Extreme care is required when handling pigments whether in paint tubes or in dry powder form. Pigments can enter through the skin, mouth, and nose—causing serious injuries and sometimes irreparable damage. The toxicity or hazard level of pigments varies according to how it gets into the body. A pigment that is considered non-toxic when coming into contact with the skin may turn highly toxic when ingested or inhaled.
An artist should check the label and do further research to determine the toxicity or potential health hazards of the pigments in their colour palette. A pigment considered extremely/highly toxic will cause serious injuries when a small amount gets into the body through absorption, ingestion, or inhalation. A pigment considered moderately toxic will cause minor injuries - whether permanent or temporary - when it gets into the body. A pigment considered slightly toxic will result in temporary minor injuries. A non-toxic pigment means no detectable injury will result when small quantities get into the body; however, it does not mean safe or non-hazardous. An accumulation of non-toxic pigment in the body over time can still result in some injuries. Age and physical conditions will determine how effectively the body can counter the accumulation.
Pigments containing heavy metals such as antimony, barium, cadmium, chromium, cobalt, copper, lead, manganese, strontium, and zinc are highly toxic. Pigments that do not contain heavy metal pigments are considered non-toxic but must still be treated with caution. Paints described as 'hue', such as "cadmium red hue", indicate that there is no (or negligible amount of) toxic metal contained in the product.
The following pigments contain some level of toxicity and should be handled carefully.
Alizarin Crimson, Anthraquinone, Antimony Black, Antimony White, Barium Yellow, Burnt Umber, Cadmium Barium Yellow, Cadmium Red, Cadmium Orange, Cadmium Vermilion Red, Cadmium Yellow, Carbon Black, Cerulean Blue, Chrome Green, Chrome Orange, Chrome Yellow, Chromium Oxide Green, Cobalt Blue, Cobalt Green, Cobalt Violet, Cobalt Yellow, Emerald Green, Flake White, Lithol Red, Lead White, Manganese Blue, Manganese Violet, Molybdate Orange, Naples Yellow, Prussian Blue, Raw Umber, Paris Green, Smalt, Strontium Yellow, Toluidine Red, Vermilion, Viridian, Zinc White, Zinc Yellow.
The use of turpentine in the studio increases the risks of absorption through the skin because they act as a vehicle to carry the pigment into the body which would not otherwise pass. It is a little-known fact that in the nineteenth century, turpentine was used as a liniment to carry herbs into the body through the skin.
Artists who feel they are only being exposed to small quantities of pigments may adopt a lackadaisical attitude towards the risks of pigment poisoning. That is imprudent because injuries can still occur from repeated absorption, albeit in small quantities. A prudent artist will treat all pigments as hazardous or potentially hazardous and take the necessary precautions.