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plnelson
03-23-2019, 12:53 AM
I hardly ever use solvents. I have a small bottle of Gamsol and once in a while I might use a few drops for some special situation but mostly I'm solvent-free. I do underpaintings in acrylic or, more often in water mixable oils, and do all my cleanup in oil and Masters.

But I just saw another YouTube video where the guy was saying that Turpentine was more toxic than OMS and I wanted to find out what the evidence for this was.

Suppose you're toning a canvas with solvent-thinned paint and you use 5 ml of solvent. If that solvent is turpentine then all 5 ml is dumped in the air very quickly and you breathe it over a short time. But if it's OMS it evaporates more slowly so it takes longer but eventually all 5 ml is still dumped into the air you breathe. So if you're in the studio all day like many artists, aren't you still going to get the same amount of both?

In other words maybe in 6 hours you breathe as much OMS as what you would breathe of turpentine in 1 hour. But if you're in the studio for 8 hours then isn't that a distinction without a difference - you're still getting the full dose.

I've heard other people say that just because the odor is less for Gamsol and OMS doesn't mean they're safer and by the above reasoning I could see why. Does anyone have any actual hard facts on this? When I read the MSDS on Gamsol compared to (Klean Strip Pure Gum Spirits) Turpentine I was surprised that the LC50 on rats is WORSE for the Gamsol (5g/M3) than for turpentine (12g/M3)! Although in fairness to Gamsol it took it 8 hours to kill half the rats with 5 grams whereas the turpentine took 6 hours to do it with 12 grams, for the same volume.

(LC50 is the concentration that's lethal for 50% of the test animals)

RomanB
03-23-2019, 02:41 AM
It isnít 5 mg/m^3, it is just over this value. In other words, according to modern test protocol they were unable to kill test animals. As far as I understand, the problem is not in acute but in chronic toxicity. Artists seldom die of turpentine fumes still holding their brushes, but it is typical to develop Pakinson-like contition after chronic exposure to turpentine.

Gigalot
03-23-2019, 03:07 AM
It isnít 5 mg/m^3, it is just over this value. In other words, according to modern test protocol they were unable to kill test animals. As far as I understand, the problem is not in acute but in chronic toxicity. Artists seldom die of turpentine fumes still holding their brushes, but it is typical to develop Pakinson-like contition after chronic exposure to turpentine.
Have you a complete evidence, that artists' grade turpentine developed Pakinson-like condition to real artist into his real studio? (do not talk about benzene -toluene exposition during 50 years working time of printmaking men into printing facility!)

plnelson
03-23-2019, 03:07 AM
It isnít 5 mg/m^3, it is just over this value. In other words, according to modern test protocol they were unable to kill test animals. As far as I understand, the problem is not in acute but in chronic toxicity. Artists seldom die of turpentine fumes still holding their brushes, but it is typical to develop Pakinson-like contition after chronic exposure to turpentine.
The concentrations of the chemical in air that kills 50% of the test animals during the observation period is the LC50 value. (Source: https://www.ccohs.ca/oshanswers/chemicals/ld50.html)

... so why do you say they were unable to kill the test animals?

RomanB
03-23-2019, 03:32 AM
... so why do you say they were unable to kill the test animals?

Because there are marginal values, after reaching them a substance is considered minimally toxic. In animal testing, researchers estimate highest concentration or dose to start with and begin with it. If no or very few animals die, no further tests are needed. It is possible to conduct special tests with lower concentrations or higher doses, for example hazard class 5 is used in some countries, but to do so researchers must have solid reasons.

plnelson
03-23-2019, 03:41 AM
Have you a complete evidence, that artists' grade turpentine developed Pakinson-like contition to real artist into his real studio? (do not talk about benzene -toluene expossition during 50 years of working time men into printing facility!)
It would not be surprising given that turps are definitely neurotoxic: https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@[email protected]+204
(https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@[email protected]+204)

and Tad Spurgeon thinks it causes Parkinson's ... http://www.wetcanvas.com/forums/showthread.php?t=1450572

This article in Toxicology and Applied Pharmacology (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3621032/) finds the evidence of a connection between solvents intriguing but in need of more research.

but in doing a PubMed search I didn't see any direct connection between Turps and Parkinson's, specifically, although it's certainly bad for you in so many other ways that it hardly matters.

plnelson
03-23-2019, 04:06 AM
Because there are marginal values, after reaching them a substance is considered minimally toxic. In animal testing, researchers estimate highest concentration or dose to start with and begin with it. If no or very few animals die, no further tests are needed. It is possible to conduct special tests with lower concentrations or higher doses, for example hazard class 5 is used in some countries, but to do so researchers must have solid reasons.
You seem to be saying these are hypothetical estimations. How do you estimate an LC50 if no rats died? LC50 (and LD50) have a clear empirical definition. If you think these numbers are just made up you need to tell us why you think so and how they were arrived at.

The MSDS says that Gamsol is 50% lethal at less than half the concentration of turpentine. If you exposed two populations of rats to the "estimated highest" concentration of Gamsol and Turpentine, and none of them died then how would you conclude that the Gamsol is 50% lethal at less than half the concentration of turpentine? You can't. You can say it's "minimally hazardous" or something like that, but to attach an actual LC or LD number you need dead rats.

You seem to be saying we can ignore the MSDS because it's all just made up.

Gigalot
03-23-2019, 04:15 AM
It would not be surprising given that turps are definitely neurotoxic: https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@[email protected]+204
(https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@[email protected]+204)

I can't found actual artist, that was completely poisoned by turpentine in his studio. :crying:

Harold Roth
03-23-2019, 06:05 AM
You don't have to be completely poisoned or killed to be affected by a chemical. I don't know why anyone would argue such a thing.

Gamblin says Gamsol is "non-toxic when used as recommended." Not just plain "non-toxic." That means it is not harmless.

Less smelly--or in the case of spike--"nice" smelling (to some people)--is not a guarantee of safety. It just means that you either like the smell or it evaporates more slowly, the latter of which is the case with Gamsol. Some people like the smell of gasoline; that doesn't mean it isn't a neurotoxin.

I had my own little unintended Gamsol experiment. I was using it when I started oil painting to clean brushes. I had a small amount, like a 1/8", in a disposable tin the size of a measuring cup. I throw these tins out when I'm done for the day because I have a box of a thousand of them from a restaurant supply store. I forgot to throw this tin out at the end of the session. I slept next to my oil painting gear that night, probably about 5 feet away from that tin, in a room that is 550 square feet with 14 ft ceilings, so a LOT of space, and the window near me was cracked as usual. The next morning I woke up with a horrific headache and vertigo. It lasted all day. I felt like I had been poisoned. Only in the afternoon did I realize that I had forgotten to throw out the tin. The Gamsol had all evaporated from the tin by that time.

I couldn't smell it, though, so I guess I was really safe. /sarcasm

I occasionally use d-limonene to clean really messed-up brushes or a crusty palette. I do not find it is as penetrating as spike (there are other lavender essential oils I do like, like lavender Seville, which is made from L. stoechas instead of L. latifolia, like spike, and so has a different aromatic profile). D-limonene does not smell "pleasant" to me. It smells like what it is--a harsh solvent. This stuff can dissolve damar after all. And even though I use it for a few minutes and clean it right up and immediately take the rags to the dumpster, the next day I can still smell it in my studio, which is 350 square feet with 14 ft ceilings.

You can use whatever poison you want. People drink alcohol, after all, including me. But don't try to argue that alcohol is not a toxin and it never killed anyone or had neurotoxic effects or that people who don't want to drink it for health reasons are sissies. It just makes you look like you have no idea what you are talking about.

Gigalot
03-23-2019, 06:43 AM
Again, I can repeat my question: who was the artist, that was parkinsoned by using bona fide gum turpentine during his painting session process in his studio? Or who is an artist who seriosuly damaged his nervous system by using bona fide gum spirit turpentine (I use 10 years) during painting session in his artistic studio?
Anybody have exact answer? :confused:

DAK723
03-23-2019, 08:43 AM
Threads like this one make me think that perhaps it would be better if WetCanvas disappeared with the bankruptcy issues that are happening. :eek:

Actual experts - not internet wanna-be's - have answered this question for years now. Here's one answer that has been posted many times on this site:

Turpentine and Substitutes
By Michael McCann, Ph.D., C.I.H.

Turpentine is the classic solvent used by artists in oil painting and for clean-up. There are two basic types of turpentine: gum turpentine, distilled from the sap of pine trees; and wood turpentine, distilled from the pine wood. While wood turpentine is more hazardous than gum turpentine, both types are highly toxic by inhalation and skin absorption. Acute health effects include eye, nose, and throat irritation, narcosis (headaches, dizziness, nausea, confusion, rapid pulse), and at high levels, difficulty in breathing, kidney and bladder damage, convulsions, and possibly death. Chronic health effects include skin irritation and allergies, kidney and bladder damage, and nervous system damage.

I have seen many cases of allergic reactions and several cases of severe kidney damage in artists using turpentine. As a result, I recommend substituting safer solvents for turpentine.

The general turpentine substitute is mineral spirits (paint thinner, turpenoid, Varsol, Stoddard Solvent). Standard mineral spirits can contain about 15-20% aromatic hydrocarbons, giving mineral spirits their distinctive odor. The aromatic hydrocarbons are also the most toxic component. Acute health effects include eye, nose and throat irritation, and at high levels, dizziness, lightheadness, nausea, etc. Chronic health effects include skin irritation (but not allergies), and brain damage from long-term exposure to large amounts. Mineral spirits are not absorbed through the skin. In general, mineral spirits are less toxic than turpentine.

An even safer substitute are odorless (or deodorized) mineral spirits or paint thinner. The more toxic aromatic hydrocarbons have been reduced or removed, hence the milder odor. Since turpentine evaporates more quickly than mineral spirits, hazardous, high concentrations are achieved more quickly with turpentine than with mineral spirits. Turpentine is also more flammable than mineral spirits. Turpentine has a flash point of 95 F, meaning that enough vapors can form at this temperature to catch fire if a source of ignition is present. Mineral spirits, on the other hand, have a flash point over 100 F.

In conclusion, mineral spirits (especially the odorless type) are preferred over turpentine because of lower toxicity, lower volatility, and lower flammability.

Art Hazard News, Volume 11, No. 9, 1988

This article was originally printed for Art Hazard News, © copyright Center for Safety in the Arts 1988. It appears on CAR courtesy of the Health in the Arts Program, University of Illinois at Chicago, who have curated a collection of these articles from their archive which are still relevant to artists today.
It should be noted that since this article was published in 1988, some OMS makers are removing even more of the toxic aromatic hydrocarbons and they are even safer than before.

From Monona Rossol, M.S., M.F.A., Industrial Hygienist
President: Arts, Crafts & Theater Safety, Inc.

All the petroleum distillates are a mixtures of many hundreds of chemicals that boil between a particular range of temperatures. Related to this, of course, are their molecular weights. The "odorless" term is a chemists term that means only that the aromatic (benzene ring) distillate chemicals have been removed leaving primarily straight and branched chain hydrocarbons in a limited range of molecular weights. The solvents certainly aren't odorless as laypeople understand that term. If you can't smell them, see a neurologist.

These used to have TLVs in the range of 100 ppm. But the ACGIH changed it's procedure for assigning TLVs to petroleum distillates to a formula which involves average molecular weight. (See appendix H in the TLV booklet.) Some of the art material SDSs will imply there is no TLV for their product which should alert you to the fact that that company has a problem with their technical expertise. However, most of the pet distillates appropriate for painting will end up with TLVs of about 100 ppm.

That said, the safety and the ventilation rates for using these safely also depend on the solvent's evaporation rate. The faster they evaporate, the more gets in the air during use and the more cfm are needed to work safely with them. It is why I recommend a product called Gamsol (Gamblin paint) because there is a small fraction of high molecular weight hydrocarbons in the pet distillate that slows the evaporation. In addition, Gamblin provides all of the numbers needed to plug into the equation for setting ventilation rates. I rarely see this on the SDSs of the other products out there. So I'm saying, there may even be better products, but I haven't seen the numbers for any of the other solvents.

Summary: to evaluate the relative safety of various painting solvents you need the TLVs, evaporation rates, and other physical data such as flash points, vapor pressure, etc. Then it becomes rather cut and dried.

Stay completely away from any of the "natural" solvents. They are all vastly more toxic than the petroleum distillates.
In reading the initial post, the one obvious flaw in the reasoning is that there is an assumption that there is no air exchange in the room or that the concentration of particles doesn't matter - just the total number of particles over the entire evaporation period. Since there is always air exchange happening, the solvent that takes longer to evaporate will always have less in the room for you to breathe. So, no, you don't breathe in the same amount if you are in the room all day. You breathe more of the solvent with the highest concentration of particles in the air, and that is the one that evaporates the fastest.

Don

Gigalot
03-23-2019, 12:03 PM
Anybody know anyone artist, who was lethal poisoned or seriously damaged his lungs or nervous system by using artists' grade turpentine?

plnelson
03-23-2019, 10:20 PM
Anybody know anyone artist, who was lethal poisoned or seriously damaged his lungs or nervous system by using artists' grade turpentine?

Artists have a higher rate of death from cancer and several other causes than a matched cohort of the general population.
https://www.nytimes.com/1981/05/17/us/paint-use-is-linked-to-artist-s-cancer.html
... but given that artists are exposed to high concentrations of so many different toxic substances it's hard to pinpoint which particular one did them in.

This article is filled with lots of great links... OCCUPATIONAL EXPOSURE AS A PAINTER (https://www.ncbi.nlm.nih.gov/books/NBK304433/)

So we can't prove which particular toxin in his painting practice likely caused the lymphoma that killed Bob Ross at such a young age. Turps are actually less carcinogenic than mineral spirits - he used both and splashed them around like crazy. And many pigments are carcinogenic and not just the heavy metals (e.g., carbon black)

AnnieA
03-24-2019, 12:52 AM
Artists have a higher rate of death from cancer and several other causes than a matched cohort of the general population.
https://www.nytimes.com/1981/05/17/us/paint-use-is-linked-to-artist-s-cancer.html
... but given that artists are exposed to high concentrations of so many different toxic substances it's hard to pinpoint which particular one did them in.

This article is filled with lots of great links... OCCUPATIONAL EXPOSURE AS A PAINTER (https://www.ncbi.nlm.nih.gov/books/NBK304433/)

So we can't prove which particular toxin in his painting practice likely caused the lymphoma that killed Bob Ross at such a young age. Turps are actually less carcinogenic than mineral spirits - he used both and splashed them around like crazy. And many pigments are carcinogenic and not just the heavy metals (e.g., carbon black)

Hey, pinelson, thanks very much for the link to that first article. Although it didn't apparently specifically show which material caused the increase in the death rate among artists overall, among the group of artists, which included painters, sculptors and others, it was painters who had the highest death rates and one of the authors did specifically say that solvent use was implicated in the higher death rate in painters (although he didn't specify which particular solvent, and note that the article is from the early 1980s). An excerpt:
...Mr. Miller [a Public Health Service epidemiologist and the senior scientist in charge of the study] said that excess deaths from specific kinds of cancer were ''pronounced'' among artists, particularly painters. In the study, 568 of the artists were painters; the others were in various areas, including sculpting and silk-screening. The sample included 1,253 men and 345 women; 45 percent of the men and 70 percent of the women were painters.

In an interview, he said that ''the strength of the association of bladder cancer and leukemia in painters is startling'' and that solvents were implicated in the incidence of leukemia.

Excess deaths from leukemia, or blood cancer, and from bladder cancer were confined to painters in the study. Among them, Mr. Miller said, 13 bladder cancer deaths were found, as against the four deaths expected in a similar sample of white males in the general population. Nine deaths among those male painters were attributed to leukemia, as against three expected among the same number of persons in the population at large.

I never thought I'd think this, but watercolor is looking pretty good at the moment...

Gigalot
03-24-2019, 03:57 AM
In an interview, he said that ''the strength of the association of bladder cancer and leukemia in painters is startling'' and that solvents were implicated in the incidence of leukemia.
How many percentage the risk of cancer can be increased with artists profession? How many independent scientists agree with the one man, who gave this interview? Because one man can say anything by mistake, while scientific society have trusted opinion. (remember Tad Spurgeon, he can talk whatever he want!)

AnnieA
03-24-2019, 04:03 AM
In an interview, he said that ''the strength of the association of bladder cancer and leukemia in painters is startling'' and that solvents were implicated in the incidence of leukemia.
How many percentage the risk of cancer can be increased with artists profession? How many independent scientists agree with the one man, who gave this interview? Because one man can say anything by mistake, while scientific society have trusted opinion. (remember Tad Spurgeon, he can talk whenever he want!)
Alex, the article said that the man who made the statements about solvents being implicated in increased levels of various sorts of cancers was a Public Health Service epidemiologist and the senior scientist in charge of the study, so this wasn't a layperson making unsubstantiated assumptions. True, we don't know that these results have been replicated in elsewhere, and I personally haven't read the actual study itself. Still, if you read the article, there really were startling findings.

Gigalot
03-24-2019, 04:47 AM
Alex, the article said that the man who made the statements about solvents being implicated in increased levels of various sorts of cancers was a Public Health Service epidemiologist and the senior scientist in charge of the study, so this wasn't a layperson making unsubstantiated assumptions. True, we don't know that these results have been replicated in elsewhere, and I personally haven't read the actual study itself. Still, if you read the article, there really were startling findings.
I found only industrial painters risk of using toluene, benzene, styrene and chlorinated methylenes. Also asbest. Nothing about artistic materials except cadmium, lead and chromium pigments dispersed into the air of worker's places. Almost nothing about real artistic problems.

AnnieA
03-24-2019, 12:55 PM
I found only industrial painters risk of using toluene, benzene, styrene and chlorinated methylenes. Also asbest. Nothing about artistic materials except cadmium, lead and chromium pigments dispersed into the air of worker's places. Almost nothing about real artistic problems.
OK, Alex, but you appear to be saying there wasn't any research that found problems in artists (besides the one linked above). But were there any studies that disproved a link, or any studies done at all? A lack of studies may just mean there weren't any scientists looking into it. Perhaps they're focusing on larger populations, such as the industrial painters. Or perhaps there isn't any funding for such a specialized area.

plnelson
03-24-2019, 01:09 PM
In an interview, he said that ''the strength of the association of bladder cancer and leukemia in painters is startling'' and that solvents were implicated in the incidence of leukemia.
How many percentage the risk of cancer can be increased with artists profession? How many independent scientists agree with the one man, who gave this interview? Because one man can say anything by mistake, while scientific society have trusted opinion. (remember Tad Spurgeon, he can talk whatever he want!)
The NY Times article was a summary of a peer-reviewed published journal article and Miller was the lead author, so it's not just one random guy's random opinion.

Here's an abstract to more work by Miller : https://www.ncbi.nlm.nih.gov/pubmed/3963010
(https://www.ncbi.nlm.nih.gov/pubmed/3963010)
... but we're getting far afield of my original question. If the LC50 concentration for Gamsol is less than HALF what it is for a well known toxic solvent like Turpentine, why do we all think Gamsol is so much safer? Is it just because it's hard to smell? Is there any actual clinical or pathological data, research, or studies to show that Gamsol is safer?

TomM1
03-24-2019, 01:10 PM
I am more concerned with everyday aluminum contamination than turpentine.

AnnieA
03-24-2019, 01:20 PM
Here is a link to an exhaustive recent (2012) review of studies of the toxicologic effects of materials found to cause cancers in industrial painters: https://www.ncbi.nlm.nih.gov/books/NBK304433/ It's very long, but a couple of things that caught my attention are that: 1) they somehow found health affects among mothers exposed to paint materials, which caused me to wonder whether they were working in the industry or somehow had been exposed in some other passive manner (there were many additional link that I didn't follow and the answer is perhaps at one of the links); and, 2) the study found genotoxic effects (meaning the materials negatively affected people at the level of DNA) in both males and females. Scary stuff, but it may take a chemist/biologist to really understand it fully.

Yes, I know the typical exposure of an industrial painter is probably far higher than for those of us who work with artist materials, but it's worth a read anyway, as a cautionary tale.

plnelson
03-24-2019, 01:44 PM
... speaking of blood cancer, one reason I'm interested in this topic is that I'm an oil painter and I HAVE blood cancer. A rare myeloproliferative neoplasm called polythycemia vera.

It got me the 15 minutes of fame Andy Warhol promised all of us because the Wall Street Journal did a two page article about me that featured a photo of me at my easel . . .
https://www.wsj.com/articles/longevity-puzzle-a-medical-diagnosis-complicates-retirement-planning-1412958857

plnelson
03-24-2019, 01:58 PM
I am more concerned with everyday aluminum contamination than turpentine.
The epidemiological evidence linking turpentine to pathology is very strong. The epidemiological evidence for aluminum pathology is weak (but not non-existent). It's mostly in vitro but not so much in vivo. See:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131942/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651828/

... so I wouldn't ignore it, but it's not nearly as well-established as the toxicity of painting materials.

Keep in mind that many places, e.g., Jamaica, have lots and lots of aluminum in the drinking water because there is so much bauxite in the soil so if ingested aluminum were a major risk it would show up epidemiologically as a massive epidemic of neurological disease. But rates of dementia in Jamaica are comparable to the rest of the world: https://www.mona.uwi.edu/fms/wimj/article/3462

Dcam
03-24-2019, 02:23 PM
pl....would love to read the #22 article, but you have to sign in or subscribe?

Gigalot
03-24-2019, 02:43 PM
Industrial painters are airbrush workers, that widely exposed with aerosol paint, that made with toxic industrial solvents like toluene, styrene, xylene, benzene and glycols. Nothing to compare with artists material. Even Cadmiums and Lead pigments are in paint form and not aerosol. Nothing to inhale by artists there.

plnelson
03-24-2019, 04:00 PM
pl....would love to read the #22 article, but you have to sign in or subscribe?
It looks like they have it behind a paywall. But if you just want to see the picture of me at my easel that they used in the article you can type in the name of the article "the longevity puzzle" and do a Google image search and it comes up.

AnnieA
03-24-2019, 04:43 PM
It looks like they have it behind a paywall. But if you just want to see the picture of me at my easel that they used in the article you can type in the name of the article "the longevity puzzle" and do a Google image search and it comes up.
Here's a direct link: https://si.wsj.net/public/resources/images/BN-EY087_1009li_G_20141009162806.jpg

...you don't look very happy.

plnelson
03-24-2019, 06:27 PM
Here's a direct link: https://si.wsj.net/public/resources/images/BN-EY087_1009li_G_20141009162806.jpg

...you don't look very happy.

...the article was about me having an incurable form of blood cancer, so I thought it was best not to yuck it up too much. But many people live with this for decades and my numbers have been relatively stable except that I way overhproduce red cells and have to drop a pint of blood down the drain every month or two. It's one of the few diseases where bleeding the patient is the official treatment. I told them they should install a barbershop pole at the cancer center where I go but they didn't get the historical reference

TomM1
03-24-2019, 08:28 PM
The epidemiological evidence linking turpentine to pathology is very strong. The epidemiological evidence for aluminum pathology is weak (but not non-existent). It's mostly in vitro but not so much in vivo. See:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131942/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651828/

... so I wouldn't ignore it, but it's not nearly as well-established as the toxicity of painting materials.

Keep in mind that many places, e.g., Jamaica, have lots and lots of aluminum in the drinking water because there is so much bauxite in the soil so if ingested aluminum were a major risk it would show up epidemiologically as a massive epidemic of neurological disease. But rates of dementia in Jamaica are comparable to the rest of the world: https://www.mona.uwi.edu/fms/wimj/article/3462

But you won't mind if I don't use antiperspirants or eat food cooked in aluminum foil?
https://universityhealthnews.com/daily/memory/aluminum-linked-to-alzheimers-disease/

sidbledsoe
03-24-2019, 10:08 PM
you won't mind if I don't use antiperspirants or eat food cooked in aluminum foil?
I also don't use them, nor any aluminum cookware or containers.

AnnieA
03-25-2019, 05:32 PM
...the article was about me having an incurable form of blood cancer, so I thought it was best not to yuck it up too much. But many people live with this for decades and my numbers have been relatively stable except that I way overhproduce red cells and have to drop a pint of blood down the drain every month or two. It's one of the few diseases where bleeding the patient is the official treatment. I told them they should install a barbershop pole at the cancer center where I go but they didn't get the historical reference

pinelson, glad to hear you're OK! The treatment does sound medieval.:eek: No wonder you stay away from even Gamsol.

Harold Roth
03-25-2019, 06:42 PM
If the LC50 concentration for Gamsol is less than HALF what it is for a well known toxic solvent like Turpentine, why do we all think Gamsol is so much safer? Is it just because it's hard to smell? Is there any actual clinical or pathological data, research, or studies to show that Gamsol is safer?
IMO, it is precisely because it is hard to smell, especially for people who surround themselves with synthetic scents all day--in detergents, soaps, colognes, god forbid air fresheners, carpet cleaners, dryer sheets so it's on their clothes and bedding, even food (yes, they put synthetic fragrances in foods to make them taste better). These synthetics are so strong and so ubiquitous that they desensitize your nose.

plnelson
03-31-2019, 12:19 AM
As I mentioned, lo these many postings ago, I hardly ever use solvents, since I do underpaintings in w/m oils or acrylic, and clean my brushes with oil. But I keep solvents around for special situations.

Recently there was an amazing painting Cat With A Pearl Earring (http://www.wetcanvas.com/forums/showthread.php?t=1463828) in the main oil painting forum (check it out!) and the artist was describing how he painted the whiskers of the cat using a technique involving solvent.

I only steal from the best so I was giving it a try tonight and as soon as I opened up my Gamsol and dipped a tiny brush in it and started using it, the VOC meter on my Winix air cleaner, about 5 feet from my easel, went nuts. I have a small clip-on fan that blows across my easel and toward the Winix.
http://www.wetcanvas.com/Community/images/31-Mar-2019/21373-VOC.jpg
... normally only the green ("good") light is on. I get a sore throat after just an hour of exposure to Gamsol or Neo Meglip; other people get headaches. But to me Gamsol has no smell at all. (Lavender Spike and Citrus solvent, by comparison, are overpowering) So this is proof that just because the aromatics are removed doesn't mean you're not getting a lungful!

sidbledsoe
03-31-2019, 12:54 PM
Yes, a fan blowing directly across a painting will significantly increase the evaporation rate of any solvent.

A better method is to have a mild vacuum, positioned below the easel/painting , that exhausts outside, away from the studio.
I know of one artist who has this type of setup, Carol Marine.

Regardless of the relative smells, the OSHA PEL limit for Gamsol is much better than the limit for turpentine, something like 3 or 4 times lower, this coupled with the slower evaporation rate makes Gamsol much less toxic than either turp or spike.

Richard P
03-31-2019, 03:51 PM
After a few minutes I feel an occasional faint tickling in my nose when using Gamsol. I only use it for varnishing paintings though.