Archives of Toxicology

, Volume 81, Issue 11, pp 759–767 | Cite as

Mercuric dichloride induces DNA damage in human salivary gland tissue cells and lymphocytes

  • Katharina Schmid
  • Andrea Sassen
  • Rainer Staudenmaier
  • Susanne Kroemer
  • Franz-Xaver Reichl
  • Ulrich Harréus
  • Rudolf Hagen
  • Norbert Kleinsasser
Inorganic Compounds


Amalgam is still one of the most frequently used dental filling materials. However, the possible adverse effects especially that of the mercuric component have led to continued controversy. Considering that mercury may be released from amalgam fillings into the oral cavity and also reach the circulating blood after absorption and resorption, it eventually may contribute to tumorigenesis in a variety of target cells. The present investigation focuses on genotoxic effects below a cytotoxic dose level of mercuric dichloride (HgCl2) in human samples of salivary glands and lymphocytes to elucidate a possible role in tumor initiation. DNA migration due to single strand breaks, alkali labile sites and incomplete excision repair was quantified with the aid of the single cell microgel electrophoresis (Comet) assay. The concepts of Olive Tail Moment, percentage of DNA in the Tail and Tail Length were used as measures of DNA damage. To control for cytotoxic effects, the trypan blue exclusion test was applied. Human samples of the parotid salivary gland and lymphocytes of ten donors were exposed to HgCl2 concentrations from 1 to 50 μM. N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) and dimethyl sulfoxide (DMSO) served as controls. Increasing dose-dependent DNA migration could be demonstrated after exposure to HgCl2 in cells of the salivary glands and lymphocytes. In both cell types a significant increase in DNA migration could be shown starting from HgCl2 concentrations of 5 μM in comparison to the negative control. The viability of the cell systems was not affected except at the highest concentration (50 μM) tested. These data indicate genotoxic effects of mercuric dichloride in human salivary glands and lymphocytes at concentrations not leading to cytotoxic effects or cell death. Consequently, a contributory role in oral salivary gland tumor initiation warrants further investigation.


Mercuric dichloride Genotoxicity Salivary glands Human study Comet assay 


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Katharina Schmid
    • 1
  • Andrea Sassen
    • 2
  • Rainer Staudenmaier
    • 3
  • Susanne Kroemer
    • 1
  • Franz-Xaver Reichl
    • 4
  • Ulrich Harréus
    • 5
  • Rudolf Hagen
    • 6
  • Norbert Kleinsasser
    • 6
  1. 1.University of RegensburgRegensburgGermany 
  2. 2.Department of PathologyUniversity of RegensburgRegensburgGermany
  3. 3.Department of Otorhinolaryngology, Head and Neck SurgeryTechnical University of MunichMunichGermany
  4. 4.Institute of Pharmacology and ToxicologyUniversity of MunichMunichGermany
  5. 5.Department of Otorhinolaryngology, Head and Neck SurgeryUniversity of MunichMunichGermany
  6. 6.Department of Otorhinolaryngology, Head and Neck SurgeryUniversity of WuerzburgWuerzburgGermany

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