Clinical use: Mercury testing can be tested when mercury toxicity is suspected.
Background:

Mercury (Hg) is essentially nontoxic in its elemental form. If Hg(0) is chemically modified to the ionized, inorganic species, Hg(+2), it becomes toxic. Further bioconversion to an alkyl Hg, such as methyl Hg (CH[3]Hg[+]), yields a species of mercury that is highly selective for lipid-rich tissue such as neurons and is very toxic. Mercury can be chemically converted from the elemental state to the ionized state. In industry, this is frequently done by exposing Hg(0) to strong oxidizing agents such as chlorine.

Mercury expresses its toxicity in 3 ways:

  • Hg(+2) is readily absorbed and reacts with sulfhydryl groups of protein, causing a change in the tertiary structure of the protein-a stereoisomeric change-with subsequent loss of the unique activity associated with that protein. Because Hg(+2) becomes concentrated in the kidney during the regular clearance processes, this target organ experiences the greatest toxicity.
  • With the tertiary change noted previously, some proteins become immunogenic, eliciting a proliferation of T lymphocytes that generate immunoglobulins to bind the new antigen; collagen tissues are particularly sensitive to this.
  • Alkyl Hg species, such as CH[3]Hg[+], are lipophilic and avidly bind to lipid-rich tissues such as neurons. Myelin is particularly susceptible to disruption by this mechanism.
Reference ranges: Blood: 0 – 16 nmol/L
Urine: 0 – 2 umol/mol Creatinine
Associated diseases:
Patient preparation:
Specimen requirements: Whole Blood: Sodium Heparin Trace Element Tube
Urine: Random urine sample in a plain container
Turnaround time: 2 weeks
Additional information:
Referred test: Referred test
Location: University of Wales Hospital, Cardiff