“Life is like a box of chocolates, you never know what you’re going to get” – Forrest Gump used to say and this is particularly true when toxic heavy metals are found in the chocolate bar you are going to eat.
What happened in the USA?
Consumer report tested 28 dark chocolate bars for lead and cadmium levels. To assess the risk, California’s standard maximum allowable dose levels (MADL) was applied for lead (0.5 µg per day) and cadmium (4.1 µg per day). The results indicated that 23 products showed comparatively higher levels of lead, cadmium or lead and cadmium together, up to 2-fold higher than MADL.
Guilty Dark chocolate
Dark chocolate seems a healthier choice because of its higher flavonoid content and low percentage of sugar but it is richer of cocoa beans that, adsorbing cadmium and lead from the environment, can concentrate them in the final chocolate product. Unfortunately, heavy metals in food are a long and ancient story: just remember to arsenic in rice, cadmium in spinach, lead in carrots and sweet potatoes, and mercury in different fish species. Exposure to heavy metals is a great concern especially for some population groups, such as pregnant women and children. Indeed, high levels of cadmium and lead are able to impair brain and nervous system development, causing cognitive and behavioural problems. Moreover, they can accumulate over time in the human body, leading to detrimental effects on kidneys, lungs, bones, and immune system.
How is it handled in the European Union?
Yes, let’s come back to Europe. Here, the contaminants limit in the foodstuff is under the control of the Regulation No 2023/915. The maximum level allowed for cadmium changes depending on the amounts of dry cocoa solids contained in the chocolate product, ranging from 0,10 µg /kg for milk chocolate up to 0.80 µg/kg for Chocolate with ≥ 50 % of total dry cocoa solids. Interestingly, lead limits are set for different food products, including cereals, wine, and food supplements, but not for chocolate products.
What can we do now?
The main aspect we have to consider is the chronic exposure to heavy metals that, in this case, means the daily and high consumption of dark chocolate or chocolate derived products. Since lead and cadmium can be found in other foodstuff, a safer choice can be eating chocolate occasionally and choosing a chocolate product with lower percentage of cocoa beans. In addition, let’s not forget about quality. Low quality products are normally less controlled and tested compared to high quality ones leading to a higher chance of high levels of heavy metals.
Ps. It’s ok to forget all of that at Christmas time! Enjoy your chocolate 
