Copper
Cu·Affects liver, kidneys
An essential nutrient in trace amounts that becomes toxic at the levels that leach from copper plumbing into corrosive water. EPA action level is 1.3 mg/L.
Cu
EPA limit
1.3 mg/L (Action Level)
Most at risk
Infants, people with Wilson's disease, residents of homes with new copper plumbing or corrosive water
Found in
City water · Well water · Industrial areas
AquaOx filters
YesKDF-55 + activated carbon
What it does to you
Health effects
Copper is an essential trace nutrient, but at the concentrations that leach from corroded household plumbing it causes acute gastrointestinal distress: nausea, vomiting, abdominal cramps, and diarrhea. These short-term symptoms are the most common health complaint associated with copper in tap water.
Chronic exposure damages the liver and kidneys. Infants under one year are especially vulnerable because their livers cannot yet regulate copper absorption, and infant formula reconstituted with high-copper tap water has been linked to infant liver injury.
People with Wilson's disease, a genetic disorder of copper metabolism, can suffer severe liver and neurological damage from concentrations that healthy adults tolerate. The EPA set the 1.3 mg/L action level largely to protect these vulnerable groups.
Where it comes from
How it gets into your water
Copper rarely enters water at the treatment plant. It leaches from copper plumbing inside the home, particularly from new copper pipes that have not yet built up a protective interior scale, and from copper-soldered joints. The more corrosive the water, the more copper dissolves.
Low pH, high temperature, and long stagnation time all accelerate copper leaching. The first water drawn from a tap in the morning, after sitting in copper pipes overnight, typically has the highest copper levels of the day.
Industrial sources include copper mining, smelting, and metal-finishing operations, along with copper-based agricultural fungicides and algicides used in reservoirs.
Copper household plumbing
Especially new pipes before scale forms
Copper-soldered joints
Solder seam corrosion releases copper
Mining and smelting discharge
Copper mines and refineries
Reservoir algicides
Copper sulfate added to control algae
Find out for yourself
Is it in your water?
Your utility tests copper under the Lead and Copper Rule and reports the 90th-percentile value from a sample of homes in their Consumer Confidence Report. That number reflects the distribution system, not what's leaving your specific tap.
Because copper leaches from your own plumbing, the only way to know your levels is to test water drawn from your own faucet, ideally first thing in the morning after overnight stagnation. Certified labs run inorganic packages that include copper for $20 to $50.
Blue-green staining on your sinks, tubs, or laundry is the classic visual signal that your water has elevated copper. A metallic, bitter taste is another tell.
The fix
How AquaOx filters it
AquaOx's KDF-55 copper-zinc media reduces copper ions through redox chemistry, converting soluble copper into insoluble forms that get trapped in the filter bed. The activated carbon stages add adsorption capacity for residual copper.
Because AquaOx is whole-house, it protects every fixture, not just the kitchen tap. That matters because copper exposure at the shower head, while not as well studied as ingestion, contributes to the green hair staining that plagues blondes in homes with corrosive copper-plumbed water.