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Raising Backyard Chickens in Rosamond/Mojave



The California Department of Health Services (CDHS) has investigated dioxin contamination in the Rosamond and the south of Mojave areas. Dioxins are a group of 17 toxic chemicals. Dioxins were found in eggs from chickens that ate food directly from the ground. Although the health risks from eating eggs from chickens raised in the Rosamond and south of Mojave areas are small, CDHS feels it is important to inform you of the possible health risks.



What did the testing of the eggs from chickens in Rosamond find?

In the late 1980s, CDHS collected eggs from backyard chickens raised on soil in and near Rosamond. The results were:


South of Mojave: Eggs from two locations in the area south of Mojave contained high levels of dioxins. The levels were between two and seven parts per trillion (ppt)*. If a person ate three to four of these eggs a week for a lifetime (70 years), the risk of developing cancer would be about one in 10,000. This means that one out of every 10,000 people who ate the eggs would develop cancer sometime during their lifetime. In 1989, residents living very near metal recovery sites in the south of Mojave area were advised not to eat or sell eggs from chickens raised on soil.


Rosamond:  The eggs from chickens raised on the ground at four locations in and near Rosamond contained lower levels of dioxins than the eggs from the area south of Mojave. The Rosamond eggs had dioxin levels of 0.4 and 0.9 ppt.* In 1989, Rosamond residents were advised to limit their eating of backyard eggs to three or four eggs per week.


What about eating eggs from chickens raised on the ground now?

The south of Mojave/Rosamond testing was conducted in the late 1980s. Dioxins stay in soil a very long time. If testing was done today, the amount of dioxin found in eggs would probably be the same. Recent studies have also confirmed that dioxins can harm human health. Residents should continue to follow the 1989 advice.


What has been found in other areas of California?

CDHS has tested for dioxins in eggs from chickens raised on soil at homes in other, mostly rural, areas. These results showed:

        Eggs from all of the areas with former industrial sources of dioxins (the South of Mojave area, Oroville, Stockton (Boggs Tract), and Rosamond) had higher levels than eggs from an area with no known industrial sources (Nevada County).


        Levels of dioxins in eggs from chickens raised on ground in an area with no known dioxin sources (Nevada County) were five times higher than grocery store eggs (generally raised above ground).


How can I reduce the health risk from dioxin contamination in backyard chicken eggs? For those who want to continue to eat home-produced chicken eggs from chickens raised on soil, you can reduce your health risks by:


        Eating only the egg white;

        Removing the fat from chicken meat 


        Changing your chicken raising practices; 

        Enclosing chickens in a coop or pen; 

        Having a barrier such as cement, gravel or straw between the chickens and the ground; 

        Removing backyard dioxin sources.