May 1998 Volume 20 Number 2

Health and Safety
Lead - The end

In all disciplines of conservation, we must be very careful about what goes into our mouths while we work.

This is my fourth column on lead hazards in conservation. We all know that lead, and for that matter, other heavy metal poisons, are really nasty players. They are toxic and accumulate in the body so that even small exposures can add up to potentially hazardous amounts. Periodic exposure to small amounts of lead, arsenic, cadmium, or mercury are possible for many conservators in the course of their work. Since we are exposed to some levels of these toxins in our natural and industrialized environment, it seems more than prudent to minimize our exposures to them while at work.

I've written before about the significance of HUD's (the US Department of Housing and Urban Development) Guidelines for the Evaluation and Control of Lead-Based Paint Hazards in Housing, hereafter referred to simply as Guidelines. The Guidelines are not copyrighted, the full publication is available on-line (at http://www.hud.gov/lea/learules.html) in the form of downloadable Adobe Acrobat files. The most relevant sections have been extracted and are included in the Conservator's Digest portion of this Newsletter.

Lead is not absorbed through the skin; most commonly it's ingested. Contamination on the skin ends up in the mouth. That's one of the reasons small children are so at risk, because everything ends up in their mouths. And that is why we must be careful about what goes into our mouths.

First and foremost: don't eat or drink in the studio! Nearly all of us do it. Stop now!

If you won't stop eating in your workspace, at least modify the rules. If you only have a single work area, set aside a clean area -- and keep it clean. If you have a separate office or non-treatment room, eat only there. Don't leave beverages open, exposed to any and all contaminates floating in the air. I know it is a joy to sit at the easel and sip your coffee. I did it for years. Stop it. Do you enjoy picking at a muffin or bagel or scone while doing paperwork in the morning? It doesn't matter if it is sitting on a clean napkin and loosely wrapped in plastic, if you are sitting in an area that could be contaminated, it is truly bad for you.

Other things that go into our collective mouths at work includes cotton and swabs used for "spit cleaning". Use only sterile materials and keep them clean. Keep cotton and swabs for "spit cleaning" in clean, closed containers.

Wash your hands often. Wash them before eating. Wash them before using the restroom. (Wash them after using the restroom, too, but that's not in the scope of this column.) Wash them before applying make-up, smoking, or fiddling with your contact lenses. Wash them again before going home. If you are working with an artifact that is particularly prone to expose you to heavy metals, wash your face before eating, applying makeup, smoking, or going home in the evening.

Why not buy a bottle of D-Lead® (or other similar product) Hand and Body Soap and put it next to your sink. It works like any liquid hand soap but, in addition to moisturizing your skin, it carries away any heavy metal contamination that might be on your hands or face. The correct way to use the soap is to wet your hands first, then apply the soap and lather so that it can wash the heavy metal particles away from your skin.

If an object you are working on might contain a heavy metal, either test it or treat it as though it were. A soft, white metal? Unless testing proves otherwise, assume it is lead. Friable paint and dust in a frame's rabbet? Unless testing proves otherwise, assume it is lead. An old taxidermy specimen? Unless testing shows otherwise, assume it has been treated with arsenic or mercury.

How do you test for lead? Probably the easiest (although it does not meet HUD testing standards) is to use LeadCheck® swabs. They can be purchased from a number of sources and in various quantities per package. They consist of a cardboard tube that has two glass ampules filled with reagents. You break the vials through the cardboard, mix the contents, and squeeze the test solution onto the white fiber end. The swab is rubbed on the suspect paint/metal/powder. Red indicates the presence of lead. If the test is negative, the swab is rubbed onto one of the supplied confirmation cards which have dots with a small amounts of lead to insure that the test is working.

But I think the best practice is to assume everything that might be lead, is lead, and to act accordingly.

In addition to good personal hygiene, this means: only using a HEPA (high efficiency particulate air-filter) vacuum to clean up. Sweeping with a broom or using a non-HEPA filtered vacuum are more apt to spread contamination than to clean it up.

Buy a bottle of the D-Lead® equipment cleaner or Antibacterial TSP Cleaner. Dilute the concentrate 1:10 and put it into a spray bottle. When wiping off a table top, use this instead of water or other cleaner.

Wear a lab coat or change clothes before going home at the end of the day. (I admit, I'm pretty lax about this one myself, but I'm changing my ways.) One of the dangers of exposure to lead is that you can easily wear it home, where it can contaminate your personal space and any children that might share that space with you.

When you launder lab clothing, use a detergent that removes heavy metal contamination. Guess what? D-Lead® again. Add the detergent after the washer is filled with water and the clothes are wet. Although the label says it is only for use in industrial machines, it is fine to use in smaller home washers. Use 2-3 oz. per washer load.

Wear a respirator with P100 filtration when a treatment might liberate respirable powders. Avoid these treatments if at all possible. If you need to wear a respirator to protect you from heavy metal particulates, you also need to wear protective outer clothing (including a head covering) and wash your face after removing the respirator.

When working on an artwork known to contain lead (or more correctly, but less clearly, not known not to contain lead) follow the recommendations that would apply if you were doing similar work as part of a lead abatement project. This is where the HUD Guidelines provide information that I've not seen anywhere else.

Put down two layers of polyethylene that extend 5' beyond the work area. Cleanup at the end of each day. Cleanup involves: picking-up the top layer of polyethylene and discarding it, HEPA vacuuming, wet cleaning with trisodium phosphate (or, better, D-Lead® equipment cleaner), and HEPA vacuuming again.

You might feel that I'm being a bit overly cautious, and perhaps I am. Most of the steps we all need to do to protect us from lead contamination are things we should do anyway. We shouldn't be eating or drinking in the studio. We should be washing our hands often. Other steps are minor modifications. When we clean up in the studio, we should use a HEPA filtered vacuum. We should use special cleaners to minimize heavy metal contamination when we wash our hands, wipe-off work surfaces, or launder our work cloths. And most importantly, we should be aware of the potential dangers associated with our work and make any decisions about personal protection based on information and knowledge.

D-Lead® products are manufactured by ESCA Tech, Inc.; Milwaukee, WI; (414) 351-5404. LeadCheck® swabs are manufactured by HybriVet Systems, Inc.; Framingham, MA; (800) 262-LEAD and are fairly widely distributed (hardware stores often carry them). Both are available from Lab Safety Supply, Inc.; PO Box 1368 Janesville, WI 53547; (800) 356-0783.

Chris Stavroudis is a conservator in private practice.