Study finds heavy metals in 28 popular dark chocolate bars

SEATTLE — Dark chocolate has a reputation as a relatively healthy treat, but research showing some popular bars might have potentially unsafe levels of heavy metals has many questioning how safe the treats really are.

Consumer Reports tested 28 popular dark chocolate bars from Seattle’s own Theo Chocolate to Trader Joe’s, Hershey’s to Ghirardelli, and even smaller brands such as Alter Eco and Mast.

The study found cadmium and lead in every single bar.

With Valentine’s Day around the corner, Consumer Reports last month called on chocolate makers to commit by Feb. 14 to reducing levels of heavy metals in their bars. The letters were sent alongside a petition with nearly 55,000 signatures.

With no federal limit set on heavy metals in foods, researchers used California’s limitations on lead and cadmium, the most protective in the country, to determine which chocolates posed the most risk.

California’s daily maximum allowable dose levels (MADL), set by Proposition 65, require businesses to provide warnings to Californians if a product leads to toxic chemical exposures that can cause cancer, birth defects or other reproductive harm. The limits were set for lead starting in 1988 and cadmium in 1997.

For 23 of the chocolate bars Consumer Reports tested, eating just 1 ounce exceeded California’s limits of 0.5 micrograms per day for lead — or about 1% of the weight of the average grain of sand — and 4.1 micrograms per day for cadmium.

One ounce of Theo’s Organic Extra Dark Pure Dark Chocolate 85% Cocoa chocolate bar, which is roughly one serving size, contained 140% of California’s maximum daily allowable dose of lead and 189% of the dose of cadmium, Consumer Reports found.

Consumer Reports also listed Theo’s Organic Pure Dark 70% Cocoa as having high levels of both.