Extensive biological lab-testing in Europe and the US with rats has shown that Cd can be carcinogenic, and potentially deadly when breathed in, or when found in large concentrations in the food those test animals ate. But I have never found the slightest bit of actual data to show that either Zn or Cd is dangerous if found in any of the products we physically touch (use and handle) in our daily lives. I have known people who are afraid to even touch products containing these elements because of the EU’s RoHS-Directive and laws similar to it, thinking that skin contact with such materials is dangerous. Such rumors are totally false and misleading. The only reason why warnings are made about items containing such elements is because of soil-contamination issues that might occur when such products are disposed of, which might then affect groundwater, etc., and thus get into the human body via the water or the food grown in those regions, etc.. However, please understand that it would take a huge amount of such contamination to actually affect peoples’ health in those areas. Please understand, too, that the greater risk is in Zn and Cd fumes, which are not good to breathe at all, and should thus be avoided via appropriation ventilation.
Zinc (Zn), however, although dangerous to breathe, is (for some reason) apparently not one of the dangerous metals listed in the EU’s RoHS-directive, even though Zn can, like other easily-volatilized metals, be dangerous to human health when found in heavy concentrations in the air being breathed.