Epoch HealthCertain Dark Chocolates Contain High Level of Heavy Metals, Study Finds

Soil Contamination and Processing Methods May Contribute to Heavy Metal Presence in Dark Chocolate, Raising Health Concerns

A recent study published in Frontiers in Nutrition reveals that many dark chocolate and cocoa products sold in the United States contain concerning levels of heavy metals, particularly lead and cadmium. The research, conducted by scientists from George Washington University and ConsumerLab.com, analyzed 72 products over an eight-year period, identifying potential health risks associated with dark chocolate consumption.

Key Points:

• The study examined 72 dark chocolate and cocoa products sold in the US from 2014 to 2022
• 43% of products exceeded California Proposition 65 limits for lead
• 35% of products surpassed Proposition 65 limits for cadmium
• 97.2% of products fell below FDA interim reference levels (IRLs) for lead
• Organic-labeled products showed significantly higher concentrations of cadmium and lead
• Organic products were 280% more likely to exceed Proposition 65’s cadmium limit and 14% more likely to exceed its lead limit
• Trade certifications like Fairtrade and non-GMO did not significantly affect heavy metal levels
• Lead contamination may occur primarily during post-harvest processing, while cadmium is absorbed through the plant’s root system
• Cocoa trees can absorb heavy metals naturally present in soil or from environmental contamination
• Sources of soil contamination include livestock manure, wastewater irrigation, sewage sludge, metallo-pesticides, phosphate-based fertilizers, and atmospheric deposition
• Even low levels of lead exposure can affect the central nervous system, potentially causing cognitive decline and attention-related issues
• Cadmium exposure is associated with increased cardiovascular risk, atherosclerosis progression, and potential kidney damage
• The study questions whether the proposed benefits of cocoa outweigh the possible risks of heavy metal exposure
• Consuming multiple servings of contaminated dark chocolate could lead to excessive heavy metal exposure
• Other food sources of heavy metals include leafy vegetables, root vegetables, grains, marine fish, and herbal products

“We know chocolate is a plant that is particularly good at absorbing heavy metals from the soil and is grown in areas where there are heavy metals in the soil.”
– Leigh Frame, director of integrative medicine at George Washington University and co-lead of the study

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