Copper

Note: this site is for informational purposes only. To view test results or book a test, use the NHS app in England or contact your GP.

A copper test measures the amount of copper in a blood sample, and sometimes in urine or liver tissue, to assess copper levels in the body. It is used to help diagnose and monitor disorders of copper metabolism, particularly Wilson disease and conditions associated with copper deficiency or excess.

Also known as 
Cu; 24-hour urine copper; Total copper; Non-caeruloplasmin-bound copper; Free copper; Hepatic copper 
Formal name 
Copper (24-hour urine, total and free blood, and hepatic) 

Why get tested?

To measure the amount of copper in the blood, urine, or liver; to help diagnose and monitor Wilson disease; to identify copper deficiencies and excesses.

When to get tested?

When you have jaundice, fatigue, abdominal pain, behavioural changes, tremor, or other symptoms that your doctor thinks may be due to Wilson disease or, rarely, to copper deficiency or excess; at intervals when you are being treated with copper or for a copper-related condition.

Sample required?

A blood sample taken from a vein in your arm and/​or a 24-hour urine sample; sometimes a liver biopsy sample.

Test preparation needed?

No test preparation is needed.

What is being tested?

This test measures the amount of copper in the blood, urine, or liver (hepatic). Copper is an essential mineral that the body incorporates into enzymes. These enzymes play a role in the regulation of iron metabolism, formation of connective tissue, energy production at the cellular level, the creation of melanin, and the function of the nervous system and brain.

Copper is found in many foods including nuts, chocolate, mushrooms, shellfish, whole grains, dried fruits, and liver. Drinking water may acquire copper as it flows through copper pipes, and food may acquire it when people cook or serve food in copper dishes. Normally, the body absorbs copper from the intestines, makes it non-toxic by binding it to a protein, and transports it to the liver. The liver stores some of the copper and binds most of the rest to a protein called apocaeruloplasmin that, when copper is attached, becomes the enzyme caeruloplasmin. About 95% of the copper in the blood is bound to caeruloplasmin. The liver excretes excess copper into the bile and it is removed from the body in the stool. Some copper is also excreted in the urine.

Both excesses and deficiencies of copper are rare. Wilson disease, an inherited disorder, can lead to excess storage of copper in the liver, brain, and other organs. This can cause tissue damage and signs and symptoms such as:

  • anaemia
  • nausea
  • abdominal pain
  • jaundice
  • fatigue
  • behavioural changes
  • tremor
  • difficulty walking and/​or swallowing
  • dystonia

If the kidneys are involved, then urine production may be decreased or absent. Some of these symptoms may also be seen with copper poisoning that is due to acute or chronic environmental exposure to copper or due to conditions such as liver disease or obstructions that prevent or inhibit copper metabolism and excretion.

Copper deficiencies may occasionally occur in patients who have conditions associated with severe malabsorption, such as cystic fibrosis and coeliac disease, and in infants exclusively fed cow-milk formulas. Findings may include reduced white blood cells, osteoporosis, and microcytic anaemia. A rare X‑linked genetic condition called Menkes kinky hair syndrome leads to copper deficiencies in the brain and liver of affected infants. The disease, which affects primarily males, is associated with seizures, delayed development, abnormal artery development in the brain, and unusual grey brittle kinky hair.

Common questions