Did you run through your Valentine’s Day chocolates already? Or are they so special that you’re planning to savor them over the next week or two? Maybe you’re ambivalent about your chocolates– you love them, and yet, you have to wonder “how much lead am I willing to consume?”
Do your chocolates contain lead?
There are two ways to approach that question. The first is denial: “Not my chocolates! They’re too expensive!” The second involves steadfast scientific inquiry: “Hmm, what kind of studies have been done on this subject?” To be thorough, let’s take both approaches. Enjoy your chocolates while we search for answers.
Where did your chocolates originate?
Good luck figuring that out! Chocolate is unique because its raw materials –the cocoa beans–are produced in one part of the world while its final product–cocoa powder or chocolate–is manufactured and consumed in an entirely different part of the world.
In other words, it’s hard to “eat local” when it comes to chocolate. To begin with, you’d have to live along the “20th parallel,” a region that circles the globe just above and below the equator. It’s the only place cocoa trees will grow. Cocoa trees need even temperatures, year-round precipitation, and midges for pollination. (Midges are small flying insects that resemble mosquitoes.) Aside from the midges, the 20th parallel sounds like paradise. Hawaii, for example, has what it takes to grow cocoa. Yet, given the cheaper labor, the majority of the chocolate we eat comes from cocoa beans grown on small farms in Africa, mostly along the Ivory Coast, or small farms in Indonesia, Brazil, or some other Latin American country.
Once the cocoa beans leave the farm, they head north to be made into chocolate. Since the melting point of chocolate is 97 degrees Fahrenheit (just below body temperature), it’s a lot cheaper and easier to manufacture chocolate in northern regions, where the climate is cooler. Most chocolate is manufactured and consumed in Europe and the United States.
In an article on the multinational histories of chocolate, Julie Cidell and Heike Alberts describe the chocolate supply chain as having a “double disconnect.” The people who grow the cocoa beans, small farmers in developing nations, rarely consume the final product of their work. Chocolate consumers—those of us in the wealthier, developed nations–have little way of tracing back the origins of our chocolate to a particular country, let alone a particular farm.
While the origin of our chocolate may be murky, one thing seems pretty clear: the chocolate you are eating probably contains some amount of lead.
The lead contents of chocolate and the products it flavors are among the highest of all commonly consumed substances.”
William I. Manton, in the Journal of Agriculture and Food Chemistry. January 27, 2010
According to William Manton, a professor who specializes in tracing lead in our environment, lead may get into chocolates at one or more stages of the chocolate-making process. The cocoa tree may absorb lead from the soil and transfer it to the beans. If a particular cocoa producing country still uses leaded gasoline, lead from vehicle exhaust may settle on the beans while they are out in the sun, drying by the roadside. Lead contamination may also occur while the beans are being stored, transported, or made into chocolate.
A study in Nigeria supports the idea that natural growing conditions are not the culprit when it comes to lead in chocolate. Scientists found relatively small amounts of lead in cocoa beans taken from six different farms in a major cocoa producing region of Nigeria. Whereas high amounts of lead were found in manufactured chocolate products.
Where do your particular chocolates stand?
It depends. Do you like milk chocolate or dark chocolate?
If you like milk chocolate, you’re in luck. Since children are avid consumers of milk chocolate, the FDA periodically screens milk chocolate candy bars for lead. As part of the FDA’s Total Diet Study, the candy bars are randomly selected from various retailers and then analyzed. In the latest survey (2008), the average amount of lead detected was seven times lower than the FDA’s level of concern for children.
If you like dark chocolate, you’ll have to weigh known benefits against the probability that you are eating a bit of lead. Dark chocolate is far more concentrated than milk chocolate. As a result, the FDA identifies dark chocolate as the chief source of lead in chocolate.
Cidell JL, Alberts HC. 2006. Constructing quality: The multinational histories of chocolate. Geoforum. 37(6): 999-1007. doi: 10.1016/j.geoforum.2006.02.006. http://www.sciencedirect.com/science/article/pii/S0016718506000388
Manton WI. 2010. Determination of the provenance of cocoa by soil protolith ages and assessment of anthropogenic lead contamination by Pb/Nd and [lead isotope ratios. Journal of Agricultural and Food Chemistry. 58(2):713–721.
Rankin CW, Nriagu JO, Aggarwal JK, Arowolo TA, Adebayo K and Flegal AR. 2005. Lead contamination in cocoa and cocoa products: isotopic evidence of global contamination. Environmental Health Perspectives. 113(10): 1344–1348. doi: 10.1289/ehp.8009. Also available at: http://www.michigan.gov/documents/80091_164503_7.pdfEHPLeadcocoa.pdf
U.S. Food and Drug Administration. 2005 (revised 2006). Guidance for Industry: Lead in candy likely to be consumed frequently by small children: recommended maximum level and enforcement policy. http://www.fda.gov/Food/GuidanceComplianceRegulatoryInformation/GuidanceDocuments/ChemicalContaminantsandPesticides/ucm077904.htm