Overview#
Cadmium is a soft heavy metal that is carcinogenic and toxic to the kidneys and bones. It carries the tightest limit of any RoHS-restricted metal, ten times stricter than lead or mercury.
Where it's restricted#
RoHS sets the strictest threshold of the regulated metals, 0.01 percent by weight per homogeneous material. Cadmium is also restricted in vehicles under ELV.
Outside RoHS, REACH Annex XVII restricts cadmium in plastics, in jewellery and in brazing fillers. Cadmium in batteries is addressed separately under the Battery Regulation.
Typical uses#
Cadmium has been used as a colour pigment, as a plating to resist corrosion, in nickel-cadmium rechargeable batteries, and in some electrical contacts. Most of these uses are now limited or replaced.
Cadmium's 0.01 percent threshold is ten times lower than the 0.1 percent applied to most other RoHS substances, so trace contamination matters more here.