Cadmium in Tap Water
Cadmium is a toxic metal that can enter water from the corrosion of galvanized pipes and from industrial discharge, mining, and runoff.
Corrosion of galvanized plumbing; discharge from metal refineries; runoff from waste batteries and paints.
- 1Galvanized pipe corrosion
- 2Industrial / metal-refinery discharge
- 3Battery and paint waste runoff
Most affected: People with reduced kidney function.
A result is read with its context
This contaminant is tracked through federal and state compliance monitoring. Homes with older galvanized plumbing may see higher first-draw results than the system reports. PurityMap does not yet publish a per-system measured value for Cadmium; this page is a reference explainer. To learn what is in your own water, check your utility’s Consumer Confidence Report (CCR) or use a certified home test.
- Above reference
- Evidence exceeds a reference level.
- Detected
- This substance was found in the monitoring record. Being present is not the same as being above a reference level, and this signal does not say which.
- Not detected
- Somebody looked and the laboratory reported nothing above its reporting limit. This is a result, and it is not the same as nobody looking.
- Not monitored
- No sampling for this substance has been reported for this system. Nothing is known either way, and an empty row is not a clean one.
No city results or violations published yet
- MeasurementsPendingNo per-system values
PurityMap does not yet publish a measured value for cadmium.
- ViolationsCheckedNone on the federal record
No city in PurityMap’s record has a cadmium violation in EPA SDWIS since 2016.
- CitiesPendingNo detections on record
No city in PurityMap’s record shows cadmium detected.
This fills in as monitoring data is published. Until then, your utility’s Consumer Confidence Report lists its results, or use a certified home test.
What can carry a cadmium reduction claim
- Reverse osmosis
Semi-permeable membrane separation removing dissolved minerals, heavy metals, and persistent fluorinated chemicals down to 0.0001 microns.
- Ion exchange
Synthetic polyvalent resin beads that exchange unwanted dissolved ionic contaminants for harmless benchmark ions.
- Activated carbon (some configurations)
Highly porous adsorption media targeting chlorine, disinfection byproducts, volatile organic compounds, and organic chemicals.
Boiling does not remove a dissolved chemical compound and can concentrate it. Many pitcher and refrigerator filters carry no verified claim for a compound like this at all.
A finding establishes the need, the need names the capability, the capability requires a verified certification. No product appears before that sequence completes. Filter Finder →
Frequently asked
Answers cite the same records as the page. How PurityMap analyzes water data
Cadmium is a toxic metal that can enter water from the corrosion of galvanized pipes and from industrial discharge, mining, and runoff.
The enforceable federal limit is 0.005 mg/L / 5 µg/L (MCL). The health-based goal (MCLG) is 5 µg/L. PurityMap reads every measurement against its stated benchmark and never sets its own.
Galvanized pipe corrosion, Industrial / metal-refinery discharge, Battery and paint waste runoff.
Long-term exposure above the limit is associated with kidney damage, the organ where cadmium accumulates. The enforceable limit is set to protect against that cumulative effect.
Treatment technologies commonly certified to reduce Cadmium include Reverse osmosis, Ion exchange, Activated carbon (some configurations). Match the exact certified claim to your water before buying. Holding a format is not the same as holding the claim.