Lead Poisoning
In a recent post, a new printer asked if it was safe to touch lead type. Considering all of the bad press that lead has gotten in the last few years, that’s a reasonable question…. one that should be clarified. According to “Metals Handbook” (which was one of my college textbooks) the lowdown on lead is this:
1. Lead in it’s metalic state cannot be absorbed through the skin. Thus it is perfectly safe to handle or touch.
2. Naturally occuring lead oxides that commonly form on metalic lead are also not absorbed through the skin. (Some oxides are though.)
3. Metalic lead can only enter the human system through ingestion or inhalation… you either have to eat it or inhale it.
4. Melted lead below 550 degrees F does not emit fumes. BUT once above that temp it can fume enough to be problematic. This temp varies from alloy to alloy.
5. The most common sources of lead posioning are from lead oxides used in paint; dissolved lead in water supplies from old lead pipes; overheated melted lead used in casting; lead dust from filing/grinding metalic lead; and inadvertent ingestion.
What this means in real life is that handling lead type is safe if you remember to wash your hands after you are finished, AND make sure that you don’t hold type in your mouth.
I’ve worked with lead type off and on for many years, and have cast lead type in hand molds. Recently I took a heavy metals blood test for work-related reasons…. and discovered that my blood lead levels were far below the national average. In fact, it was low enough to be considered “insignificant”. I take this to be proof enough that handling lead type is safe IF one washes their hands well after working with it.
I have run into this fear as well. I suspect the reloading community has as well given all the linotype metal they seem to be willing to buy.
It is VERY important to stress to people that the lead-antimony-tin alloys are not dangerous when handled with just a touch of common sense. The lead oxide naturally formed from those alloys is of insignificant danger when compared with the industrially-produced high-temperature oxides used in battery production and paint.
Wikipedia has a good diagram describing the oxidation process and critical temperatures here:
http://en.wikipedia.org/wiki/Lead_oxide
The more complex (higher temperature) oxides are less stable, and more prone to reactions, such as inhibiting the enzymes that create hemoglobin.
Winking Cat, thanks for sharing your experience and test results.
Thanks for the post. Touching type ain’t gonna kill anyone.
That is a wonderful post, winking cat - printing it for my naysayer friends. Thank you!
Someone once told me my 1924 walls under the paint layers were more dangerous than my type. I still use gloves when cleaning or handling it excessively, mainly as I like clean fingers. :)
Here are two interesting lead studies in industrial printing plants I found recently.
I would think they are different circumstances/exposure than most print shops handling letterpress, or home users like myself.
http://joh.med.uoeh-u.ac.jp/pdf/E43/E43_5_07.pdf
http://www.scielosp.org/scielo.php?pid=S0036-36341999000100006&script=sc...
Lead poisoning is indeed of great concern, and I would like to offer my services as a lead abatement specialist. All unwelcome lead type will be removed from your premises, and once ensconced in my type processing facility it will be handled with the utmost care and discretion. The older types, such as the tuscans, ornamentals, shaded and otherwise with all those nooks and crannies to collect dust and lead poison will be thoroughly cleaned with typewash and laid carefully in my cases to prevent the spread of disease. Every so often they will be removed from the case, set on end, coated with ink and then pressed into paper so as to keep any risk of the spread of lead poisoning at bay.
The newer types, such as Cheltenham Bold Extra Condensed and otherwise with all their poisonous attributes will be melted down immediately so as to avert their use and possible contamination of future generations of typesetters and their extended families. The molten lead will then be used in casting new types, ornaments and borders using special innoculated matrices guaranteed to stop the spread of the licentious and dubious lead poisoning. These new type renderings will be certified as safe as long as they remain in the possession of the type removal specialist, and are used for home and hobby use only.
Oh, thank goodness for selfless lead abatement specialists like Armchair Detective! I feel safer already.
Will you also be keeping our nation safe from the ravages of Wood Type?
There is in fact some concern about wood type. You’ve heard of the chestnut blight, dutch elm disease and perhaps the emerald ash borer. While wood type is not made from any of these woods, one can never be too safe. I can remove the threat of the spread of these ailments by simply removing your wood type. There is no charge for this service, and I will even pay the postage if you wish to ship.
Of greatest concern, however, is the dreaded disease of typohaulism. Everyone likes to take home a font of type now and then, but if left unchecked this habit can evolve into full-blown typohaulism. The classic symptoms are spending more time with type than with your family, being unable to account for time and money spent on type and, with an ever-increasing consumption of type, having blackouts where you can’t remember where your type came from.
At first, a mild consumption of type can be socially acceptable. Discussing type at a party or wayzgoose is a time-honored ice-breaker. In later stages, however, the typohaulic will shun the public and will spend more and more time with type in private, sometimes in dark and dingy basements or cluttered garages. If left unchecked, the typohaulic will alienate all others and may become a monomaniacal miserly hermit.
Do you sometimes wake up in the middle of the night in a cold sweat, thinking of the font that got away? Have you named your children after nineteeth-century type founders (George, Bruce, Thomas D., for instance)? It may be time to get some help.
You get lead poisoning from the dross when you smelt. The dross is formed from the paper dust and ink which forms a very fine powder or dross precautions should be taken when smelting scrap, smelters with hoods and extractor fans and I use a face mask. When I was an apprentice all the tradesmen went to the pub at lunch time and had three pints of best bitter to wash the lead out, a tradition which I keep alive!
Actually, the dangerous part of the dross is lead oxide, which forms at remelt temperatures, whatever else may be in it. Here in the US, milk was the recommended tonic for remelters. And maybe three pints was just part of a normal lunch.
I believe the required drinking of milk was the first self-imposed health regulation that the printing industry imposed. Initially, for those working with the processing of materials for metallic inks. It didn’t help.
Would anyone use asbestos anymore, or tobacco, or traditional solvents without knowing the possible consequences? Personally, no matter what anyone tells anyone, the only reason died-and-true letterpress folk support the notion that “lead is good” is because they are died-and-true letterpress folk. No one else in their right mind would.
Gerald
http://BielerPress.blogspot.com
I think it’s interesting that the “Milk as a preventative / remedy for lead poisoning” should pop up in this discussion. Many years ago I did a stint in Heavy Construction Painting…. removing lead paint from bridges and so forth. (it was a TERRIBLE job, one that I would not recommend as a carreer path) The old timers in that industry also swore by the Milk theory.
The company that we worked for actually did an experiment where they did lead tests on all of the workers, and then conducted surveys to determine if they drank milk or not. I’m sure that the results were not perfectly scientific, but they did seem to indicate that milk had some beneficial effects. The theory that I hold is that the calcium in the milk combines with the lead, and somehow aids in it’s expulsion from the body…. OR it does no good at all, and there were other factors in play.
BUT…. that is mostly a non-issue for printers since metalic lead is safe to handle as long as you don’t eat it.
Now… .about why lead was used in the first place: It actually quite simple. Lead’s melting point is low enough that one can use Brass matrices without melting them; it alloys well with other metals to make hard enough type; AND it was available at relatively low prices. Other metals also have these qualities, but they all cost a lot more.
Finally… is lead the BEST material for printing? No… not at all. I like lead type and use it for all sorts of things… but it’s not the best carrier of relief images. There are far better materials out there such as copper, steel, and a whole host of polymers.
Hi winking cat
Actually the reason lead was used in the first place is that it was very abundant in Europe way back when in the 15th century. Those folks knew an awful lot about metallurgy and mining, and the alchemists basically had worked the sucker to death trying to find the secret for transforming lead into gold (printing, me lads). They knew everything about it. Bit of tin and it was harder. Bit of bismuth and it wouldn’t shrink during casting (really important), etc. Plus, as Gutenberg discovered, use oil based paint and it would print well to a substrate, vellum or paper (a bit too early for polymers, alas).
Yea.
Gerald
http://BielerPress.blogspot.com
winking
Thought I should add this. Gutenberg’s ink formula, the secret of which he carried to his grave (but which we have discovered via our wonderful science), and which gave the brilliance to the printing of the Bible, was loaded with lead oxide, the crap that causes lead poisoning.
It’s used without restriction in parking lot paint, and on highways, and by the military, because it actually makes paint more durable. In this regard it has probably saved more lives than lives have been lost by eating paint chips.
Gerald
http://BielerPress.blogspot.com
Well you have got it half right. I will give you my thoughts now.. I have a degree from Cal Poly San luis Obisop, CA inn Printing Technology and Management. I am fith generation printer, now retired. If you knew how lead type was handled at the turn of the 20th Century, you would have a slightly different opinion. First the there was benzene for type cleaning. Then there was the practice of putting lead spacing material in your mouth to hold temporarily. The did not use nitrile gloves and any other protective equipment, just your basic shop apron and sleeve guard. Gloves were only used during a large form clean up. The degree of medical technology was one step above alchemy then. I have document proof of early death 50 - 60 years old from my own family. Again this was a problem at that time. Thankfully we are ore knowledgeable about materials and chemicals in 2011.
douglasc-
What a pile of horsepucky! A few decades ago this question was very prevalent and someone actually offered a $10,000.00 reward to ANYONE that could provide documented proof that any letterpress printer had ever died of lead poisoning. This offer stood for years and remained UNCLAIMED. I am not so sure that some of the solvents and other nasty things didn’t do their fair share of damage, but there simply is no documented proof that lead (other than possibly a bullet!) ever killed a printer.
Rick
My Dad spent 50 years handling lead and I even remember seeing him holding spacing material in his mouth. He retired in the 1980’s. He just passed away at 95 due to an accident. So there are exceptions. (He did laugh a lot and really enjoyed life, which I believe kept him alive so long)
To repeat, the problem isn’t lead, it’s lead oxides. Handling unoxidized typemetal is not a problem, but oxides can form on types stored in damp conditions, “type blight”.
It is at the high temperatures of remelting typemetal (rather than casting) that undisputably toxic material is produced in the regular course of work. Few are engaged in that.
At the turn of the 20th century, printers were far more likely to die of tuberculosis (or cirrhosis) than lead poisoning.