Lead and Cadmium Leeches into Brazilian Chocolate

You may want to be careful what you eat. Scientists have found that commercial samples of chocolate purchased in Brazil contain varying levels of lead and cadmium, which could both cause health problems-particularly for children.

Lead and cadmium are both naturally occurring metals. Yet they can cause health problems. Lead, for example, can cause abdominal pain, headaches and anemia in adults. In children, it can cause behavioral changes and language delay, among other problems. Cadmium can cause damage to several organs and also has estrogen-like effects that can disrupt some hormones.

Plants can naturally absorb these metals. Because chocolate is created with cocoa, which is harvested from plants, it's possible that these metals leeched into the chocolate that way.

The scientists first detected the metals by testing 30 milk, dark and white chocolate products bought in Brazil. Most were Brazilian brands, some of which were also sold in the U.S. In this case, the researchers found that dark chocolates had the highest levels of lead and cadmium, but all levels fell below maximum consumption limits from Brazil, the EU and the WHO. Yet the USDA recommends that the level of lead in candy should not exceed 100 nanograms per gram-and two samples topped this threshold by about 30 to 40 ng/g.

The scientists then calculated that if a child weighing 33 pounds ate about a third of an ounce of a chocolate each day, which is less than a quarter of a regular chocolate bar, the child would consume a maximum of 20 percent of the EU-suggested tolerable weekly intake of cadmium. That said, it's likely that only a fraction of the metals would be absorbed in a person's bloodstream.

Even so, the study points out the importance of understanding what a soil composition is like where particular plants are grown. Because these metals can leech into plants, it's crucial to take them into account when making agricultural decisions.

The findings are published in the Journal of Agricultural and Food Chemistry.