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Industrial pollutants find their way into the eggs of free-range hens


My household recently acquired three new chickens, bringing our roster to a total of six. We're keeping track of a draft pecking order and the number of eggs produced by Yolko Ono, Emily Chickenson, et al.

So I was fascinated by a chicken-themed Booster Shots post today.

According to Taiwanese researchers, eggs from free-range hens contain much higher levels of industrial pollutants than eggs from caged hens:

The researchers focused on two types of pollutants, polychlorinated dibenzo-p-dioxins and dibenzofurans (known collectively as PCCD/Fs), which are released into the environment by municipal waste incinerators, factories and other industrial sources. A report from the International Program on Chemical Safety says the chemicals have caused cancer, liver damage, problems with the skin and nervous system, reproductive problems and other undesirable effects in animals.

The researchers collected 60 free range eggs from farms in southern Taiwan and compared them with 120 eggs from caged hens that were purchased throughout the country. Then they measured the levels of 17 kinds of PCCD/Fs.

For the free range eggs, the levels ranged from 6.18 to 41.3 picograms per gram of lipid, with an average value of 17.5 pg/g. Levels for the caged eggs ranged from 2.85 to 19.8 pg/g, with an average value of 7.65.

The researchers speculate the free-range chickens pick up contaminants from soil, plants and insects and incorporate them in their eggs. Their study appears in the latest edition of the Journal of Agricultural and Food Chemistry.

Photo by bigbold

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