What's interesting is that cocoa beans tested had an average lead concentration of < 0.5 ng/g, "one of the lowest reported values for a natural food," the study points out. But, by contrast, "lead concentrations of manufactured cocoa and chocolate products were as high as 230 and 70 ng/g."
In fact, a team of American and Nigerian researchers found that lead levels in raw cocoa beans were 60 times lower than lead levels observed in processed chocolate products, the Chicago Tribune reports.
Talk about a worrisome statistic.
Researchers suspect that this lead contamination doesn't come from the producer but rather during the shipping and/or manufacturing of the cocoa beans into cocoa and chocolate products.
For example, they speculate that one source of contamination of the processed, finished chocolates might be atmospheric emissions of leaded gasoline.
"Because of the high capacity of cocoa bean shells to adsorb lead, contamination from leaded gasoline emissions may occur during the fermentation and sun-drying of unshelled beans at cocoa farms."
Regardless of the source of contamination, "there is no excuse for a product that is about to be consumed by children to contain lead, period," Dr. John Rosen, a pediatrician and lead program director at Montefiore Medical Center in New York City, told the Chicago Tribune.
Lead exposure can be quite dangerous, particularly to children. For example, it can lead to permanent developmental deficits. High lead levels can harm a child's ability to think, plan, organize and memorize, Rosen explained. "And lower levels of lead may produce intellectual deficits that are with a child forever."
Yikes, this is scary.
But, as I stated previously, you can still reap chocolate's anti-oxidant and other benefits by eating raw cacao beans.
Furthermore, as popular physician Dr. Joseph Mercola.com points out, you also can "derive a majority of these benefits by consuming blueberries, apples and grapes, and most vegeetables, including broccoli, greens and onions.