ Monit 2012
Anything just cleaned with bleach	Not until rinsed	Vinegar plus chlorine bleach releases chlorine gas.	Poison Control

Material guides go deeper: mold in the shower for tile and grout, mold on walls for drywall, and mold on wood for framing.

A method that stays inside the evidence

This sequence uses vinegar only where nothing argues against it. Size limits and the full owner method are on our DIY mold remediation page; larger or hidden jobs follow the mold remediation process.

Step	Do this	Why, and the source
1	Measure. Over about 10 square feet, or sewage or other contaminated water: stop.	EPA DIY guideline.
2	Fix the moisture source.	EPA: otherwise mold returns.
3	Check the surface matrix. Porous or acid sensitive: no vinegar.	EPA; USGS; stone and grout makers.
4	Was bleach used on it? Rinse with water first.	Poison Control: never mix.
5	Wear gloves and unvented goggles.	EPA PPE guidance.
6	Scrub with detergent and water, or vinegar on acid-safe hard surfaces.	EPA hard surface method.
7	Rinse and dry completely.	Drying is part of EPA’s method.
8	Recheck days later: no growth, no musty odour.	EPA completion test.
9	Need a kill step? Use an EPA-registered product at its label rate.	The label is the law.

For contractors: vinegar on a scope or a protocol

Owners often try vinegar before calling. Record it and do not build on it: with no EPA registration, vinegar cannot honestly appear on a protocol or estimate as an antimicrobial step. EPA's Mold Remediation in Schools and Commercial Buildings also notes some states require registered pesticide applicators for biocides in schools.

Document this	Detail	Why an adjuster or auditor asks
Product in the protocol	Brand, EPA Reg. No., label use	Vinegar has no number to record.
Dilution and dwell time	From the label	No regulator states them for vinegar.
Surface list	Cleaned versus removed	EPA treats porous and hard materials differently.
Safety Data Sheets	Every chemical the crew handles	OSHA Hazard Communication, 29 CFR 1910.1200.
Owner’s prior treatments	What was sprayed, and when	Bleach residue plus an acid is a gas hazard.

Questions people actually ask

How long does it take for vinegar to kill mold?

No regulator publishes a time, because vinegar has no EPA-registered mold claim. The Adelaide study read its agar plates after seven days, which is not a contact time for a wall. Registered products state a dwell time on the label. Treat vinegar as a cleaner: scrub, rinse and dry.

What kills 100% of mold?

Nothing reliably does on building materials. In a 2012 Lund University study, none of ten commercial methods eliminated viable mold from gypsum board or pine. EPA says sterilising an area is usually neither possible nor desirable; remove the growth and fix the moisture instead.

Is bleach or vinegar better for mold?

In separate lab studies, 2.4 percent bleach made test molds nonculturable within minutes, while vinegar stopped one of two molds. Neither is EPA’s first choice: its hard surface method is detergent and water. Bleach has its own limits, covered on our does bleach kill mold page. Never combine them.

Can I spray vinegar on mold and leave it?

EPA says mold must be removed, not just killed, so leaving it in place is the wrong goal. The Adelaide authors also noted vinegar’s lack of persistence on surfaces. Spray, scrub the growth off, rinse and dry. Do not use it at all on marble, limestone or travertine.

Does vinegar kill black mold?

No study read for this page tested household vinegar against Stachybotrys, the mold usually meant by black mold. Colour does not change the method: EPA sizes the job by area and material, not species, and porous material with growth may have to go. Our guide to black mold versus regular mold covers identification.

Does vinegar kill mold on wood?

There is no direct evidence for household vinegar on wood. In studies on pine, agents that stopped growth at first allowed regrowth after rinsing, because spores sit below the surface. Dry the wood, clean it, and replace it if it has softened.

Can you mix vinegar and bleach to clean mold?

No. Poison Control says mixing vinegar with chlorine bleach releases chlorine gas that is very irritating to the airways, eyes, nose and throat. Use one product, rinse and ventilate before using another. The full mixing rules are on our does bleach kill mold page.