Taiwan Study Finds Higher Levels of Dioxins in Free-range Chicken Eggs
In a new study by scientists at National Cheng Kung University, researchers found that eggs from free-range chickens in Taiwan contain at least five times higher levels of certain pollutants than eggs produced by cage-fed chickens.
Their findings appear in the bi-weekly Journal of Agricultural and Food Chemistry.
Pao-Chi Liao and colleagues note that free-range chickens have continuous access to fresh air, sunshine, and exercise, in contrast to chickens that are confined to cages. Scientists suspect that free-range chickens may risk getting higher levels of exposure to dioxins, particularly polychlorinated dibenzo-p-dioxins and dibenzofurans, that are produced as byproducts of burning waste. These substances may cause a wide range of health problems in humans, including reproductive and developmental problems and cancer.
The scientists collected six free-range eggs and 12 regular eggs from farms and markets in Taiwan and analyzed the eggs for their dioxin content. Taiwan, they note, is a heavily populated, industrialized island with many of the municipal incinerators that release PCDDs and PCDFs. They found that the free-range eggs contained 5.7 times higher levels of PCDDs and PCDFs than the regular eggs. The scientists suggest that the findings raise concern about the safety of eating free-range chicken eggs.