Test Id : HGUCR
Mercury/Creatinine Ratio, Random, Urine
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detecting mercury toxicity, a toxic heavy metal, using random urine specimens
Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.
| Test Id | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| HGCU | Mercury/Creatinine Ratio, U | No | Yes |
| CRETR | Creatinine, Random, U | No | Yes |
Method Name
A short description of the method used to perform the test
HGCU: Triple-Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS/MS)
CRETR: Enzymatic Colorimetric Assay
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Hg (Mercury)
Mercury (Hg)
Specimen Type
Describes the specimen type validated for testing
Urine
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Patient Preparation: High concentrations of gadolinium and iodine are known to potentially interfere with most inductively coupled plasma mass spectrometry-based metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 96 hours.
Supplies: Urine Tubes, 10 mL (T068)
Collection Container/Tube: Clean, plastic urine container with no metal cap or glued insert
Submission Container/Tube: Plastic, 10-mL urine tube or clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 3 mL
Collection Instructions:
1. Collect a random urine specimen.
2. See Metals Analysis Specimen Collection and Transport for complete instructions.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
1.5 mL
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 7 days | |
| Frozen | 7 days |
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detecting mercury toxicity, a toxic heavy metal, using random urine specimens
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
The correlation between the levels of mercury (Hg) excretion in the urine and the clinical symptoms is considered poor.
Previous thought indicated urine as a more appropriate marker of inorganic mercury because organic mercury represented only a small fraction of urinary mercury. Based on possible demethylation of methylmercury within the body, urine may represent a mixture of dietary methylmercury and inorganic mercury. Seafood consumption can contribute to urinary mercury levels (up to 30%),(1) which is consistent with the suggestion that due to demethylation processes in the human body, a certain proportion of urinary mercury can originate from dietary consumption of fish/seafood.(2)
Small amounts of mercury are often present in urine, often stemming from environmental exposure or from dental amalgam. The amount of mercury in urine depends upon the form of mercury, the level and duration of mercury exposure, and the elapsed time between exposure and urine sample collection.
For potential mercury vapor exposure: urine mercury levels are unlikely to be useful for assessing potential health effects from short-term, low-level exposures to mercury vapor because such exposures are unlikely to result in mercury urine levels elevated above typical values. High level mercury vapor exposure or long-term, low-level vapor exposures may result in elevated urine mercury levels, which can indicate potential for health effects. Random urine mercury level is adjusted to concentration of creatinine.
Urine mercury concentrations in unexposed individuals are typically less than 10 mcg/L (50 nmol/L) or 2 mcg/g creatinine. Twenty-four-hour urine concentrations of 30 mcg/L to 100 mcg/L (150-499 nmol/L) may be associated with subclinical neuropsychiatric symptoms and tremor, while concentrations greater than 100 mcg/L (499 nmol/L) can be associated with overt neuropsychiatric disturbances and tremors.(4)
Mercury concentrations of greater than 10 mcg/g creatinine may associate with subtle effects on visual memory, attention, manual coordination, mood, increased levels of fatigue and confusion. Higher level of urine mercury is associated with increasing frequent and severe nervous system changes in personality, cognition, and coordination.(3)
Mercury concentrations of 20 mcg/g to 35 mcg/g creatinine may be associated with hand tremors and potential kidney damage.(3)
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
MERCURY/CREATININE:
0-17 years: Not established
> or =18 years: <2 mcg/g creatinine
CREATININE:
> or =18 years: 16-326 mg/dL
Reference values have not been established for patients who are younger than 18 years of age.
Interpretation
Provides information to assist in interpretation of the test results
Daily urine excretion of mercury above 50 mcg/day indicates significant exposure (per World Health Organization standard).
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
To avoid contamination by dust, specimen should be collected away from the site of suspected exposure.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Snoj Tratniid J, Falnoga I, Mazej D, et al. Results of the first national human biomonitoring in Slovenia: Trace elements in men and lactating women, predictors of exposure and reference values Int. J. Hyg Environ Health. 2019;222(3):563-582
2. Sherman LS, Blum JD, Franzblau A, Basu N. New insights into biomarkers of human mercury exposure using naturally occurring mercury stable isotopes. Environ Sci and Tech. 2013;47(7):3403-3409
3. McKelvey W, Alex B, Chernov C, et al. Tracking Declines in Mercury Exposure in the New York City Adult Population, 2004-2014. J Urban Health. 2018;95(6):813-825
4. Agency for Toxic Substances and Disease Registry. Atsdr - addendum to the toxicological profile: Mercury. 2022.
5. Lee R, Middleton D, Caldwell K, et al. A review of events that expose children to elemental mercury in the United States. Environ Health Perspect. 2009;117(6):871-878
6. Bjorkman L, Lundekvam BF, Laegreid T, et al. Mercury in human brain, blood, muscle and toenails in relation to exposure: an autopsy study. Environ Health. 2007 11;6:30
7. Bernhoft RA. Mercury toxicity and treatment: a review of the literature. J Environ Public Health. 2012;2012:460508. doi:10.1155/2012/460508
8. Strathmann FG, Blum LM: Toxic elements. In: Rifai N, Chiu RWK, Young I, Burnham CD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:chap 44
Method Description
Describes how the test is performed and provides a method-specific reference
Mercury:
The metal of interest is analyzed by triple-quadrupole inductively coupled plasma mass spectrometry.(Unpublished Mayo method)
Creatinine:
The enzymatic method is based on the determination of sarcosine from creatinine with the aid of creatininase, creatinase, and sarcosine oxidase. The liberated hydrogen peroxide is measured via a modified Trinder reaction using a colorimetric indicator. Optimization of the buffer system and the colorimetric indicator enables the creatinine concentration to be quantified both precisely and specifically.(Package insert: Creatinine plus ver 2. Roche Diagnostics; V15.0, 03/2019)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Friday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
83825
82570
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| HGUCR | Mercury/Creat Ratio, Random,U | 13465-0 |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| CRETR | Creatinine, Random, U | 2161-8 |
| 608903 | Mercury/Creatinine Ratio, U | 13465-0 |