Laboratory Test Directory

Patient Preparation

 

Collect

Royal blue (K₂EDTA or Na₂EDTA).  

Specimen Preparation

Transport 7 mL whole blood in the original collection tube. (Min: 1.5 mL)  

Storage/Transport Temperature

Room temperature. Also acceptable: Refrigerated.  

Unacceptable Conditions

Heparin anticoagulant. Frozen specimens.  

Remarks

Lead requisition form may be required (ARUP form #32990-Barcode; #32991-No Barcode). Notification will be given if required.  

Stability

Mercury is volatile; concentration may reduce after seven or more days of storage. If the specimen is drawn and stored in the appropriate container, the arsenic and lead values do not change with time.  

Information sources for reference intervals and interpretive comments include the "CDC Response to the 2012 Advisory Committee on Childhood Lead Poisoning Prevention Report" and the "Recommendations for Medical Management of Adult Lead Exposure, Environmental Health Perspectives, 2007." Thresholds and time intervals for retesting, medical evaluation, and response vary by state and regulatory body. Contact your State Department of Health and/or applicable regulatory agency for specific guidance on medical management recommendations.

Blood mercury levels predominantly reflect recent exposure and are most useful in the diagnosis of acute poisoning as blood mercury concentrations rise sharply and fall quickly over several days after ingestion. Blood concentrations in unexposed individuals rarely exceed 20 µg/L. The provided reference interval relates to inorganic mercury concentrations. Dietary and non-occupational exposure to organic mercury forms may contribute to an elevated total mercury result. Clinical presentation after toxic exposure to organic mercury may include dysarthria, ataxia and constricted vision fields with mercury blood concentrations from 20 to 50 µg/L.

Potentially toxic ranges for blood arsenic: Greater than or equal to 600 µg/L.

Blood arsenic is for the detection of recent exposure only. Blood arsenic levels in healthy subjects vary considerably with exposure to arsenic in the diet and the environment. A 24-hour urine arsenic is useful for the detection of chronic exposure.