RoHS (Restriction of Hazardous Substances) is an EU directive (Directive 2011/65/EU and its updates) that restricts ten specific hazardous substances in electrical and electronic equipment placed on the EU market: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBDE), and four phthalates (DEHP, BBP, BDP, DIBP).
For wholesale electronics, RoHS compliance is typically asserted via the Declaration of Conformity that accompanies CE marking. Devices manufactured for the EU market by major OEMs (Apple, Samsung, Xiaomi, etc.) are inherently RoHS-compliant; devices sourced through grey-market or unregistered channels may not be.
Several non-EU markets have implemented RoHS-equivalent regulations: California RoHS (US), China RoHS (separate scheme), Japan J-Moss, South Korea EcoAssurance. A device that meets EU RoHS generally meets the equivalent thresholds elsewhere, but documentation requirements vary by destination.