- A Good Overview (though slightly back-dated): Quantitative assessment of worldwide contamination of air, water and soil by trace metals 
- A summary of Pollutants from the EPA 
- MCL: 5 ppb
- MCLG: 5 ppb
- Known Carcinogen
- Cadmium Contamination Sites
- Ishihara01 pmid=11376862
- Heavy Metal Limits
- Staessen JA, Lauwerys RR, Ide G, Roels HA, Vyncke G, and Amery A. Renal function and historical environmental cadmium pollution from zinc smelters. Lancet. 1994 Jun 18;343(8912):1523-7.
- Satarug S, Baker JR, Urbenjapol S, Haswell-Elkins M, Reilly PE, Williams DJ, and Moore MR. A global perspective on cadmium pollution and toxicity in non-occupationally exposed population. Toxicol Lett. 2003 Jan 31;137(1-2):65-83.
- MCL: 2 ppb
- MCLG: 2 ppb