Free Range Eggs may not be Healthy

Kathleen Blanchard's picture

Scientists have found pollutants in free range eggs, leading to suggestions that choosing eggs from chickens with fresh air, sunshine, and exercise may not be so healthy. Free range eggs that are supposed to provide healthy fats and more nutrients, but new findings show the eggs may be highly polluted.

Free range eggs were found by scientists in Taiwan to have five times the amount of pollutants compared to those found in eggs from caged chickens.

Researchers Pao-Chi Liao and colleagues think free range chickens might be exposed to environmental pollutants, especially potentially deadly dioxins or PCDDs and PCDFs.


Dioxins discovered in free range eggs can cause cancer through hormone disruption, immune problems and reproductive health issues. According to the World Health Organization (WHO), "Dioxins are a group of chemically-related compounds that are persistent environmental pollutants" that collect in the fatty tissue of animals and are "highly toxic".

Dioxins accumulate in the environment from the production of pesticides, herbicides, and incomplete burning of hospital and other industrial waste products. The pollutant found in high levels in free range eggs can occur from volcanic eruption and forest fires.

The toxins, of which there are 419, are found throughout the globe and are now showing up in free range eggs. Free range eggs in Taiwan, a heavily industrialized and populated island with many incinerators, were found to contain 5.7 times higher levels of PCDDs and PCDFs - also known as dioxins - than regular eggs. The findings suggest that free range eggs might not be so healthy after all.

J. Agric. Food Chem: DOI: 10.1021/jf100456b