Mercury, 24-Hour Urine

Label Mnemonic: HGU
Epic code: LAB408
Downtime form: Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mailout Laboratory
6240-8 RCP
356-8593
Specimen(s):
24-Hour Urine More information
Specimen Instructions:

Refrigerate during collection in plastic container. Studies indicate that refrigeration of urine alone, during and after collection, preserves specimens adequately, if tested within 14 days of collection.

Patient Prep: Diet, medication, and nutritional supplements may introduce interfering substances. Patients should be encouraged to discontinue nutritional supplements, vitamins, minerals, and non- essential over-the-counter medications (upon the advice of their physician), and avoid shellfish and seafood for 48 to 72 hours. High concentrations of iodine may interfere with elemental testing. Collection of urine specimens from patients receiving iodinated or gadolinium-based contrast media should be avoided for a minimum of 72 hours post-exposure. Collection from patients with impaired kidney function should be avoided for a minimum of 14 days postcontrast media exposure.

Collection Medium:
Urine - 24 hour/timed plastic urine container
Minimum:

Preferred Minimum: 8 mL aliquot from a well-mixed collection from 24 hour collection.

Absolute Minimum: 1 mL aliquot from a well-mixed collection from 24 hour collection.

Refrigerate during collection and submission.

Rejection Criteria:

Urine collected within 72 hours after administration of iodinated or gadolinium-based contrast media. Acid preserved urine. Specimens contaminated with blood or fecal material. Specimens transported in non-trace element free transport tube (with the exception of the original device).

Turn Around Time:

1–5 days upon receipt at reference laboratory

Reference Range:
Components Reference Interval
Creatinine, Urine - per 24h
Age Male (mg/d) Female (mg/d)
3–8 years 140–700 140–700
9–12 years 300–1300 300–1300
13–17 years 500–2300 400–1600
18–50 years 1000–2500 700–1600
51–80 years 800–2100 500–1400
81 years and older 600–2000 400–1300
Mercury, Urine - per 24h Less than or equal to 20.0 microg/d
   
Mercury, Urine - per volume Less than or equal to 5.0 microg/L
Mercury, Urine - ratio to CRT Less than or equal to 20.0 microg/g CRT 
 
Interpretive Data:

Urine mercury concentrations predominantly reflect acute or chronic elemental or inorganic mercury exposure. Urine concentrations in unexposed individuals are typically less than 10 μg/L. 24-hour urine concentrations of 30 to 100 μg/L may be associated with subclinical neuropsychiatric symptoms and tremors. Concentrations greater than 100 μg/L can be associated with overt neuropsychiatric disturbances and tremors. Urine mercury levels may be useful in monitoring chelation therapy.

 

Elevated results may be due to skin or collection-related contamination, including the use of collection containers that are not certified to be trace element-free. If an elevated result is suspected to be due to contamination, confirmation with a second specimen collected in a certified trace element-free container is recommended.

Comments:

Record total volume and collection time interval on transport tube and on test request form.

Stability: Mercury is volatile; concentration may decrease over time.

Methodology:

Quantitative Inductively Coupled Plasma-Mass Spectrometry

CPT Code:
83825
 
See Additional Information:
Collection and Preservation of 24-Hour Urine Specimens
Urine Tests Requiring Preservatives, Refrigeration or Special Containers