Are Oil Paints Toxic? Yep.

The great debate, are oil paints toxic, and can painting with oil paint be bad for your health? I have read a lot on both sides of the argument and frankly people who don't think oil paints are toxic, don't understand basic organic chemistry (which isn't surprising, it is a hard topic). Happily I do, and yes oil paints are toxic, but not so much that it should ever cause a problem as long as you know the dangers, because knowing is half the battle. Let's talk about it...

A quick Warning from Winsor and Newton: 

Winsor & Newton Artists' Materials do not present any major hazard when used with care and common sense. It should, however, be emphasized that as with other chemical products, high standards of general hygiene should be adhered to, both during and after use of these products and warnings given on individual products should be followed. Prolonged contact with the skin and ingestion (or swallowing) of the product should be avoided.  This includes avoiding practices such as applying colour with the fingers or pointing brushes in the mouth. 

1. Oil paints dry by Oxidation and not by Dehydration:

The reason oil paints take so long to dry is because they dry by a process called oxidation, where as watercolor and acrylics dry by dehydration.

If you would like to read more about this process, you can read here, or here.  Simply, the process consists of oxygen entering the paint film and creating a chemical reaction. This releases heat, free radicals, and some carcinogens such as VOC benzene.

Oil paints do not release such a large amount of VOC benzene that there is a huge cause for alarm, however, it is important to be aware of the process and that ventilation is important.

How to fix it:

Avoid sleeping in your painting space, do not allow oil paints to remain on your skin for long periods of time, and do not eat, drink, or smoke in your painting area. Use house plants that specifically remove VOC benzenes such as peace lilies.  

2. Toxic oil paint pigments, specifically Cadmium and Cobalt:

I once read someone talking about how oil painting pigments are naturally occurring earth minerals, and therefore are not toxic at all. Well, uranium and argon gas are also naturally occurring...so there is that. The pigments below are considered carcinogenic:

Highly Toxic Pigments/ Known or Probable Carcinogens:

Burnt and raw umber; cadmium red, orange, and yellow; chrome green, orange, and yellow; cobalt violet and yellow; lead or flake white; naples yellow.

Moderately/ Slightly Toxic Pigments: 

Alizarin Crimson; cerulean blue; cobalt blue and green; chromium oxide green; prussian blue; zinc white.

These pigments cause the most harm in their powdered form, where they can be inhaled. However, the oil in the paint allows for the pigments to also be absorbed through the skin. Personally I have always wondered if the reason several of the great impressionists suffered from intense arthritis is due to poor paint hygiene practices. This is an image of Renoir with his crazy arthritic hands.

Cadmium and cobalt are the primary pigments you need to look out for; however your skin only absorbs a small amount of cadmium and cobalt at any given time. Be aware that cadmium is an accumulative metal and will slowly build up in your system. When absorbed it takes the place of zinc in the hemoglobin and can cause some eventual damage.

How to Fix it: 

Winsor and Newton give the following advice when it comes to Cadmium and Cobalt:

Wash at the end of each work shift and before eating, smoking and using the toilet. Promptly remove any clothing that becomes contaminated. Use appropriate skin cream to prevent drying skin. When using do not eat, drink or smoke. 

Make sure that you always wash your hands, do not put your paint brushes in your mouth, and if you want be extra careful you can always wear disposable, plastic gloves while painting. Which a lot of artists do, by the way.

3. Watch out! Oil paints can spontaneously combust! 

Technically this is true. Oil and solvents left on a paper towel or rag will still continue to oxidize, which creates heat, which can cause said paper towel or rag to combust! I have never seen this happen, I have never heard of it actually happening, but technically it could happen.

How to Fix it: 

Put your rags in a metal canister that is filled with water. Which I have also never seen anyone do. However, you should probably not smoke (unless you are Pollack or someone of the sort) or light things in your painting area just in case.

4. Solvents:

Even with odorless solvents you can tell there is something in the air.

How to Fix it: 

Read here.

5. How to Protect Yourself: It's Easy! 

Be smart, wash your hands, make sure you have good area ventilation, do not put things in your mouth, when sanding use googles and face masks, be careful when spraying solvent onto paints and use protective gear, and buy some house plants.

For more about painting check out my main Tips and Techniques page.