When the workday ends and the paint is still wet on your brushes, it can be tempting to simply rinse them in the nearest sink. Many painters, both professionals and DIY enthusiasts, have done this for decades. But is it safe to wash paint brushes in the sink? The short and scientifically grounded answer is a firm no, it is not safe for wastewater systems and especially not for the environment.
The Science Behind Paint Residues in Wastewater
Studies commissioned by the Swedish Environmental Protection Agency (Naturvårdsverket) and Svenskt Vatten (2016) have shown that paint residues are a significant source of secondary microplastic pollution. Every time a brush is washed in a sink, small plastic and pigment particles are released into wastewater streams.
While wastewater treatment plants in Europe are efficient, they can only remove 80–95% of microplastics. That means the remainder passes through filtration systems and ends up in rivers, lakes, and oceans. Even small local discharges can accumulate, causing measurable environmental damage.
Why Paint Produces Microplastics
-
Many paints contain synthetic binders such as acrylics, vinyl, and other polymers. These break down into microplastic particles when washed.
-
Pigments and additives are often combined with these polymers, making the particles even more persistent in the environment.
-
Once released, microplastics do not biodegrade. They can remain in aquatic ecosystems for hundreds of years, entering the food chain.
The Plumbing Problem
Aside from environmental damage, washing paint brushes in sinks can also harm your own plumbing. Paint residues harden over time, leading to clogged pipes and costly repairs. Municipalities across Europe frequently warn both homeowners and businesses that paint disposal via household drains is illegal or strongly discouraged under local wastewater regulations.
The Environmental Impact
Microplastics are now recognized as one of the fastest-growing forms of pollution. According to the European Chemicals Agency (ECHA), paint is among the top contributors of microplastics released into the environment each year. Once in waterways, these particles:
-
Accumulate in sediments and soils.
-
Are ingested by fish, birds, and other wildlife.
-
Carry harmful chemicals that can leach into ecosystems.
-
Ultimately make their way back into the human food chain.
In other words, the simple act of rinsing a brush in the sink can have long-lasting, invisible consequences for the environment and human health.
A Better Alternative: Lavabrush
This is exactly why we developed Lavabrush—a patented cleaning system designed for professional painters. Lavabrush allows you to:
-
Clean up to 15 brushes with only 1.5 liters of water.
-
Capture and separate paint residues and microplastics before they enter wastewater systems.
-
Save time and resources, keeping brushes in top condition and ready for the next job.
By adopting better practices, painters can continue their craft without adding to one of the most pressing environmental issues of our time.
To answer the original question:
No, it is not safe to wash paint brushes in the sink. The science is clear, doing so contributes directly to microplastic pollution and undermines sustainability efforts in our industry.
Instead, painters have a responsibility to adopt safe, environmentally sound cleaning methods. With tools like Lavabrush, there is no longer a reason to let microplastics flow into our waterways.
Paint responsibly. Protect your craft. Protect the planet.