This is true according two several reliable sources, including this one such as Harvard health publishing, and the New York Times. heavy metals have been found in dark chocolate, 43% exceeded the acceptable levels of lead, and 35% exceeded cadmium level, according to the study based in California law. however it is slightly misleading because it makes it sound like it is the manufacturers are putting lead in the product when in reality cocoa can absorb metals through the soil or well-being harvested, so it is rare to find any sort of dark or pure chocolate without heavy metals in it.