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Official Description

Mercury, quantitative

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 83825 refers to a quantitative test for mercury levels in various biological samples, including blood, urine, hair, fingernails, and other body tissues. Mercury is classified as a heavy metal, and exposure to high levels can be toxic to the human body. Individuals may encounter mercury through several routes, such as consuming certain types of fish that contain mercury, exposure to dental amalgams used in fillings, the presence of thimerosal as a preservative in some vaccines, or through occupational exposure in certain work environments. The testing process involves obtaining a blood sample, which is performed through a separately reportable venipuncture. The analysis of whole blood is conducted using quantitative atomic absorption or quantitative inductively coupled plasma-mass spectrometry techniques. Additionally, a random voided or 24-hour urine specimen can be collected and tested using quantitative inductively coupled plasma-mass spectrometry. For scalp hair, fingernail clippings, and other body tissue samples, the testing is performed using inductively coupled plasma/mass spectrometry methods. This comprehensive approach allows for accurate measurement of mercury levels, which is essential for assessing potential toxicity and guiding further medical evaluation or intervention.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The quantitative mercury test (CPT® Code 83825) is indicated for the assessment of mercury exposure and toxicity. The following conditions and situations may warrant this testing:

  • Occupational Exposure Individuals who work in environments where mercury is present, such as certain manufacturing or laboratory settings, may require testing to monitor mercury levels in their bodies.
  • Consumption of Contaminated Fish Patients who frequently consume fish known to have high mercury levels may be tested to evaluate their mercury exposure.
  • Symptoms of Mercury Toxicity Individuals presenting with symptoms suggestive of mercury poisoning, such as neurological issues, gastrointestinal disturbances, or respiratory problems, may be tested to confirm or rule out mercury toxicity.
  • Dental Amalgam Concerns Patients with dental amalgams containing mercury may seek testing to assess their mercury levels, especially if they experience health issues that could be related to mercury exposure.
  • Thimerosal Exposure Individuals who have received vaccines containing thimerosal may be tested to evaluate potential mercury accumulation in the body.

2. Procedure

The procedure for conducting the quantitative mercury test involves several key steps, each critical for ensuring accurate results:

  • Step 1: Sample Collection A blood sample is obtained through a procedure known as venipuncture, which is separately reportable. This involves inserting a needle into a vein to draw blood, ensuring that the sample is collected in a manner that minimizes contamination and preserves its integrity for testing.
  • Step 2: Whole Blood Testing The collected whole blood sample is then analyzed using quantitative atomic absorption or quantitative inductively coupled plasma-mass spectrometry. These advanced techniques allow for precise measurement of mercury levels in the blood, providing essential data for evaluating exposure.
  • Step 3: Urine Specimen Collection In addition to blood testing, a random voided or 24-hour urine specimen is collected from the patient. This urine sample is also subjected to quantitative inductively coupled plasma-mass spectrometry, which helps in assessing the excretion of mercury and provides further insight into the body’s mercury burden.
  • Step 4: Testing of Other Samples For comprehensive evaluation, scalp hair, fingernail clippings, and other body tissue samples may be collected. These samples are tested using inductively coupled plasma/mass spectrometry, which is effective in detecting mercury levels in various biological matrices, thus enhancing the overall assessment of mercury exposure.

3. Post-Procedure

After the quantitative mercury test is completed, patients may be advised on several post-procedure considerations. It is important to monitor for any symptoms of mercury toxicity, especially if elevated levels are detected. Patients should also be informed about the potential need for follow-up testing or further evaluation based on the results. Additionally, healthcare providers may discuss dietary modifications, particularly regarding fish consumption, and occupational safety measures to reduce future exposure to mercury. The results of the test will guide clinical decisions and any necessary interventions to address mercury exposure and its potential health effects.

Short Descr ASSAY OF MERCURY
Medium Descr ASSAY OF MERCURY QUANTITATIVE
Long Descr Mercury, quantitative
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 2
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GA Waiver of liability statement issued as required by payer policy, individual case
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
GZ Item or service expected to be denied as not reasonable and necessary
GW Service not related to the hospice patient's terminal condition
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
Date
Action
Notes
2013-01-01 Changed Medium Descriptor changed.
Pre-1990 Added Code added.
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Description
Code
Description
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