Skip to content

Mercury, Total, Urine — Creatinine Ratio

Published: August 9, 2026Updated: August 16, 2026

A urine test that measures mercury relative to creatinine, helping account for differences in urine concentration.

Quick summary

["An elevated result may indicate exposure to mercury, although recent fish or shellfish consumption can also raise urine mercury levels."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
56653-9
Short code
Mercury/Creat Ur-Rto
Synonyms
Mercury/Creat Ur-Rto
Category
kidney
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

This test measures the amount of mercury in urine and compares it with the amount of creatinine in the same sample. Creatinine is used to help adjust for how concentrated or dilute the urine is.

Why might I need this test?

A clinician may order this test to assess possible mercury exposure, particularly after workplace exposure, accidental ingestion, or contact with contaminated materials. It can also help monitor people who are being evaluated or treated for suspected toxicity.

How is the test performed?

You provide a urine sample according to your clinician's or laboratory's instructions. The laboratory measures mercury and creatinine and calculates the mercury-to-creatinine ratio.

How do I prepare for the test?

Follow all collection instructions and tell your clinician about any recent fish or shellfish consumption, supplements, or possible mercury exposure. Your clinician may advise dietary changes before collection because some seafood can temporarily increase urine mercury.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

An elevated urine mercury-to-creatinine ratio may suggest recent or ongoing mercury exposure, but it does not by itself determine the source or severity of exposure. Results can also be influenced by eating fish or shellfish shortly before the test. Interpretation should consider symptoms, exposure history, and other laboratory findings.

Short name

Urine mercury-to-creatinine ratio

Frequently asked questions

Does this test show whether I have mercury poisoning?
Not by itself. The result is interpreted with your symptoms, exposure history, and other tests to assess whether mercury exposure could be affecting your health.
Why is the result divided by creatinine?
Urine can be more or less concentrated depending on how much water you drink. Using creatinine helps reduce the effect of urine concentration on the reported ratio.
Can eating fish affect my result?
Yes. Fish and shellfish may contain mercury and can raise urine levels, especially when eaten shortly before collection. Tell your clinician about recent seafood consumption.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy