Health and Safety Practices: Toxicity and Oil Painting
The following are tips on working with the various materials used in oil painting to minimize toxicity. Before you begin a painting, it’s a good idea to better understanding the products you’ve invested in. Therefor, when purchasing any support, paint, or medium, make sure the source discloses their process and constituent parts. While all products must conform to governmental standards some brands have higher manufacturing standards based on their company philosophy which can lead to varying levels of chemicals present in their products, such as unnecessary fillers in oil paints.
Most paints are comprised of just pigment and oil (paint fillers vary with brand, when purchasing oil paint look for brands that disclose and identify their fillers), with many pigments derived from non-toxic sources. Some pigments are hazardous, such as lead, cadmium, mercurial sulfides, and cobalt based pigments. These hazardous pigments historically were quite toxic due to the practices of the time but our modern pigments are manufactured to governmental health standards. A good practice which many painters employ is to wear gloves or barrier creams when working with oil paint.
Altering the consistency of oil paints through introducing mediums is a normal part of the painting process. There are many options available in the modern art stores of today. Working with single oil mediums such as linseed or walnut are very safe as are gel mediums that do not contain solvents. Alkyd mediums, which are polyester resins, are petroleum based products and sometimes have solvents incorporated in them, help speed up the drying time of oil paint. Mediums which incorporate varnish are to be avoided for they weaken the polymerization of oil paint layers and lead to cracking.
Solvents are used for both mediums and cleanup in the painting studio. Historically spike oil, or lavender oil, was used as a solvent before being replaced with a cheaper alternative, turpentine. Today, there are odourless mineral spirits (OMS) that, while still very toxic, have reduced the unpleasantly strong odour of the original product. Spike oil is the best solvent for incorporating into mediums while OMS is best reserved for cleaning brushes, etc. While using solvents in the studio it is best to reduce their evaporation into the environment through careful management of their containers, keeping lids closed while not using the solvent is a prime consideration. Invest in brush cleaners and medium dippers that have lids. There are also many products available that can help reduce exposure to the harmful effects of solvents, such as inexpensive dispensing bottles which control the contact of the solvent with air.
4. Brush cleaners
Remove as much oil paint as possible prior to cleaning the brushes with soap. After wiping all excess oil off brushes cleaning them with solvent or alternatives such as turpenoid natural work best for this. Brush cleaning canisters with snap on lids work well for keeping solvent for this purpose. The best soaps for brush cleaning are those without harsh detergents.
Most varnishes contain solvents and the same safety guidelines should apply when using to minimize inhalation and exposure to product.
6. Waste Disposal
Used paint solvents can be reused by pouring the clear liquid into the original container and allowing the residue to dry prior to disposal. Never pour oil paint or solvents onto the ground or into a drain.
palette - scrape oils onto paper towel or scrap paper and dispose in a plastic bag capable of being sealed
oily rags - all rags used for wiping paint, oils, solvents, etc. should be disposed of in a plastic bag capable of being sealed
Extra plastic shopping bags are great to have for the purpose of waste disposal, they can be tied off to seal the waste from air. As oil drys it can produce heat, in combination with combustible materials such as paper towels and contact to air this can cause spontaneous combustion. Maintaining appropriate waste disposal in the painters studio is key.
General Safety tips in the Studio
• Avoid eating, drinking, and smoking while in the studio • Avoid excessive contact of hazardous oil paint and solvents with skin • Do not allow solvents to evaporate and use the least amount necessary • Always have good ventilation when working with solvents • Clean up spills immediately • Wear a respirator when working with dry pigments
Used by permission from Whitney McCrary, SAGA member.