MITRA Forum Question Details

​For the benefit of beginners reading this, the body has no natural mechanism for eliminating lead so it's very important to avoid absorption. While I'm not a physician, I do know that firearms owners (especially those who make their own ammunition ) are advised to wear gloves when handling lead, so I would assume it's not a good practice to hold the lead portion of the stylus with bare skin. The type of soap used when washing hands apparently can affect how readily lead is taken up- some common detergents can speed absorption. There are special wipes and soaps for removing lead without promoting uptake. Some studies have shown that lead can absorb into the skin without immediately causing elevated blood levels, so blood testing may not always be a 100% reliable measure of overall lead burden in the body. It's probably not too difficult to mask off the portion of the stylus that makes contact with the hand. A paper drafting shield seems like a sensible measure, and make sure to control all shavings and dust from grooming the point.

Koo

When you have worked out a safe procedure, please let us know about the handling/aesthetic properties. It would think that seem that one would be constantly addressing the point on the lead and lead tin as compared to harder silver alloys. Even the dead-soft silver requires too much re-pointing for me.

I can find no specific reference to it, although to be honest, I have not been exhaustively searching for it. The problem is that, from my understanding, pewter was primarily an alloy of tin with a small amount of other metals added in a 1-15% proportion. These ranged from copper, bismuth, antimony, silver, lead, and others. Your lead-tin alloy may or may not qualify as pewter depending on the proportions. Additionally, quantitative x-ray fluorescence analysis has turned out to be more complicated that once thought so some of the alloy proportions given in earlier conservation literature may not be as conclusive as previously believed.

The greatest risk of exposure from elemental lead is through inhalation and ingestion, and less readily through skin absorption, but lead is so toxic precautions should definitely be taken particularly with hygiene. Therefore, if you handle the lead and your hands or surfaces become contaminated there is a risk of ingesting it if you're not washing your hands before eating, touching your face, etc. Dust may be produced from the use of the leads or from corrosion products (the white stuff you find on lead) that can flake off and contaminate hands and surfaces. Wearing gloves; working on removeable/disposable work surfaces; making a holder that will create a barrier beteeen you and the lead; and storing your lead supplies and finished pieces separately (and properly labelled as a hazard) from your other materials will help reduce your exposure. You can also wear a dust mask or respirator.

Below is the statement on exposure from the OSHA standard on lead which does not reflect that there is some slow absorption through skin:

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=10031&p_table=STANDARDS

"Lead can be absorbed into your body by inhalation (breathing) and ingestion (eating). Lead (except for certain organic lead compounds not covered by the standard, such as tetraethyl lead) is not absorbed through your skin. When lead is scattered in the air as a dust, fume or mist it can be inhaled and absorbed through you lungs and upper respiratory tract. Inhalation of airborne lead is generally the most important source of occupational lead absorption. You can also absorb lead through your digestive system if lead gets into your mouth and is swallowed. If you handle food, cigarettes, chewing tobacco, or make-up which have lead on them or handle them with hands contaminated with lead, this will contribute to ingestion.

A significant portion of the lead that you inhale or ingest gets into your blood stream. Once in your blood stream, lead is circulated throughout your body and stored in various organs and body tissues. Some of this lead is quickly filtered out of your body and excreted, but some remains in the blood and other tissues. As exposure to lead continues, the amount stored in your body will increase if you are absorbing more lead than your body is excreting. Even though you may not be aware of any immediate symptoms of disease, this lead stored in your tissues can be slowly causing irreversible damage, first to individual cells, then to your organs and whole body systems."

Natural Pigments makes lead points for use in metalpoint tecniques, and I have worked with it. Lead is very soft and hence does not require repointing using abrasive material to shape the point. Hence airborne partiles can be avoided by not shaping the point. Metallic lead is not readily absorbed through the skin. However, it is recommended to wear gloves while handling lead points to avoid picking up lead particles that may be then transferred to the mouth where it can be ingested, which is the primary route for exposure to lead. No other special preuations need to be observed other than standard hygiene practices which should be regularly practiced in the studio.