Duke of Pearl - Posted - 09/20/2010:  11:44:54

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Well, since I don't really have time to hang much on the Hangout, this archived thread which generated comments on shell toxicity only just came to my attention: banjohangout.org/archive/156329. This current response was also just posted as an "Off Topic" thread, but since it's information every builder shoud be aware of am replicating it here for maximum readership.

As pointed out in the referenced discussion there are unending mentions in craft and luthiery literature referring to the supposed "toxicity" of nacreous shell dust, but inevitably these are completely lacking either direct primary evidence or support from published medical studies. In other words, the only "support" for such claims are anecdotal and usually second-hand (stories, gossip, and rumor).

As an excellent example of how these urban myths are passed along, the above thread mentions the famous and now deceased luthier J.W. Gallagher as having suffered from facial skin cancers caused by M.O.P. and abalone shell dusts; but it must be noted that this is a claim being passed along by another luthier, who quotes a comment made by Chet Atkins, who assumedly heard it from Gallagher while visiting his shop.

I'm not familiar with any specific medical details of Gallagher's case, but an almost identical story had circulated for years about the late inlayist Hascal Haile, who claimed that because of prolonged exposure to shell dust he had "suffered deep and disfiguring facial burns, necessitating plastic surgery" (as per an article appearing in the September 1979 issue of Pickin' magazine).

On contacting Mr. Haile he insisted that the information was based on "a whole week's worth of lab work done on [his] case at Vanderbilt University", but after numerous calls I was unable to locate anyone there who agreed with him! A letter sent to me by his physician (F. Tremaine Billings, M.D.) on Nov. 6, 1979, states: "None of us here believe that the dust from the work Mr. Hascal Haile does is causing his problem. We all feel that he picks his skin, pulls hairs, picks scabs off and generally is somewhat manipulative of his skin. Many people use the same material that Mr. Haile does without jeopardy. I would say that if you keep the dust down, have your room well ventilated and perhaps keep a little moisture, so that the dust is not too thick you will do well; particularly after your use of the grinding machinery be sure to wash yourself well and do not pick at your skin."

During my 43 years in doing inlays and commercially processing shell for the industry I've spent countless hours tracking down stories such as this, but not a single one has ever produced hard evidence that shell was the causative agent in any of the rumored sicknesses or deaths. I've probably inhaled and been exposed to more shell dust than anyone on the planet, and it's always been a major health concern that I not be doing long-term damage to any body parts. In 1977 I was able to get extensive testing done (by one private and one government lab) on all types of shells, including different parts of each shell. The results found NO evidence of poisonous or toxic substances, including: cyanide, bismuth, arsenic, radioactive isotopes, silicone (in its free SiO2 state), lead, mercury or any other heavy metals, in spite of the fact that each of the above (as well as others, such as "apache gas" or glucamite) have been claimed as being released during the working of shell.

This is not to say that shell dust can't be dangerous. But the real danger is more physical than chemical. The dust acts as a strong desiccant (sucking moisture from skin and mucous membranes), and is hard to wash off completely; dust in the lungs can cause lesions to the air sacs (alveoli) and a resulting scar tissue condition known as fibrosis, scars which can also become infected; the dust isn't dissolved by water or body fluids, so can eventually accumulate to dangerous levels. It can also contribute to nose bleeds, corneal scratching, damage to nasal cilia (the tiny hairs which help filter and propel mucous and particles outward and away from the lungs), initiate (rare) protein allergies, and transport infective materials present on raw shells (remnants of rotted organic matter).

But none of these issues involve actual toxins or poisons, and are problems associated with many other chemically inert dusts having sizes in the nanoscale range. As Frank Ford correctly points out, breathing any sort of fine dust is unhealthy. Work outside, use a fan or vacuum, and if it makes you feel better wear a decent dust mask (although not necessary if the above tips are followed -- a mask also interferes with being able to blow dust away from the cut while sawing).

For more detailed information, see "Is Shell Dust Hazardous" in Guitarmaker #16 (June, 1992).

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Edited by - Duke of Pearl on 09/20/2010 12:40:52

dickinnorwich - Posted - 09/20/2010:  11:58:39

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Chuck:
Maybe us war babies of the class of 1943 are just tougher than the rest of the wimpy kids coming up.
Seriously, a great post. Thanks, Dick//

Frisco Fred - Posted - 09/20/2010:  12:25:14

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Duke Of Pearl,

You really spent some time in relaying all the investgative work you've done.....Thanks.

I have heard wood workers describe very similar health hazards. There are also certain metals that are toxic when worked/machined but I'm not sure if the outgassing or dust. Dust sounds more plausible.

Once again, thanks for your contribution.

banjer5 - Posted - 09/20/2010:  12:49:04

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I really appreciate the post from Chuck and I might add that I've been a customer of his from long ago. A fair amount to MOP dust has been in my environment from when I started attempting inlay and I have had no known bad effects from it.

Fred

Duke of Pearl - Posted - 09/20/2010:  12:57:43

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Thanks! Regarding Frisco Fred's comment that

quote:

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There are also certain metals that are toxic when worked...

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this introduces another factor, for anyone using rotary discs or saws when cutting up whole raw shells. Especially when using hard rubber friction-cutting blades containing abrasive particles (such as carborundum or diamond) metals, adhesives, and other substances are released as the saw wears down and these elements can themselves create problems when inhaled (such as "metal fume fever") which have nothing at all to do directly with the shell being processed.

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Edited by - Duke of Pearl on 09/20/2010 12:58:30

beegee - Posted - 09/20/2010:  13:00:35

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Toxic or not, when I first started building banjos in Florida in 1972, I ground abalone shells in my workshop. The first time I got really sick-nausea, dizziness, fever, disorientation. I didn't connect the symptoms with shell-grinding. The 2nd time, I thought this weird. The 3rd time, Idecided not to grind anymore shell. So, I don't know if it was toxic, but my allergic reaction was enough to convince me to buy my shell blanks pre-sized.

sunburst - Posted - 09/20/2010:  13:01:23

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!Cough! !Cough!
Thanks, Chuck (cough), I feel much better now!
!Cough! !Cough!...

For the record, the Duke showed no apparent damage from playing this pearl encrusted banjo of mine, and I managed to inlay it with no apparent damage too.

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Edited by - sunburst on 09/20/2010 13:10:01

Duke

Deaf Lester Crawdad - Posted - 09/20/2010:  13:14:19

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quote:

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Originally posted by Duke of Pearl

As pointed out in the referenced discussion there are unending mentions in craft and luthiery literature referring to the supposed "toxicity" of nacreous shell dust, but inevitably these are completely lacking either direct primary evidence or support from published medical studies. In other words, the only "support" for such claims are anecdotal and usually second-hand (stories, gossip, and rumor).

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Bingo. While you don't want to be inhaling significant amounts of shell dust (or any dust) if you can avoid it, the shell dust itself is non-toxic.

When I was cutting the several thousand 2mm dots to do the "Galaxy" resonator inlay pattern on this banjo I *did* cut them underwater to prevent spreading the dust all over my shop, but that's not normally practical.

snavely.deviantart.com/gallery/#/d2s42aw

~Pete

uncle.fogey - Posted - 09/20/2010:  13:26:55

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Thanks,
This is great information - always good to know that I'm not slowly killing myself. I have never been able to grind abalone shells without a water grinder - the heat destroys the shell, so I have just given up trying to grind it down myself. Cutting inlays from pre-thicknessed blanks with a jewelers' saw, which is what I do now, creates almost no dust at all - I blow it off. MOP dust has never been a problem for me - I wish I could say the same for polyester resin, muriatic acid, denatured alcohol, dust from exotic wood species (I just had a 2-day sneezing problem from macassar ebony, and Honduras mahogany dust makes me really sick) and lacquer fumes.
Plus, I cut my finger down the middle with a bandsaw and I'm lucky to still have it. It will be another year before it's as good as it will get.

MOP is the least of my problems.

Duke of Pearl - Posted - 09/20/2010:  15:16:09

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We've always done a lot of our processing dry but the secret to not scorching shell is to use coarser grit stones/wheels, plus a lot of pressure so that material is removed quickly before heat can build up. Of course, since we supply finished blanks, I'd have to encourage everyone not to try this at home!

rudy - Posted - 09/20/2010:  18:26:25

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quote:

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Plus, I cut my finger down the middle with a bandsaw and I'm lucky to still have it. It will be another year before it's as good as it will get.

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uncle.fogey,
As a public service could you elaborate?
I'm not trying to sideline the topic, but whenever I hear thing like that I'm always interested in the "how and why" and more importantly, what did you learn to prevent similar or worse mishaps in the future.

steve davis - Posted - 09/20/2010:  19:01:34

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I have heard that there is arsenic in shells.

Deaf Lester Crawdad - Posted - 09/20/2010:  19:49:04

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quote:

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Originally posted by steve davis

I have heard that there is arsenic in shells.

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In a sense, there probably is a bit; because the critters that secrete the nacre strain the materials they use (mostly limestone) out of the seawater that surrounds them, and there are trace amounts of practically everything you can imagine in seawater.

Gold, for instance, is commonly found in seawater; but in amounts normally too small to detect; just as any arsenic in the shell would be too little to have any effect on the guy cutting the pearl.

Just don't inhale the dust and you'll be fine.

~Pete

steve davis - Posted - 09/20/2010:  20:00:00

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They went to cutting pearl buttons underwater.

grizzly1 - Posted - 09/20/2010:  20:40:49

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I might suggest the issue isn't if the shell dust is "toxic", it should be "will it damage your lungs over time". If we're talking poisoning over time versus mechanical damage over time, is there a functional difference?

Duke explained: "dust in the lungs can cause lesions to the air sacs (alveoli) and a resulting scar tissue condition known as fibrosis, scars which can also become infected; the dust isn't dissolved by water or body fluids, so can eventually accumulate to dangerous levels."

I spent time as an ICU Nurse caring for end-stage pulmonary fibrosis patients on ventilators, not a fate I would wish on anybody. Before I was a Nurse, I built Aluminum fishing boats and did a lot of grinding and welding without respirators because they were hot, and I thought I was tough. Now I wish I hadn't

I suggest we keep things that cause fibrosis out of our lungs, including shell dust.

Great thread

The Pope - Posted - 09/20/2010:  21:25:37

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Chuck knows...

Duke of Pearl - Posted - 09/20/2010:  22:41:12

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The issue is exactly whether or not shell dust is toxic, in order to distinguish real medical information from fable about actual and not imagined dangers. It does absolutely no good at all to initiate safeguards against "dangers" that don't really exist, while continuing to work unprotected against the real medical insults. You can't offer solutions until the problems have been accurately defined.

As far as the arsenic question, although no more than very tiny trace amounts are present in ocean pearl oyster shell (Pinctada sp.) and abalone (Haliotis sp.), it's interesting to note that the eating of shellfish such as lobster, shrimp, abalone, etc. temporarily increases the urinary excretion of arsenic in humans. As arsenic is used to impart color in glass work, it seemed possible that it might also be used by a shellfish to give color to the shell, but this seems not to be true. The human body secretes arsenic rapidly as long as the levels absorbed aren't too great, but it is accumulated in hair, nails, and sometimes skin (most noticeably in the neck, eyelids, and nipples), causing these tissues to become bronzed in color. Although breathing shell dust may produce in some people apparent symptoms of heavy metal poisoning, poisoning by arsenic would also include (besides the tissue discoloration) such additional signs as frequent nose bleeds, bleeding gums, weight loss, brittle nails, garlicky breath, a tingling sensation in the toes or fingertips, and loss of hair. As far as we know, this syndrome does not occur with shell workers (as scruffy as they may appear!).

Deaf Lester Crawdad - Posted - 09/20/2010:  23:03:34

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quote:

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Originally posted by Duke of Pearl

As far as we know, this syndrome does not occur with shell workers (as scruffy as they may appear!).

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Hey!

I resemble that remark!

~Pete

Ks_5-picker - Posted - 09/21/2010:  06:34:22

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en.wikipedia.org/wiki/Stuart_Mossman

Stuart Mossman was another who had problems with dust.By his own admission,he was not careful enough early in his career and it shortened his life considerably.You just have to use caution.

Banjophobic - Posted - 09/21/2010:  07:48:13

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Maybe its better to let folks think shell dust is 'poisonous', since they may be more lackadaisical if they find out its not a poision material-. Folks who repeatedly are exposed to, and breath, MOP dust, are at risk for a host of health liabilities. Yes, its an urban legend that its akin to arsenic or other such material. But it IS dangerous stuff to breath in fine powder/dust form, over long periods. Be smart and wear a mask,vacuum the dust as you cut/grind wet it and or combinations of all three.

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Edited by - Banjophobic on 09/21/2010 07:50:21

farmer bob - Posted - 09/21/2010:  12:16:49

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Back when I was in the chicken business we fed oyster shells to the birds. We would get them in 50 pound bags and dust would fly everywhere. Never was a problem and we never thought much of it. Today I am notorious about avoiding any kind of dust.

BTW a 50 pound bag of oyster shell contains a zilloin 1/4" chips of shell enough to make a lifetimes worth of dot inlays. I have not bought any in 15 years but it must still be very cheap...

10 miles down the road at the bay we have a town called Shellpile NJ. Pretty cool place as the name implies there are mountains of shells. Enough shell to supply the worlds inlay needs for the next 1000 years... Bob.

stanger - Posted - 09/21/2010:  12:35:59

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I'm not prepared to argue with the Duke- his knowledge of shells, their properties, and all is encyclopedic.
But back in the early 90's, Steve Carlson had a shell cutting operation going for a while, and I knew a couple of his workers. Some developed sensitivity to the shells, some didn't.

I tend to think that the toxic reactions I've heard about for so long are more likely due to the critters that once lived in the shells, not the shells themselves. It's a well known fact that some people are highly allergic to shellfish, especially abalone and scallops. Those with very high sensitivity could have allergic reactions similar to the folks who are allergic to peanuts, and could go into anaphylactic shock from the smallest trace of the shellfish left behind in the shells.
regards,
stanger

Deaf Lester Crawdad - Posted - 09/21/2010:  13:38:53

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quote:

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Originally posted by farmer bob

Back when I was in the chicken business we fed oyster shells to the birds. We would get them in 50 pound bags and dust would fly everywhere. Never was a problem and we never thought much of it. Today I am notorious about avoiding any kind of dust.

BTW a 50 pound bag of oyster shell contains a zilloin 1/4" chips of shell enough to make a lifetimes worth of dot inlays. I have not bought any in 15 years but it must still be very cheap...

10 miles down the road at the bay we have a town called Shellpile NJ. Pretty cool place as the name implies there are mountains of shells. Enough shell to supply the worlds inlay needs for the next 1000 years... Bob.

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Alas: Pearl oysters are different critters.

~Pete

Duke of Pearl - Posted - 09/21/2010:  14:08:15

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Carlson's operation at the then new Gibson Montana division plant was my old operation which they had purchased. I moved it all back there and spent a month setting it up and hiring/training workers, and Gibson's (short-lived) "Erika" division was born.

You're correct about the dust issues. Raw shells contain 2 potential sources of organic contaminates: the often heavy encrustation of tube worms, boring clams, boring sponges, coralline algae, and other things which die and decay on the shell once it's removed from the sea; and remnants of the harvested animal's flesh left clinging to the interior of a shell. Buying fresh raw shell at the waterfront is a grossly odiferous and maggoty task! This decomposed bacteria-laden material most certainly creates both infection and protein allegy risks for anyone handling uncleaned whole shell, and poses far greater dangers than to those just cutting inlay from processed materials.

In a small shop, working with commercially prepared materials generates only a minimum amount of waste or dust, not enough to bother most people, even those who specialize in doing inlays professionally. Exposure to dust (of any kind) is certainly not good for anyone already suffering from asthma or emphysema, or for habitual smokers whose respiratory system is already seriously compromised. A smoker's main concern isn't going to be the breathing of a small quantity of shell dust! Severe reactions to a tiny amount of shell dust is atypical and almost always due to a specific personal allergy or other medical problem.

One so-called shell dust fatality I was able to track down in 1976 was of a woman who cut shell professionally for ornamental uses in the Kon-Tiki chain of restaurants in California and Florida. In the popular press, her death was attributed to massive shell dust inhalation. According to her physicians (Dr. Neil at Navapache Clinic and Hospital in Showlow, AZ, and Dr. George Bondi at St. Luke's in Phoenix, AZ), shell dust was not at all a factor, except possibly as an aggravant, to one of her many chronic conditions such as diabetes, heart problems, collagen/vascular disease, Iatrogenic Cushing's Syndrome, and etc.

In 1970 or 1971 a man in Paramount, CA, reportedly died from breathing shell dust generated by the abalone shell mosaic table tops he had been making. Again, his personal doctor discounted the story, insisting instead that Mr. Johnson had been allergic to a large variety of substances, was bothered by the casting resin fumes he worked around, and died from acute emphysema and "other unrelated problems".

I could go on and on with similar cases, but most accounts of serious shell dust related health problems wind up not being traceable to anyone with medical authority, only to uneducated guesses, unfounded assumptions, personal anecdotes, second or third hand stories, and bad journalism.

Regarding the above reference to Stuart Mossman, the Mossman Guitars website has this to say: “In 1983 Mossman decided to sell the company after suffering from serious respiratory problems. Mossman began to feel that his breathing was being affected by years of inhaling sawdust, lacquer fumes and abalone shell fragments” (he died on March 4, 1999 from cardiac arrest at age 56). I'm not familiar with his actual health issues, but the medically proven dangers of resinous and chemically active sawdusts and lacquer fumes are in a risk class of their own, a far cry from the inert and medically insignificant factors associated with shell material; unfortunately, Mossman seems to have lumped all three together, causing shell dust to be perceived in the public mind as a threat equivalent to sawdust and lacquer fumes even though no evidence exists to support that opinion. Without hard scientific evidences, this was nothing more than an assumption and a guess, a self-diagnoses ("he began to feel...") made by a medically untrained layman and based on unproven generalities.

As pointed out earlier, proper safeguards can’t be devised until the problems have been accurately identified. Based on a false understanding of shell dust risks, old-time shell jewelry maker O.L. Frye (back in the 1960’s) went to extreme and unnecessary lengths to avoid contact with abalone dust: when working shell he completely coated all the skin on his head and arms with Vaseline Jelly, wore thick layers of clothing, long sleeved shirts, a head covering, and full face mask with filters; after work, he completely stripped to a new change of clothing, bathed and de-greased himself, and laundered all his work garments twice with the strongest detergents he could find.

This is panic-driven overkill based on rumor and ignorance. For anyone working with shell, they first need to honestly evaluate their own pre-existing medical conditions for anything that might be aggravated by dusts. Given a clean bill of health, adequate safeguards would then be nothing more than to employ one or more of the following: a close-fitting dust mask, an open-air work space, a nearby fan, a vacuum fitted with a fine mesh screen next to the cutting board, and a change of clothing and a good scrubbing of any dust covered skin. Since fumes and chemically active agents aren't a factor, there's no need for elaborate masks with charcoal pre-filters, or for an oilless air compressor feeding a positive-pressure full face mask. Keep it simple and comfortable, and enjoy working with shell!

Frisco Fred - Posted - 09/21/2010:  16:22:22

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The Medical people say:

"Genitics load the gun, their environment pulls the trigger"