If you have urban chickens (if you keep chickens in a city or town and they live on a small lot and are allowed to graze close to your house or your neighbor’s house), your best bet is to have your soil tested. If you have a pre-1978 home you should have your soil tested for lead and other contaminants anyway - (for the safety of children, pets and others using the home.)  (There are many hazard assessors to choose from, however here in the Portland, Oregon area I have had consistently good experiences using Net-Compliance out of Vancouver, Washington. )

A full home hazard assessment costs about $450 and I imagine that a hazard assessment of the exterior of your home and your soil would be less (possibly in the $200 - $300 range.)  They will do XRF testing of the paint on the exterior of your home  (& out buildings) and they will do soil samples (that they send to a lab) to test the lead content of your soil.  They might also do dust wipe samples on exterior surfaces if they think it is appropriate.

Because there are currently no standards regarding what amount of lead is considered safe for soil where chickens live, you will have to do your own research once you get the results.  However I would recommend at least using the Federal standards for safe play areas for children (400 ppm, expected to be lowered to 200 ppm soon) and if you’re serious about going non-toxic, possibly consider 40 ppm—the upper limit for naturally occurring background level of lead in uncontaminated soil1 as an ideal.

1 From “Protecting Children from Lead-Tainted Imports” Testimony by Dana Best,MD, MPH, FAAP on behalf of The American Academy Of Pediatrics before the Energy And Commerce Subcommittee On Commerce, Trade, And Consumer Protection,  September 20, 2007

Nicole Thomsen with the King County Childhood Lead Poisoning Prevention program in Seattle, Washington posted this response on lead-net 10/29/2008:

“I had a similar question about this recently.  The question came from an urban mother who is raising egg-laying chickens in their back yard for personal consumption (free-range). They live in a 100+ year old home and were concerned about lead poisoning.  While researching the egg question I found a journal article addressing such a topic (see attachment).  In short both the chicken tissues and the eggs can become contaminated.  In particular for the

egg, lead concentrates in the yolk first, then the shell, and then the whites.

In discussing this further with our state’s toxicologist it was agreed that the best thing to do would be to test the soils where the chickens spend most of their time.  If elevated you could move to testing the chicken.”

Used with permission

Nicole Thomsen, REHS

Childhood Lead Poisoning Prevention

Local Hazardous Waste Management Program - Seattle, WA