Sign in →

Test ID: ASNA Arsenic, Nails

Reporting Name

Arsenic, Nails

Useful For

Detection of nonacute arsenic exposure

Clinical Information

Arsenic circulating in the blood will bind to protein by formation of a covalent complex with sulfhydryl groups of the amino acid cysteine. Keratin, the major structural protein in hair and nails, contains many cysteine residues and, therefore, is one of the major sites for accumulation of arsenic. Since arsenic has a high affinity for keratin, the concentration of arsenic in nails is higher than in other tissues.

 

Several weeks after exposure, transverse white striae, called Mees' lines, may appear in the fingernails.

Interpretation

Nails grow at a rate of approximately 0.1 inch/month. Nail keratin synthesized today will grow to the distal end in approximately 6 months. Thus, a nail specimen collected at the distal end represents exposure of 6 months ago.

 

Nail arsenic above 1.0 mcg/g dry weight may indicate excessive exposure. It is normal for some arsenic to be present in nails, as everybody is exposed to trace amounts of arsenic from the normal diet.

 

The highest hair or nail arsenic observed at Mayo Clinic was 210 mcg/g dry weight in a case of chronic exposure that was the cause of death.

Analytic Time

2 days

Day(s) and Time(s) Performed

Tuesday; 3 p.m.

Clinical Reference

Hindmarsh JT, McCurdy RF: Clinical and environmental aspects of arsenic toxicity. Crit Rev Clin Lab Sci 1986;23:315-347

Method Name

Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

Specimen Type

Nail


Specimen Required


Supplies: Hair and Nails Collection Kit (T565)

Specimen Volume: 0.2 g

Collection Instructions:

1. Prepare and transport specimen per the instructions in the kit or see Collecting Hair and Nails for Metals Testing in Special Instructions.

2. Clippings should be taken from all 10 fingernails or toenails.

Additional Information: If known, indicate source of nails (fingernails or toenails).


Specimen Minimum Volume

0.05 g

Specimen Stability Information

Specimen Type Temperature Time Special Container
Nail Ambient (preferred)
  Frozen 
  Refrigerated 

Reference Values

0-15 years: not established

≥16 years: <1.0 mcg/g of nails

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

82175

LOINC Code Information

Test ID Test Order Name Order LOINC Value
ASNA Arsenic, Nails 8157-0

 

Result ID Test Result Name Result LOINC Value
2535 Arsenic, Nails 8157-0
ASNSC Specimen Source 31208-2
Mayo Clinic Laboratories | Neurology Catalog Additional Information:

mml-Behavioral, mml-Neuromuscular