By Dr. Birgit Puschner, UC Davis School of Veterinary Medicine and
Maurice Pitesky, UC Davis School of Veterinary Medicine-Cooperative Extension

Dr. Brigit Puschner

Dr. Maurice Pitesky

In addition to all the destruction and inhalation of smoke associated with the recent fires in Northern California, one of the unfortunate legacies remaining are chemical contamination of land, soil and water.  The wildfire debris can include household hazardous waste (e.g. batteries and other electronic waste, paints, flammable liquids), building material (e.g. stucco, sheetrock, joint compound, asbestos siding and pipe insulation), pesticides, and fire suppression chemicals that may have been used.  For example, ash debris from the California wildfires from 2007 was found to contain heavy metals that could cause long term health effects with exposure at high levels.

Backyard chickens typically live off the soil and hence are at risk for exposure to some of the chemicals in the debris. Since backyard chickens are food animals with respect to egg and meat production, there is a risk that some of these substances may be ingested by chickens and deposited inside eggs which are then laid by the chickens.

Unfortunately, there is limited scientific data on this issue. To that point there are no controlled studies, to our knowledge, that have assessed whether many of these chemicals can be found in eggs following ingestion by chickens. In addition, withdrawal periods following exposure are also not understood.

What can you do?

The concern to human health is with respect to the consumption of eggs and poultry meat from chickens exposed to the above listed toxic debris as a result of the recent fires. Out of an abundance of caution: if you know or suspect that your birds were foraging in burnt areas, we recommend not eating eggs from those hens for the remainder of their life. 

In addition, in order to better understand the chemical contamination of eggs from hens living in areas impacted by wildfires we encourage people in affected areas to submit eggs to UC Davis for testing. Testing costs will be free.

For submission, please mail up to 6 eggs overnight to the following address:

UC Davis School of Veterinary Medicine
Attn: Dr. Maurice Pitesky
1 Shields Drive
VM 3B Room 4007
Davis, CA 95616

Please include the following information:

• Contact information
• Address where birds are located
• Number of birds in your flock

For further questions please contact Dr. Birgit Puschner or Dr. Pitesky.