Mineral Spirits

[Tom Edgerton]

Be careful, though, in this discussion. Inhalants are not the only problem. Turpentine is more toxic and is absorbed through the skin, and mineral spirits are much less of a problem in this regard.

The best discussion of the various solvents is, I think, at the Gamblin site.

--Tom

[Richard Bingham]

Originally Posted by Tom Edgerton

Be careful, though . . .

Absolutely. Painting at the easel, a competent adult will "be careful" enough by dint of reasonable workmanship. Poor ventilation is less obvious, and more insidious. However, it's no more adviseable to drench painting surfaces, tools, brushes and hands with MS than with turps.

Gouache is a better material choice for those terrorized by possibilities of toxicity.

Tom, could you be so kind as to point us to a qualified source of factual information on the toxicity of turpentine? The Gamblin site appears to be a "sales pitch" in the main, and states nothing more substantive than turpentine is "a known respiratory irritant". It goes on to speculate on the misuse of turps by "painters of 50 years ago . . . [who] created huge canvases of oil colors diluted with turpentine".

Further, "Rembrandt used no painting mediums." A statement knowledgeable painters should find at least controversial if not ridiculous. The intent is to convince readers of the adviseability of using Gamblin's proprietary mediums.

Gamblin's market strategy has been to emphasize that their products are non-toxic and ecologically friendly. Certainly laudable aims in themselves, no doubt reflecting a realistic assessment of the sensibilities and anxieties of their customer base. However, they seem insecure enough with that stance that information on the site for the most part evades hard facts, and tends toward hyperbole and unsubstantiated opinions.

[Sharon Knettell]

I had an hour and a half conversation with Micheal Harding ( the paint maker) about this and other subjects, (his nickel, thank heavens).

He recommends using ONLY the purest turpentine. He only uses mineral spirits to clean his paint making machines as it is a powerful solvent and breaks down paint very efficiently. This is not the sort of thing you want in your paint . He had a more detailed description of how mineral spirits can weaken your paint surface but I cannot at this time find my notes. He DOES not sell turpentine as far as I know.

I use mineral spirits only for brush cleaning now.

[Tom Edgerton]

I have info somewhere on the toxicity of turps, but I can't lay hands on it. I'll post it when I can find it.

For me, it's an academic discussion anyway. I have to use mineral spirit exclusively in the studio as I'm allergic to pine trees and pine products.

[Richard Bingham]

Part of the problem of determining the safety of thesesolvents for our purposes, is in defining the products. "Pure spirits of gum turpentine" is supposed to be definitive, but lately is applied to the "stumps and limbs" brew that reeks of creosote. It is NOT the same as the turps distilled only from the gum exudations of suitable pine species. Some grades are refined to the extreme and are used in . . . cosmetics! (as are highly refined petroleum distillates as well)

Information on the toxicity of turps and MS is "generically" available if you access the OSHA pages on each, but include a wide range of materials and grades which are not applicable to studio painting. Specific materials are not clearly identified. I really don't know what benefit information from that quarter is to us, since exposure levels stated are ridiculously high, and the bottom line is, if you drink or bathe in either one for a long enough time, you're gonna die .

Mineral spirits is a catch-all term, many grades of MS derive from that fraction of petroleum distillation that entails everything from #2 diesel fuel and kerosene through highly refined grades with specific uses. The most refined being white spirit and the "press wash solvent" printers use to clean their presses. The range includes solvents which are more or less flammable, such as solvents used to clean mechanical parts in repair shops.

K-1 kerosene is probably the best solvent for cleaning oil paint from brushes and tools because it is the most penetrating solvent in that "genus". It is not particularly odorous. It would also be the worst possible additive in oil paint!

Mr. Harding's comments reiterate what I was taught a long many years ago, i.e. the "cutting" or solvent action of petroleum distillates is deleterious to the strength of paint films bound by natural oils and resins in ways turpentine is not.

Certainly Tom has very good reason to avoid turpentine, but this discussion is more than academic, as he can adjust his painting materials and methods to accommodate the omission of turpentine, and the discussion of the merits and disadvantages of materials should be useful for arriving at the best alternatives.

It's possible mediums and varnishes containing turpentine may not distress individuals with a turpentine sensitivity, even when the "straight stuff" does, since resins and oils dissolved in turps change its vapor pressure and volatility.

In all cases, whether one has materials sensitivities or not, avoiding contact with the skin, and ample ventilation in the studio are inviolate rules for the use of all materials associated with oil painting.

[Tom Edgerton]

Richard--

Let me clarify....the discussion of mineral spirits vs. turps is academic for me, as I can't use turps anyway. This is not to imply it's academic or irrelevant for anyone else. Quite the contrary--studio safety is vital.

Best-T

[Richard Bingham]

Tom, thanks for that. This subject strikes a chord with me, because I am interested in the mechanics of craft, and also because I'm one of those "nut-cases" who revels in the aroma of the studio and painting materials in general - the acetic-acrid smell of flake white, linseed oil, the various resins, turps, spike . . . all of it!

By the same token, I'm aware of the hazards of inadequate ventilation and careless exposure, and take every precaution against them. I know first-hand how serious problems allergic reactions and sensitivities pose to those affected.

A serious painter from his 'teens, in his 60's my father precipitately developed a sensitivity to turps which caused painful lesions to erupt on his hands upon contact. As his preferences for painting materials and methods were well established at that point in his life, it caused a lot of stress and inconvenience in his work, to say nothing of the physical discomfort and questions of health. Without rhyme or reason, after nearly a year the reaction to turps ceased abruptly as the onset had been, and he was able once again to work around it with no problems.