Validation of methodology for determination of the mercury methylation potential in sediments using radiotracers


Experiments to determine the mercury methylation potential were performed on sediments from two locations on the river Idrijca (Slovenia), differing in ambient mercury concentrations. The tracer used was the radioactive isotope 197Hg. The benefit of using this tracer is its high specific activity, which enables spikes as low as 0.02 ng Hg2+ g−1 of sample to be used. It was therefore possible to compare the efficiency of the methylation potential experiments over a range of spike concentrations from picogram to microgram levels. The first part of the work aimed to validate the experimental blanks and the second part consisted of several series of incubation experiments on two different river sediments using a range of tracer additions. The results showed high variability in the obtained methylation potentials. Increasing Hg2+ additions gave a decrease in the percentage of the tracer methylated during incubation; in absolute terms, the spikes that spanned four orders of magnitude (0.019–190 pg g−1 of sediment slurry) resulted in MeHg formation between 0.01 and 0.1 ng MeHg g−1 in Podroteja and Kozarska Grapa. Higher spikes resulted in slightly elevated MeHg production (up to a maximum of 0.27 ng g−1). The values of methylation potential were similar in both sediments. The results imply that the experimental determination of mercury methylation potential strongly depends on the experimental setup itself and the amount of tracer added to the system under study. It is therefore recommended to use different concentrations of tracer and perform the experiments in several replicates. The amount of mercury available for methylation in nature is usually very small. Therefore, adding very low amounts of tracer in the methylation potential studies probably gives results that have a higher environmental relevance. It is also suggested to express the results obtained in absolute amounts of MeHg produced and not just as the percentage of the added tracer.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9


  1. 1.

    UNEP (2002) Global mercury assessment. United Nations Environment Programme, Geneva

  2. 2.

    Horvat M, Kontić B, Kotnik J, Ogrinc N, Jereb V, Logar M, Faganeli J, Rajar R, Širca A, Petkovšek G, Žagar D, Dizdarevič T (2003) Crit Rrev Anal Chem 33:291–296

    Article  CAS  Google Scholar 

  3. 3.

    Munthe J, Bodaly D, Branfireun B, Driscoll C, Gilmour CC, Harris R, Horvat M, Lucotte M, Malm O (2007) Ambio 36(1):33–44

    Article  Google Scholar 

  4. 4.

    Horvat M, Jereb V, Fajon V, Logar M, Kotnik J, Faganeli J, Hines ME, Bonzongo J-C (2002) Geochem Explor Env A 2:287–296

    Article  CAS  Google Scholar 

  5. 5.

    Kotnik J, Horvat M, Dizdarevič T (2005) Atmos Environ 39(39):7570–7579

    Article  CAS  Google Scholar 

  6. 6.

    Grönlund R, Edner H, Svanberg S, Kotnik J, Horvat M (2005) Atmos Environ 39:4067–4074

    Article  Google Scholar 

  7. 7.

    Biester H, Gosar M, Müller G (1999) J Geochem Explor 65(3):195–204

    Article  CAS  Google Scholar 

  8. 8.

    Gosar M, Pirc S, Bidovec M (1997) J Geochem Explor 58(2–3):125–131

    Article  CAS  Google Scholar 

  9. 9.

    Kocman D, Horvat M, Kotnik J (2004) J Environ Monitor 6:696–703

    Article  CAS  Google Scholar 

  10. 10.

    Hines ME, Horvat M, Faganeli J, Bonzongo J-C J, Barkay T, Major EB, Scott KJ, Bailey EA, Warwick JJ, Berry Lyons W (2000) Environ Res 83(2):129–139

    Article  CAS  Google Scholar 

  11. 11.

    Hines ME, Faganeli J, Adatto I, Horvat M (2006) Appl Geochem 21:1924–1939

    Article  CAS  Google Scholar 

  12. 12.

    Žižek S, Horvat M, Gibičar D, Fajon V, Toman MJ (2007) Sci Total Environ 377(2–3):407–415

    Google Scholar 

  13. 13.

    Horvat M, Covelli S, Faganeli J, Logar M, Fajon V, Rajar R, Širca A, Žagar D (1999) Sci Total Environ 237238:43–56

    Article  Google Scholar 

  14. 14.

    Hintelmann H, Keppel-Jones K, Evans RD (2000) Environ Toxicol Chem 19(9):2204–2211

    Article  CAS  Google Scholar 

  15. 15.

    Rodríguez Martín-Doimeadios RC, Tessier E, Amouroux D, Guyoneaud R, Duran R, Caumette P, Donarda OFX (2004) Mar Chem 90:107–123

    Article  Google Scholar 

  16. 16.

    Monperrus M, Tessier E, Point D, Vidimova K, Amouroux D, Guyoneaud R, Leynaert A, Grall J, Chauvaud L, Thouzeau G, Donard OFX (2007) Estuar Coast Shelf S 72:485–496

    Article  CAS  Google Scholar 

  17. 17.

    Guimarães JRD, Malm O, Pfeiffer WC (1995) Sci Total Environ 175:151–162

    Article  Google Scholar 

  18. 18.

    Ribeiro Guevara S, Žižek S, Repinc U, Pérez Catán S, Jaćimović R, Horvat M (2007) Anal Bioanal Chem 387(6):2185–2197

    Article  CAS  Google Scholar 

  19. 19.

    Ramlal PS, Rudd JWM, Hecky RE (1986) Appl Environ Microb 51(1):110–114

    CAS  Google Scholar 

  20. 20.

    Horvat M, Miklavčič V, Pihlar B (1991) Anal Chim Acta 243:71–79

    Article  CAS  Google Scholar 

  21. 21.

    Horvat M, Liang L, Bloom NS (1993) Anal Chim Acta 282:153–168

    Article  CAS  Google Scholar 

  22. 22.

    Kosta L, Byrne AR (1969) Talanta 16:1297–1303

    Article  CAS  Google Scholar 

  23. 23.

    Pérez Catán S, Ribeiro Guevara S, Marvin-DiPasquale M, Magnavacca C, Cohen IM, Arribére M (2007) Appl Radiat Isotopes 65:987–994

    Article  Google Scholar 

  24. 24.

    Ullrich SM, Tanton TW, Abdrashitova SA (2001) Crit Rev Env Sci Tec 31(3):241–293

    Article  CAS  Google Scholar 

  25. 25.

    Weber JH (1993) Chemosphere 26:2063–2077

    Article  CAS  Google Scholar 

  26. 26.

    Nagase H, Ose O, Sato T, Ishikawa T (1982) Sci Total Environ 25:133–142

    Article  CAS  Google Scholar 

  27. 27.

    Gårdfeldt K, Munthe J, Stromberg D, Lindqvist O (2003) Sci Total Environ 304:127–136

    Article  Google Scholar 

  28. 28.

    Craig PJ (ed) (1986) Organometallic components in the environment. Principles and reactions. Longman, Harlow

Download references


This work was implemented in the framework of the bilateral cooperation between Slovenia and Argentina entitled “The production and the use of radiotracers in the biogeochemistry of mercury”, the young researchers programme, the programme P1 – 0143 “Environmental cycling of nutrients and contaminants, mass balance and modelling of environmental processes and risk assessment” and the project L1–7407 “Biological methods as an early warning system in mercury contaminated sites”. The authors also wish to express their gratitude to Dr. Anthony Byrne for his constructive remarks and help with the English language.

Author information



Corresponding author

Correspondence to Suzana Žižek.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Žižek, S., Ribeiro Guevara, S. & Horvat, M. Validation of methodology for determination of the mercury methylation potential in sediments using radiotracers. Anal Bioanal Chem 390, 2115–2122 (2008).

Download citation


  • Mercury
  • Methylmercury
  • Mercury methylation
  • 197Hg radiotracer
  • Sediment