Cadmium
Cd·Affects kidneys, bones, lungs
A Group 1 carcinogen and potent kidney toxin that leaches from galvanized pipe corrosion, industrial waste, and old lead-solder impurities. EPA MCL is 0.005 mg/L.
Cd
EPA limit
0.005 mg/L (MCL)
Most at risk
Smokers, residents near smelters or battery plants, people with kidney disease, well users near industrial sites
Found in
City water · Well water · Industrial areas
AquaOx filters
YesKDF-55 + activated carbon
What it does to you
Health effects
Cadmium is classified by the International Agency for Research on Cancer as a Group 1 human carcinogen, with the strongest evidence from inhalation exposure causing lung cancer. Oral exposure through drinking water is associated with kidney, prostate, and pancreatic cancer in long-term studies.
The kidneys are the primary target organ. Cadmium accumulates in renal tissue over decades, with a biological half-life of 10 to 30 years, and chronic exposure causes irreversible tubular damage and proteinuria. Itai-itai disease, the catastrophic bone and kidney syndrome that struck mining-contaminated villages in postwar Japan, was the first documented case of mass cadmium poisoning from water.
Cadmium also weakens bones by interfering with calcium metabolism, leading to osteoporosis and fracture risk after long exposure. It crosses the placenta and is associated with low birth weight.
Where it comes from
How it gets into your water
Cadmium enters water from corrosion of galvanized pipes (zinc galvanization typically contains cadmium impurities), industrial discharge from electroplating, battery manufacturing, pigment production, and plastic stabilizer plants, and from fertilizer runoff in agricultural areas.
Old lead solder used in pre-1986 plumbing often contained cadmium as an impurity, so the same homes flagged for lead risk frequently have a cadmium risk too. Mining tailings and smelter emissions contaminate both surface water and shallow wells in historically industrial regions.
Acidic water dissolves cadmium more readily, so soft, low-pH supplies see higher leaching from any cadmium-containing plumbing.
Galvanized pipe corrosion
Cadmium impurities in zinc coating
Battery and electroplating waste
Nickel-cadmium battery manufacturing
Smelter and mining discharge
Zinc and lead mining tailings
Fertilizer runoff
Phosphate fertilizers contain trace cadmium
Find out for yourself
Is it in your water?
Cadmium is included in the standard inorganic package most certified labs run on well water for $30 to $80. Utilities are required to test for cadmium and report it on their Consumer Confidence Reports.
If your home has galvanized pipes, particularly pre-1960 galvanized steel, request a cadmium test of water drawn from your tap after overnight stagnation. Residents near former smelters, battery plants, or zinc mines should test even on municipal water because of legacy soil and groundwater contamination.
The fix
How AquaOx filters it
AquaOx's KDF-55 copper-zinc media reduces cadmium through redox chemistry, with the alloy converting soluble cadmium ions into insoluble forms that get trapped in the filter bed. The activated carbon stages add adsorption capacity for residual cadmium.
For homes with documented galvanized-pipe leaching or proximity to legacy industrial cadmium contamination, AquaOx recommends pairing the whole-house system with a point-of-use reverse osmosis unit at the kitchen sink. RO filters cadmium to well below the EPA MCL and gives you a dedicated barrier for drinking and cooking water.