If you find paint that has gone bad, do not use it to paint your walls or drywall touchups. Instead, you should properly dispose of the paint at home.
Acrylic paint can smell bad when there is bacteria growth in the paint. Nothing to worry tho. You can still use the paint. smell will go away eventually. Usually cheap brand paints are easy to get contaminated. Windsor-Newton add antimicrobial component to their colors to prevent this.
One negative effect of using expired paint is that it may not adhere well to surfaces or may peel off easily. The color may also be inconsistent, and the paint may not dry properly. Additionally, expired paint may emit a foul odor, which can be unpleasant and potentially harmful.
General rule is recycle good usable paint if possible by donation to habitat for humanity or community projects. Reuse it on other projects around the home. Reduce by drying out either by air drying or mixing kitty litter in and dispose of the cans in normal garbage.
Open cans of paint don't last as long, but if the can is sealed after painting and stored in a cool, dry location, such as a heated garage or a basement, the paint can last for years. On average, paint lasts about ten years before it needs to be tossed, although some paint products may last up to fifteen years.
You might notice the consistency of your paint has changed. There may be a “skin” on the surface or lumps that won't stir out. If either of these is present, your paint has most likely expired.
I coated an entire smelly acrylic painting with bleach and let it sit. Now, the smell is gone! I've painted over it with new paint and all seems fine. This solution saved me for now, but my advice is to take a sniff test before you work with old paint.
This is a well-known issue across the paint industry, experts say. Graham Hill, managing director of ECHA Microbiology in Cardiff, said bacteria can grow in the paint can and release hydrogen sulphide gas, which causes a bad egg smell, and ammonia, which can explain the urine smell.
It's always a good idea to save some leftover paint, whether it's for touch-ups or a small paint project. But if you don't store it properly, years later—when hallway walls, exterior doors, or window casings need a little TLC—you might find that it has deteriorated beyond the point of being able to use it.
Typically, you might get 5-10 years from latex paints and 10+ for oil paints. Anything more than that and you'll likely need to buy new paint. If you need to dispose of old paint, contact your county for further details.
Recycling Your Paint
Sherwin-Williams is pleased to volunteer many of our stores as drop-off locations. Ready to drop off your leftover paint? Search for a Sherwin-Williams store* in any of the participating states/jurisdictions.
One of the best ways to tell if your stored paint has gone bad is to test it on a piece of board or timber. If lumping occurs it could be that chunky sized bits of paint have formed despite a vigorous stir. Extreme bad smell like rotten eggs might be highly concentrated.
Is it dangerous to use old paint? It can be dangerous to use old paint. Paints made prior to 1978 may contain lead and expired oil-based paints can emit harmful fumes that are toxic. Even latex paints made prior to 1990 may contain mercury which is dangerous to you and your family.
Paint fumes and odor can be harmful to certain people, like expectant mothers, children and babies, elderly, pets and those who have lung and medical problems.
When you store paint, it's important to recognize that mold development can be a real concern, especially if the paint is kept in less-than-ideal conditions. Paint cans that aren't sealed correctly or that sit in damp, humid spots can easily become magnets for unwanted mold growth.
Although opened paint can last up to around two years (if stored properly), you can usually tell if it has spoiled by looking at the expiration date. If however, it gives off a foul, rancid smell you should probably get rid of it (see further down to dispose of stale paint responsibly).
While you may not love the smell of fresh paint, spoiled paint has a scent that's much worse. "Paint that is beyond its shelf life can develop a rancid, sometimes rotten-egg odor," says Edrosa. If you open a can and find either of these problems, dispose of the paint and buy new.
Because the product is sealed within an oxygen-free environment, it enables the growth of anaerobic bacteria such as Sulfate-Reducing Bacteria. These microbes, which also cause microbiologically influenced corrosion, create hydrogen sulfide gas – otherwise known as rotten egg gas.
Paint stays good for a long time: oil-based paint for up to 15 years and latex paint for 10 years. Generally, paint that mixes smoothly when stirred can still be used. If latex paint has been frozen, brush it on a newspaper. If there are no lumps, it hasn't been damaged and can be used.
If your acrylic or house paint has dried up, don't worry – you can bring it back to life. Simply add a bit of water or a paint conditioner to the dried paint and stir it well. Start with a small amount, mix, and check the consistency. Repeat until it reaches the desired smoothness.
Step 2: Once Opened, Mix With a Stick
If there is no layer of thickened skin, gently stir the paint with a wooden stick until the product is uniform. If you notice lumps that do not dissolve, your paint is unfortunately not usable.
Texture: Bad paint tends to become lumpy, and when it's applied to a surface, it will be hard to get a smooth finish. It smells: When paint starts to go bad, bacteria grow, creating a sour smell.