Detection of nonacute arsenic, mercury, and lead exposure using hair specimens
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
ASHA | Arsenic, Hair | Yes | Yes |
PBHA | Lead, Hair | Yes | Yes |
HGHAR | Mercury, Hair | Yes | Yes |
Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)
Arsenic (As)
As (Arsenic)
Hg (Mercury)
Lead (Pb)
Mercury (Hg)
Pb (Lead)
Hair
Indicate source of hair (axillary, head, or pubic), if known
Question ID | Description | Answers |
---|---|---|
ASHSC | Specimen Source | |
HGHSC | Specimen Source | |
PBHSC | Specimen Source |
Supplies: Hair and Nails Collection Kit (T565)
Specimen Volume: 0.2 g
Collection Instructions: Prepare and transport specimen per the instructions in kit or see Collecting Hair and Nails for Metals Testing.
0.05 g
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Hair | Ambient (preferred) | ||
Frozen | |||
Refrigerated |
Detection of nonacute arsenic, mercury, and lead exposure using hair specimens
ARSENIC
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 hair is higher than in other tissues.
Arsenic binds to keratin at the time of exposure, "trapping" the arsenic in hair. Therefore, hair analysis for arsenic is not only used to document that an exposure occurred, but when it occurred. Hair collected from the nape of the neck can be used to document recent exposure. Axillary or pubic hairs are used to document long-term (6 months-1 year) exposure.
MERCURY
Once absorbed and circulating, mercury becomes bound to numerous proteins, including keratin. The concentration of mercury in hair correlates with the severity of clinical symptoms. If the hair can be segregated by length, such an exercise can be useful in identifying the time of exposure.
LEAD
Hair analysis for lead can be used to corroborate blood analysis or to document past lead exposure. If the hair is collected and segmented in a time sequence (based on length from root), the approximate time of exposure can be assessed.
ARSENIC
0-15 years: Not established
> or =16 years: <1.0 mcg/g of hair
LEAD
<4.0 mcg/g of hair
Reference values apply to all ages.
MERCURY
0-15 years: Not established
> or =16 years:<1.0 mcg/g of hair
Hair grows at a rate of approximately 0.5 inch/month. Hair keratin synthesized today will protrude through the skin in approximately 1 week. Thus, a hair specimen collected at the skin level represents exposure of 1 week ago, 1 inch distally from the skin represents exposure 2 months ago, etc.
ARSENIC
Hair arsenic levels above 1.00 mcg/g dry weight may indicate excessive exposure. It is normal for some arsenic to be present in hair, as everybody is exposed to trace amounts of arsenic from the normal diet.
The highest hair arsenic observed at Mayo Clinic was 210 mcg/g dry weight in a case of chronic exposure, which was the cause of death.
MERCURY
Normally, hair contains less than 1 mcg/g of mercury; any amount more than this indicates that exposure to more than normal amounts of mercury may have occurred.
LEAD
Normal hair lead content is below 4.0 mcg/g. While hair lead content above 10.0 mcg/g may indicate significant lead exposure, hair is also subject to potential external contamination with environmental lead and contaminants in artificial hair treatments (eg, dyeing, bleaching, or permanents). Ultimately, the hair lead content needs to be interpreted in addition to the overall clinical scenario including symptoms, physical findings, and other diagnostic results when determining further actions.
No significant cautionary statements
1. Sthiannopkao S, Kim K-W, Cho KH, et al. Arsenic levels in human hair, Kandal Province, Cambodia: The influences of groundwater arsenic, consumption period, age and gender. Applied Geochemistry. 2010;25:81-90
2. Pearse DC, Dowling K, Gerson, AR, et al. Arsenic microdistribution and speciation in toenail clippings of children living in a historic gold mining area. Sci Total Environ. 2010;408:2590-2599
3. Marques RC, Dorea JG, Bastos WR, Malm O. Changes in children hair-Hg concentrations during the first 5 years: maternal, environmental and iatrogenic modifying factors. Reg Toxicol Pharmacol. 2007;49:17-24
4. Canuel R, de Grosbois SB, Atikesse L, et al. New evidence on variations of human body burden of methylmercury from fish consumption. Environ Health Perspect. 2006;114:302-306
5. Barbosa F, Tanus-Santos J, Gerlach R, Parsons P. A Critical review of biomarkers used for monitoring human exposure to lead: advantages, limitations, and future needs. Environ Health Perspect. 2005;113:1669-1674
6. DiPietro ES, Phillips DL, Paschal DC, Neese JW. Determination of trace elements in human hair. Biol Trace Elem Res. 1989;22:83-100
7. Strathmann FG, Blum LM. Toxic elements. In: Nader R, Horwath AR, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. Elsevier; 2023:chap 44
The metals of interest are analyzed by inductively coupled plasma mass spectrometry.(Unpublished Mayo method)
Tuesday
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.
82175-ASHA
83655-PBHA
83825-HGHAR
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
HMHA | Heavy Metals, Hair | 34667-6 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
31896 | Arsenic, Hair | 5584-8 |
ASHSC | Specimen Source | 31208-2 |
31900 | Mercury, Hair | 5686-1 |
HGHSC | Specimen Source | 31208-2 |
31898 | Lead, Hair | 5673-9 |
PBHSC | Specimen Source | 31208-2 |