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The Force of Doubt - is available now in Print and Ebook Version
The Force of Doubt

Disposing Paint Waste

Written by: Liz Flick-Belus and Maeve Milligan

Acrylic paints are a fantastic artistic medium, but they contain chemicals and micro-plastics. Once you finish your art, your brush water and leftover paints need to be properly disposed of. Sadly, it’s not as simple as throwing your wet leftovers in the nearest sink - you need to spend some time properly drying them first.


The binding agent in acrylic paint is essentially a type of plastic. So when you pour brush water and leftover paint down the drain you send pieces of plastic right into the ocean. Marine life consume micro-plastics from acrylic paints and other chemicals, such as quick-dry agents, pollute the water. While this is a problem around the world, it should be especially eye-opening for the citizens of Victoria, BC. The city, long heralded as a hotspot for environmentalism, is the last major coastal community to have untreated sewage flowing directly into the ocean. According to many sources the sewage outfall is “killing” the diverse life in Victoria’s oceans. A new sewage plant is on schedule to be completed late 2020, but the city expects sewage outfall to remain a problem for the next decade as they work through kinks. If you’re interested, there are links to learn more about this below. Needless to say, for Victoria citizens, proper disposal of brush water should be a high priority. 

That being said, acrylics are one of the more environmentally-friendly paints. Acrylic paints are water soluble and generally non-toxic. They’re safe for kids and animals and contain fewer dangerous chemicals than oil paints. Once dry, acrylic paint can be easily disposed of in the garbage. This will keep it out of the ocean where it does the most harm.

Don’t worry, this is an easy five-step process, and doesn’t it feel good to take the time to be environmentally responsible? 

A Five Step Guide to Environmentally Responsible Acrylic Paint Disposal

  1. Get your materials together. All you’ll need to dry your acrylic paint water is a wide container. The wider the better as a larger surface area will help speed up the drying process. It’s recommended to
    keep the distance from the bottom of the container to top of the water to under one inch if possible. It’s also best to use a container with a lid. For example, a wide tupperware like this would be a good choice for beginner painters. (But remember to use a container you won’t be eating out of again). For large amounts of watery waste, or if you plan on reusing your drying container, you’ll need something bigger. Alternatively, some artists may choose to skip the extra container and leave their brush water in the container used while painting.
  2. Pour your brush water and other waste into the new container or leave it in the brush water container and let it sit overnight. It’s best to keep a lid on your water to avoid spillage and keep curious children and pets out. A sip or two of acrylic paint water usually won’t harm your dog, cat, or baby, but large amounts can, so you may as well be better safe than sorry! The paint will settle at the bottom of the container and form a sludgy sediment. The water on top will be mostly clear and paint-free. 
  3. After the paint has settled, carefully pour out the clear water on top, making sure not to disturb the sediment. The acrylic sediment will now dry much more quickly. 
  4. Keep your container somewhere warm and/or well-ventilated for a few days until the paint has hardened
  5. Once your paint has hardened you can toss it straight into the garbage, or keep it for use in sculptures, mosaics, or other fun art projects. There’s no need to bring acrylic paint to hazardous waste centres or special disposals. 

The Cat Litter Method

Some artists use cat litter, old rags, or even commercial paint-drying products to absorb brush water and help it dry more quickly. These absorb both the water and paint so that it can be immediately tossed out without waiting for it to dry. While this may be better than pouring paint water directly down the drain, it still produces unnecessary, and potentially harmful, waste. Cat litter, for example, may contain deodorants, chemicals, silicone, plastics and other non-organic materials. Naturally, it’s best to avoid producing any extra waste in the painting process where possible. So, we recommend sticking with the traditional drying method, or looking into compostable alternatives for drying agents.    

Recycling and Other Tips for Leftover Paint

We’ve explained how to properly dispose of leftover paint water, but what about leftover paint? 

Well, our first bit of advice would be to buy only what you expect to use for a painting session. This might mean buying smaller containers or fewer colours. Remember that one of the best and worst things about acrylic paint is that it dries quickly. So once you’ve opened a container of acrylic paint it will only last so long, especially if you’re a beginner and not quite familiar with how to properly store paint. 

Our second tip is to store your leftover paint properly. Keep the lid firmly closed and store it somewhere relatively warm and dry. It’s recommended to keep your paint at temperatures between 18 and 23 C. If you’re from the west coast and that sounds crazy to you, don’t worry, just keep your paint dry and warm-ish. 

However, you might reach the end of your painting session and realize you won’t be painting again for a long time. It’s okay to admit it. If you have paint cans or bottles that you aren’t using anymore, you can recycle these at some depots. You don’t need to clean these whatsoever, just drop them off and the depot will take care of the rest. If you’re in B.C., you can use this link to find out where you can recycle these containers. If you’re not in B.C., then look up “(the name of your city) recycle paint”. These paints are recycled and reprocessed into more paints, so why waste someone else’s good paint?


Links to Information about Victoria Sewage