“Arboreal Serenity”, oil on canvas, 16X20, 2017
Guide to Non-Toxic Oil Painting
An oil painters' experience with safer
oil painting materials and essential oils
by Mike Bergen
It is still commonly believed that oil painting is dangerous and toxic; that it is environmentally hazardous and a danger to your health. This was true at one time, however modern materials and method have mitigated many of these hazards and today oil painting can be one of the safest painting mediums, if used correctly.
1. Paint - There is nothing inherently toxic about oil paints. The paint is simply pigment suspended in a binder such as linseed oil, safflower oil, poppyseed oil or walnut oil. Each of these oils is plant-based and non-toxic.
Some pigments however, such as Cadmium, Cobalt, Mercurial Sulfides and Lead can be very hazardous. In the past these pigments were ground up into a very fine powder which could be absorbed by the skin leading to serious medical issues. Most modern methods grind up the pigments to a more course powder which cannot be so easily absorbed into the body. Most modern oil paint tubes thus no longer carry the federal government safety warning labels, except ones that contain toxic pigments such as cadmium or lead.
Instead most have a label which certifies that they conform to ASTM D-4236 and ASTM- D-4302 and that they have been properly labeled for chronic health hazards. ('Since knowledge about chronic health hazards is incomplete and warnings cannot cover all uses of any product, it is not possible for precautionary labeling to ensure completely safe use of an art product ASTM ').
If there are any hazards associated with the material they should be stated on the tube. For example Cadmium should not be spray-applied, due to severe inhalation hazard. So it is still wise to either use barrier cream or gloves when painting with oils. Paints still contain pigment particles some of which may have minor adverse physical effects if ingested or regularly applied to soft skin, however they are now thought to be much safer.
2. Mediums - A normal part of the painting process is using a medium to alter the painting characteristics or appearance.
Lavender oil was the medium of choice from the fourteenth century until the Industrial Revolution when turpentine replaced it because it was cheaper. Thus the smell associated with oil painting was turpentine. Turpentine is however very toxic and is now rarely used. Instead people most often use Oderless Mineral Spirits (OMS). OMS thinners don’t smell as much, but they are still toxic.
Even Gamsol which is advertised as more refined, is still toxic. One way to avoid mediums is to paint right out of the tube with a palette knife. Since this is not always possible or desirable, a better option is to use safer oils such as lavender oil, walnut oil or linseed oil.
Each of these oils has its own advantages and disadvantages: Lavender oil has a strong odor that some consider pleasant. It has the consistency of water and is a strong and very effective solvent, but expensive. There are also some health considerations due to unique VOCs, and use of ventilation is recommended.
Walnut oil is thicker and very slippery and I find it difficult to paint with but great for cleaning brushes.
Linseed oil is the most common binder in oil paints but it may turn yellow in time.
Another alternative is to use a solvent-free non toxic gel mediums such as Gamblin’s Solvent-Free (non toxic) Gel Medium. Alkyds in oils cause paintings to dry faster and usually you can paint over them the next day. I find a small amount of alkyd walnut oil to be a useful medium. Gamblin’s Solvent- Free Gel Medium has alkyd in it.
Rembrandt, The Artist in his studio, 1626, oil on board, (Wiki Art)
3. Brush Cleaning - Most painters use an OMS for brush cleaning (OMS stands for 'odorless mineral spirits', which is a petro-chemical solvent derived from NAPHTA). This is likely to be fine outdoors or in a very well ventilated room. However a better solution is to use a non-toxic solvent such as the Bio-based Artists Solvent sold be The ART Treehouse or Turpenoid Natural which is also considered non-toxic. Alternatively many of the essential oils also make good brush cleaning solvents. Lavender oil is actually a stronger solvent than turpentine. Walnut oil is good for cleaning brushes while painting. Final cleaning however
should be done with soap and water.
4. My present process:
- paint with any brand of artist grade paints, my preference
is Gamblin or M. Graham
- during painting I clean brushes in walnut oil and clean rags
or paper towels
- for a medium I use Gamblin Solvent-Free Gel Medium if I
want an impasto effect, or Lavender oil for thinner paint
- as a turpentine substitute for palette cleaning I use either
lavender oil or The Art Treehouse Artists Solvent
- at the end of the day I clean my brushes in Turpenoid Natural followed by water and Masters Brush/Hand Cleaning Soap
- I store any remaining paint on the palette in a closed container also containing a small amount of clove oil to slow the drying process. Ideally this should be kept in a freezer or refrigerator
M.Graham (paint) www.mgraham.com
Gamblin (paint) www.gamblincolors.com
The Art Treehouse (various non-toxic mediums)
Oil paint can be placed on top of acrylic paint
(but not the other way around).
Thus one can do an underpainting in
acrylic which is water based, largely non-toxic and fast drying
Oil painting is great for texture and for adding subsequent
soft edges (because it is slow drying).
Oil painting also makes a great finished surface for a painting and
eliminates the need for glass or plexiglass framing.
This is a link to a good article on choosing a brand of oil
Mike Bergen's Art Homepage