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Epic Code LAB1230421 Lead, 24 Hour, Urine

Additional Codes

Mayo Code: PBU

Epic Code: LAB 1230421

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Useful For

Detecting clinically significant lead exposure in 24-hour specimens

 

This test is not a substitute for blood lead screening.

Specimen Type

Urine
Laboratory Test Directory Note:

Refrigeration during and after urine collection is the preferred means of urine preservation.


Ordering Guidance


The Centers for Disease Control and Prevention recommends venous blood collection for lead testing; see PBDV / Lead, Venous, with Demographics, Blood



Necessary Information


24-Hour volume (in milliliters) is required.



Specimen Required


Patient Preparation: High concentrations of gadolinium and iodine are known to interfere with most 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 a clean, plastic aliquot container with no metal cap or glued insert

Specimen Volume: 3 mL

Collection Instructions:

1. Collect urine for 24 hours.

2. Refrigerate specimen within 4 hours of completion of 24-hour collection.

3. See Metals Analysis Specimen Collection and Transport for complete instructions.

Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.


Specimen Minimum Volume

1.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Ambient  28 days
  Frozen  28 days

Urine Preservative Collection Options

Note: The addition of preservative or application of temperature controls must occur within 4 hours of completion of the collection.

Ambient (no additive)

OK

Refrigerate (no additive)

Preferred

Frozen (no additive)

OK

50% Acetic Acid

OK

Boric Acid

No

Diazolidinyl Urea

No

6M Hydrochloric Acid

OK

6M Nitric Acid

OK

Sodium Carbonate

No

Thymol

No

Toluene

No

Reject Due To

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Day(s) Performed

Monday through Friday

Reference Values

0-17 years: Not established

≥18 years: <2 mcg/24 h

Clinical Information

Increased urine lead excretion rate indicates significant lead exposure. Measurement of urine lead excretion rate before and after chelation therapy has been used as an indicator of lead exposure. However, the American College of Medical Toxicology (ACMT 2010) position statement on post-chelator challenge urinary metal testing states that "post-challenge urinary metal testing has not been scientifically validated, has no demonstrated benefit, and may be harmful when applied in the assessment and treatment of patients in whom there is concern for metal poisoning."

 

For more information see PBDV/ Lead, Venous, with Demographics, Blood.

Cautions

No significant cautionary statements.

Interpretation

Measurements of urinary lead (Pb) levels have been used to assess lead exposure. However, like lead blood, urinary lead excretion mainly reflects recent exposure and thus shares many of the same limitations for assessing lead body burden or long-term exposure.(1,2)

 

Urinary lead concentration increases exponentially with blood lead and can exhibit relatively high intra-individual variability, even at similar blood lead concentrations.(3,4)

Reporting Name

Lead, 24 Hr, U

Method Name

Triple-Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS/MS)

Method Description

The metal of interest is analyzed by inductively coupled plasma mass spectrometry.(Unpublished Mayo method).

CPT Code Information

83655

LOINC Code Information

Test ID Test Order Name Order LOINC Value
PBU Lead, 24 Hr, U 5677-0

 

Result ID Test Result Name Result LOINC Value
31085 Lead, 24 Hr, U 5677-0
TM83 Collection Duration 13362-9
VL84 Urine Volume 3167-4

Report Available

1 to 3 days

Test Classification

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.

Clinical Reference

1. Sakai T. Biomarkers of lead exposure. Ind Health. 2000;38(2):127-142

2. Skerfving S. Biological monitoring of exposure to inorganic lead. In: Clarkson TW, Friberg L, Nordberg GF, Sager PR, eds. Biological Monitoring of Toxic Metals. Rochester Series on Environmental Toxicity. Springer; 1988:169-197

3. Gulson BL, Jameson CW, Mahaffey KR, et al. Relationships of lead in breast milk to lead in blood, urine, and diet of the infant and mother. Environ Health Perspect. 1998;106(10):667-674

4. Skerfving S, Ahlgren L, Christoffersson JO, et al. Metabolism of inorganic lead in man. Nutr Res. 1985;Suppl 1:601-607

5. Kosnett MJ, Wedeen RP, Rotherberg SJ, et al. Recommendations for medical management of adult lead exposure. Environ Health Perspect. 2007;115(3):463-471

6. de Burbane C, Buchet JP, Leroyer A, et al. Renal and neurologic effects of cadmium, lead, mercury, and arsenic in children: evidence of early effects and multiple interactions at environmental exposure levels. Environ Health Perspect. 2006;114(4):584-590

7. Pascal DC, Ting BG, Morrow JC, et al. Trace metals in urine of United States residents: reference range concentrations. Environ Res. 1998;76(1):53-59

8. Hauptman M, Bruccoleri R, Woolf AD. An update on childhood lead poisoning. Clin Pediatr Emerg Med. 2017;18(3):181-192. doi:10.1016/j.cpem.2017.07.010

9. 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