Flake White, Cremnitz, Underpainting White

Ceiling fan, open windows: drying out the toxic off-gassing.

A late post, with an update on the nasty oil painting incident of last week, an incident which is still giving my body some fits.

It all started last Monday, when I was reworking the big desert canvases, painting the stretched sides and tweaking within the body of the image. I had a big tube of flake white, unopened, and since I was running out of titanium and was working on some of the coolest area of color, I thought I might as well use the flake white.

Flake white, as it turns out, is the industry’s name for a combination of lead and zinc white oil paint for artists. Lead white, which was very popular in house paints, is now banned in the US and has to be cleaned up as a hazardous material if it’s found on housing stock. But its toxicity was confined, I thought, to lead dust (as generated, for example, by sanding) and lead flakes — particles, in other words, not gases. Moreover, last Monday I didn’t even realize that flake white was a lead paint, just that it was a cooler,white than titanium and more opaque than zinc.

I was using an alkyd medium, Winsor-Newton’s Liquin, with the flake white, in part because of the thick consistency of the paint. I did not become consciously aware of the change in air quality until Wednesday, although I did find myself changing shirts more often because they “smelt funny.” On Wednesday I walked into the studio and thought, “oooo, ugh, I need to air this place out.”  The studio was rebuilt from the studs out and is very energy efficient, i.e. very air-tight.

Thursday, I fanned the door vigorously a number of times, but the smell seemed to be getting worse. Then I turned on the ceiling fan and opened one window a crack. By Thursday afternoon, I decided that I needed to open a high window or two and use the ceiling fan on reverse to rid the place of fumes. By Thursday night, I had a face rash, a cough and even with a three-hour afternoon nap, felt generally wretched. And it dawned on me that the studio may have been the source of this reaction.

When I thought of the odor, I realized I had had the same odor occur at least once, perhaps twice, before, with an oil paint called “underpainting white.” I don’t remember the brand but I was using it as a quick drying under-cover white, over an couple of masonite boards that I was recycling. That was a summer experience, so I opened all the windows, set the paintings outside to dry, and thought I  may have just used the paint too thickly or too much all at once.

But lead white dries faster than any of the other whites, and my suspicion is that that particular “underpainting” white used lead white as its base (other “underpainting whites use alkyd bases and titanium white, which should be perfectly non-toxic). Another term for all-lead (no zinc) white oil painting for artists is Cremnitz. No artist’s paints made in the US use lead at all, but of course, many oil paints are manufactured outside the US and are readily available within the country.

Besides the lead paint, the other factor that may be contributing to the toxicity is that I am using an alkyd medium rather than linseed oil as my painting medium. My suspicion is that it’s the combination of the alkyd medium (sold under various names, Galkyd and Liquin coming most readily to mind)  and the lead white that caused the toxic off-gassing. I have found nothing in the literature to confirm this but anecdotally, at least, I believe that’s the case. Alkyds combine a polyester and a linseed-like medium for faster drying. My chemistry is insufficient to make any data-based comments, but my experience tells me that the combination seemed to be the source of the worst odors.  Ultimately, I may have to change to acrylics because I suspect I have become sensitized to oil painting elements that could give me trouble in the future. We’ll see.

In the meantime, I’m having an exhaust fan installed in the studio and will turn it on overnight during the cold season as the heat turns off. I will also use it during the day if I detect anything that feels dangerous. I never use turpentine, which is, according to Gamblin, the real source of toxicity in oil painting. I use only Gamsol odorless mineral spirits, and those I only use for cleaning brushes. I keep the containers closed when I’m not using them and will further my efforts to keep them from off-gassing from rags, etc. The odorless mineral spirits are not totally non-toxic (and not totally odorless, either) but still they can cause problems.

So, I’m issuing this warning for anyone doing a search on flake white, cremnitz, and even some underpainting whites: beware. They can cause problems, particularly if combined with an alkyd medium. A pretty good discussion of studio toxicity can be found on the Gamblin website, although Gamblin has a vested  interest in prmoting its own products as safe.

On a happier note, we delivered the quilting frame to its new home. I even found the installation manual (one flat sheet of paper, photocopied, from 1992). The frames fit nicely into the Honda, which we patted and praised for its excellence performance and perfect size.

–June