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How to Safely Dispose of Acrylic Paint



Acrylic paints are water-based, making them much easier to dispose of than other types of paint. They don’t emit any toxic fumes, and any messes can be easily cleaned with soap and water. With that being the case, you’d expect it to be very easy to dispose of acrylic paint. However, you can’t throw away a can of wet paint and you can’t pour it down the drain. So, what are you supposed to do?

Luckily, disposing of acrylic paint is actually a pretty simple process, and we’re going to lay out the steps for you in this article. There are just a few important points you need to be aware of, so we can do this in a manner that’s safe for the environment, yourself, and the plumbing as well.

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The Basic Rules

In general, you want to dispose of acrylic paint as a solid, rather than a liquid. This is going to be your main rule regarding the disposal of acrylic paint. Even if you’re only getting rid of a small amount, such as the leftover in a small tube, it’s not a good practice to throw it away with wet paint still inside.

The goal is always to allow the paint to harden first. Luckily, that’s pretty easy to do with a small amount of paint, such as the leftover in a small paint tube. However, it can be a bit more difficult with larger volumes of leftover paint. Don’t worry though; we’re going to go over the steps you need to easily dispose of small and large amounts of paint alike.

Don’t Pour it Down the Drain

Even though acrylic based paints are water-based, they should never be poured down the drain. The pigments used in professional-grade acrylic paints are toxic. They can cause problems for waste-water treatment plants, and eventually, even the environment.

But it’s not just professional-grade acrylic paints that can pose a problem. Though student grade acrylic paints are marketed as non-toxic, they’re still problematic for plants treating wastewater. So, no matter what type of acrylic paint you’re using, don’t pour it down the drain.

paint roller
Image Credit: IgorShubin, Pixabay

Dealing with Your Rinse Water

So, what should you do with all your rinse water at the end of a painting session? There’s no way around having dirty rinse water after painting. But again, it should never be disposed of by pouring it down the sink. Even though it may seem harmless, rinse water still contains enough paint to cause problems for wastewater treatment plants, or to cause potential harm to the environment.

First, you can minimize the mess in your wastewater by wiping off excess paint before rinsing your brush. You can use an old rag or even an old canvas. Just make sure to allow the paint on the rag to harden before you throw it away. By pre-wiping your brushes before rinsing them, your rinse water will go a lot further between changes, reducing the total volume of rinse water you have to dispose of.

Still, there’s going to be some rinse water at the end of your session, no matter what you do to minimize it, and that’s ok. The best way to safely get rid of it is to allow it to evaporate. To do this, you’ll need a five-gallon bucket to pour the rinse water into, and a screen lid to prevent any kids or critters from getting into your rinse water.

Simply pour all of your rinse water into the bucket whenever you’re done. Then, leave the bucket outside in the sun. All of the water will evaporate in a few days, leaving just the hardened paint behind. Once it’s hard, you can just remove it from the bucket and throw it in the trash.

Consider Donating Your Unused Paint

If you’re only trying to dispose of small volumes of unused paint, then your best bet is to let it dry out before throwing it away. On the other hand, if you have large buckets of paint that’s still good and you need to dispose of it, trashing it isn’t necessarily the best option.

In such cases, it might be beneficial to look for a local charity or organization that could use that paint. Not only will this help out that organization, but you’ll no longer have to deal with the disposal process, making it a win-win for everyone involved.

If you’re going to donate your paint, you need to ensure it’s properly stored so it stays good. This means keeping the lid fully closed with the can or bucket stored in a cool, dry place. And in general, you’ll only want to donate cans that are about half full or more.

Some places that will often take leftover paint include school clubs, community theaters, non-profit organizations, charities, and more. You could even try putting up a classified ad on a site such as Craigslist to see if anyone local is in need of paint. They’ll probably even come pick it up from you.

Image Credit: Sven Brandsma, unsplash

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Disposing of Acrylic Paint

Regardless of how much acrylic paint you have to dispose of, the following steps are the proper procedure. Follow them in order, and you’ll have no issues trashing your old paint. Just remember to try and donate it first if you have a good amount of paint left over. It might turn out to be easier than disposing of it yourself.

Step 1: Check Your Local Regulations

While these steps are a great general guideline, different states and jurisdictions have their own specific rules regarding the disposal of acrylic paints. It’s a good idea to check your local regulations first, to ensure that you’re doing everything in the legal way that’s permitted in your area. Once you’re certain that you’re following all local regulations, you can move on to step 2.

Step 2: Check for a Drop-Off Site

If you live in certain states, there’s a special service that you can make use of. It’s only available in 10 states at the moment, but it can save you a lot of hassle if you’re in one of those states. The service is called PaintCare, and you can find their many drop-off locations through their website. When you drop off paint to PaintCare, you won’t have to dry it out first, saving you the time of going through the next six steps.

Of course, if you don’t live in one of the few states offering drop-off sites, then this won’t be available to you. If you’re not in one of those states, you can skip this step and move on to step 3.

Step 3: Don’t Throw the Paint Out

Your first natural thought is likely to just throw away the paint. But this isn’t the right approach. We need to let the paint harden before trashing it. So, gather up all of your old paint containers with leftover paint and bring them outside.

Step 4: Leave the Paint Outside

To dry out all of that leftover paint, we’re just going to open the lids and leave them outside. The sun and air will dry out the paint. It could take several days for the paint to harden up completely, depending on how much paint you’re drying and what the weather is like where you live.

paint roller
Image Credit: IgorShubin, Pixabay

There are a few things to keep in mind here. First, you don’t want anything to get into your paint. Animals might try to eat it and kids can get into it and make a mess. So, try to put it somewhere that nothing can reach it easily. Also, keeping it covered with a mesh lid of some type can help to keep critters out.

If you’re just drying out leftovers in paint tubes, then you won’t have long to wait. Just take the caps off the tubes and leave them anywhere with fresh air. Paint cans can be left open with a mesh covering, and they’ll dry faster with more exposure to air and sun. So, be sure to find a safe but exposed place for paint cans. Watch out for rain though. If the rain comes through and soaks your paint, you might have a long wait ahead of you!

Step 5: Add a Hardener

If you’re only drying out leftover paint in small tubes, it’s not going to take long and you won’t need extra help. Paint cans are a different story though. If you have a significant amount of leftover paint in a can, it could take quite a long time to dry out and harden up. In such cases, you’ll want to speed the process along with the help of a hardener.

You can purchase a paint hardener from your local home improvement store. Alternatively, you can find one available online with a quick search. But there’s a cheaper and easier option that works just as effectively; cat litter. You can find cat litter at any local store and it’s very affordable. Just pour the cat litter or your chosen hardener into your paint and continue to let it sit in the fresh air and sunlight. It should harden up very quickly once you add kitty litter or paint hardener.

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Step 6: Wait Until it’s Hard

At this point, all you can do is wait. You’ve already set everything up, now the paint must harden. Depending on how much paint you’re drying, the weather, and whether or not you used a hardener, this process could take a few hours or a few days. Either way, you must wait for the paint to be completely hard.

Step 7: Throw Away the Hard Paint

Once the paint is fully hardened, you can remove it from the can or bucket. If you’re drying paint tubes, you won’t need to remove the paint. Just throw the paint away. But for paint in a can or bucket, just remove the hard disc of paint. Once removed, you can simply throw it away in the trash can. It’s now harmless.

Step 8: Recycle the Can

The final step in the process is to properly dispose of the can or bucket by recycling it. Ensure there’s no paint left in the container and either place it in your recycling bin for pickup or take it down to the recycling plant for drop off.

Image Credit: bidvine, Pixabay

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While you don’t want to just throw away containers of wet paint or pour them down the drain, it’s still not difficult to dispose of them the correct way. Just follow the simple steps we’ve laid out here, and you’ll be able to safely throw out your old acrylic paint.

Remember, if you have large amounts of paint to dispose of, you might try donating them first. There are many groups that could likely benefit from that paint, even if you can’t find a use for it anymore.

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Featured Image Credit: zivica, Pixabay


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