What is cadmium? Metal uses, toxicity and EU limits explained
Cadmium (Cd, atomic number 48) is a soft, silver-white toxic metal used in NiCd batteries, pigments and plating. See its hazards and EU and UK limits.
What is cadmium?
Cadmium is a soft, silver-white metal with the symbol Cd and atomic number 48, used in nickel-cadmium batteries, pigments, plating and plastic stabilisers. It is a human carcinogen that can damage the kidneys and bones.
Cadmium element basics
The IARC monograph on cadmium gives the CAS number 7440-43-9. The EC number is 231-152-8 (ECHA substance page).
IARC, quoting 2007 US Geological Survey figures, put nickel-cadmium batteries at 83% of use, pigments at 8%, coatings and plating at 7%, plastic stabilisers at 1.2%, and other uses (alloys, semiconductors and CdTe/CdS solar cells) at 0.8%. Those shares are not today's market.
Why cadmium is restricted
The WHO lists cadmium as toxic to the kidney, the skeleton, and the respiratory system. IARC puts cadmium and its compounds in Group 1, carcinogenic to humans. The EU classification also covers acute inhalation toxicity, suspected mutagen and reproductive effects, and aquatic toxicity.
Cadmium has been on the REACH Candidate List since 20 June 2013, for carcinogenicity and for organ toxicity after repeated exposure.
For food, EFSA set a tolerable weekly intake of 2.5 µg per kg of body weight in 2009 and kept it in 2011. Food is the main exposure for non-smokers (EFSA metals topic).
Is cadmium plating banned in the EU?
Not a blanket ban. REACH Annex XVII entry 23 defines cadmium plating as any metallic cadmium coating on a metal surface. It bans that plating on equipment and machinery for food production, agriculture, cooling and freezing, printing and book-binding, household goods, furniture, sanitary ware, central heating and air conditioning, paper and board, textiles and clothing, industrial handling equipment, road and agricultural vehicles, rolling stock and vessels. Placing those plated articles on the market is banned too.
Aeronautical, aerospace, mining, offshore and nuclear uses stay exempt where the application needs high safety standards. So do safety devices in road and agricultural vehicles, rolling stock and vessels, and electrical contacts where reliability requires cadmium.
But other laws also apply. The RoHS Directive caps cadmium at 0.01% by weight of homogeneous material in electrical and electronic equipment. Its exemptions for cadmium in electrical contacts, entries 8(b) and 8(b)-I, have expired. A REACH contacts exemption does not clear a RoHS product.
Main EU cadmium limits in products
Note the different weight bases: plastic, paint, metal or whole battery.
| Product | Limit | Source |
|---|---|---|
| Listed plastics, including PVC, PUR and LDPE | 0.01% by weight of the plastic | REACH entry 23 |
| Paints | 0.01% by weight of the paint (0.1% if zinc exceeds 10%). Painted articles: 0.1% of the paint | REACH entry 23 |
| Jewellery, hair accessories, watches | 0.01% by weight of the metal | REACH entry 23 |
| Portable batteries | 0.002% by weight, no exemptions | Batteries Regulation |
| Packaging | 100 mg/kg for lead, cadmium, mercury and hexavalent chromium combined | PPWR Art. 5(4) |
| EU phosphate fertilisers with at least 5% P2O5 | 60 mg Cd/kg P2O5 | Fertilising Products Regulation |
REACH entry 23 allows up to 0.1% cadmium in recovered PVC for specified rigid building uses, if the product is marked "Contains recovered PVC". Plastic articles placed on the market before 10 December 2011 are exempt from that plastics limit. Jewellery placed on the market before that date is exempt, as is jewellery already more than 50 years old on that date. Emergency, alarm and medical exemptions from the old batteries directive are gone (Batteries Regulation). The 60 mg/kg phosphate cap was due for review in July 2026, so check the amending act before you rely on it.
Toy migration limits are 1.3 mg/kg for dry, brittle, powder-like or pliable material, 0.3 mg/kg for liquid or sticky material, and 17 mg/kg for scraped-off material (Toy Safety Directive).
Cadmium in food and chocolate
Regulation (EU) 2023/915 sets cadmium maximum levels by total dry cocoa solids:
- milk chocolate under 30%: 0.10 mg/kg
- chocolate under 50%, and milk chocolate at 30% or more: 0.30 mg/kg
- chocolate at 50% or more: 0.80 mg/kg
- cocoa powder for the final consumer, including use in sweetened cocoa powder or powdered chocolate (drinking chocolate): 0.60 mg/kg
There's no separate EU band above 70%. The same regulation sets 0.10 mg/kg for cereals, 0.15 mg/kg for rice and 0.040 mg/kg for baby food.
Belgium and the UK
Belgium's FPS Health summarises the EU product rules on its heavy metals page. In Great Britain, UK REACH keeps entry 23 with the same limits as the EU text, as retained at 31 December 2020. England and Wales apply assimilated Regulation 1881/2006 for food (gov.uk), and the chocolate figures match. Northern Ireland follows 2023/915.
RegAffairs AI has a cited answer on cadmium plating and chocolate limits.