Exposure to Mercury in the Population

  • Staffan Skerfving
Part of the Rochester Series on Environmental Toxicity book series (RSET)


In the population, there is uptake of mercury (Hg) as inorganic (mainly elemental Hg vapor, Hgo), and organic (mainly methyl-Hg, MeHg)Hg. We have monitored biologically the uptake of inorganic Hg through measurements of the Hg level in urine (U-Hg) and of MeHg through the Hg level in blood (B-Hg).

Hg exposure may occur from occupational and non-occupational sources. The most prevalent occupational exposure is to Hgo among dental personnel. However, with use of adequate methods, the exposure is low. Thus, in a recent study of 244 dentists and dental nurses, we found that the average U-Hg was only 3.3 μg/g creatinine (range up to 23), which was only slightly higher than the level found in a reference population, 2.0 μg/g crea (up to 10). Considerably higher occupational exposure to Hgo occurs in workers in chloralkali plants and fluorescent-tube factories. Such workers had U-Hg levels up to 78 μg/g crea.

In the general population, without occupational Hg exposure, the main source of exposure to Hgo is usually dental amalgam. In a recent study of 81 subjects, we found that there was a pronounced, and exponential, increase of U-Hg with a rising number of amalgam fillings. In subjects with no fillings, the level corresponded to less than 0.5 μg/g crea, in those with many fillings to 5 μg/g crea. Also, removal of all fillings resulted in a dramatic decrease of U-Hg; after one year, the level was only about 25% of that before removal.

In Sweden, the main source of exposure of MeHg is fish. All fish contain MeHg. However, the levels are particularly high in fish from lakes, rivers, and coastal waters contaminated with Hg. We have recently studied the association between fish intake and Hg exposure in a population of 396 subjects. In subjects who never had fish, the average B-Hg was 1.8 ng/g, in those who had at least two fish meals per week 6.7 ng/g. The importance of fish was also clearly demonstrated by a close association between levels of marine n-3 polyunsaturated fatty acids in serum and B-Hgs. The situation will deteriorate, as acid rain increases the fish MeHg level.


Mercury Concentration Mercury Level Inorganic Mercury Mercury Exposure Fish Intake 
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  1. Ahlguist, M., Bengtsson, G., Furuness, B., Hollender, L. and Lapidus, L., 1988. Number of amalgam fillings in relation to objectively experienced symptoms in a study of Swedish women. Comm. Dent. Oral Epidemiol. 16:227–231.CrossRefGoogle Scholar
  2. Akesson, I., Schütz, A., Attewell, R., Skerfving, S., and Glantz, P. O., 1991 Mercury and selenium status in dental personnel-impact of amalgam work and fillings, Arch. Environ. Health, in press.Google Scholar
  3. Aronsson, A. M., Lind, B., Nylander, M. and Nordberg, M., 1989. Dental amalgam and mercury. Biol. Metals, 2:25–30.CrossRefGoogle Scholar
  4. Barregard, L., Thomasen, Y., Schütz, A. and Marklund, S., 1988. Enzymuria in workers exposed to inorganic mercury. Int. Arch. Occup. Environ. Health, 61:65–69.PubMedCrossRefGoogle Scholar
  5. Birke, G., Hagman, D., Johnels, A. G., Plantin, L. O., Sjöstrand, B., Skerfving, S., Westermark, T., and Österdahl, B., 1972. Studies on humans exposed to methylmercury through fish consumption. Arch. Environ. Health, 25:77–91.PubMedCrossRefGoogle Scholar
  6. Brunmark, P., Skarping, G. and Schütz, A. Submitted for publication. Determination of methylmercury in biological samples using capillary gas chromatography and selected ion monitoring.Google Scholar
  7. Clarkson, T. W., Hursh, J. B., Sager, P. R. and Syversen, T. L. M., 1988a. Mercury, in “Biological Monitoring of Biological Metals”, T.W. Clarkson, L. Friberg, G.F. Nordberg and P.R. Sager, eds., Plenum Press, New York, pp. 199–246.CrossRefGoogle Scholar
  8. Clarkson, T.W., Friberg, L., Hursh, J.B. and Nylander, M. 1988b. The prediction of intake of mercury vapor from amalgams, in “Biological Monitoring of Biological Metals”, T.W. Clarkson, L. Friberg, G.F. Nordberg and P.R. Sager, eds., Plenum Press, New York, pp. 247–264.CrossRefGoogle Scholar
  9. Druet, P., Effect of inorganic mercury on the immune system, in “Advances in Mercury Toxicology”, T. Suzuki, N. Imura, and T.W. Clarkson, eds., Plenum Press, New York, 1991.Google Scholar
  10. Egglestone, D.W. and Nylander, M., 1987. Correlation of dental amalgam with mercury in brain tissue. J. Prosthet. Dent. 58:704–707.CrossRefGoogle Scholar
  11. Einarsson, K., Hellström, K., Schütz, A., Skerfving, S., 1974. Intrabronchial aspiration of metallic mercury. Acta Med. Scand. 195:527–531.PubMedCrossRefGoogle Scholar
  12. Erfurth, E.M., Schütz, A., Nilsson, A. and Skerfving, S., 1990. Normal pituitary hormone response to thyrotropin and gonadotropin releasing hormones in subjects exposed to elemental mercury vapour. Brit. J. Ind. Med. 47:639–644.Google Scholar
  13. Hargreaves, R.J., Evans, J.G., Janota, I., Magos, L. and Cavanagh, J.B., 1988. Persistent mercury in nerve cells 16 years after metallic mercury poisoning. Neuropathol. Appl. Neurobiol. 14:443–452.PubMedCrossRefGoogle Scholar
  14. Hultman, P. and Eneström, S., 1987. The induction of immune complex deposits in mice by peroral and parenteral administration of mercuric chloride: Strain dependent susceptibility. Clin. Exp. Immunol. 67:283–292.PubMedGoogle Scholar
  15. Hultman, P. and Eneström, S., 1988. Mercury induced antinuclear antibodies in mice: characterization and correlation with renal immune complex deposits. Clin. Exp. Immunol. 71:269–274.PubMedGoogle Scholar
  16. Jonsson, E., Nilsson, T., Skerfving, S. and Svensson, P., 1972. Consumption of fish and exposure to methylmercury through fish in Sweden, Var Föda 24:59–69.Google Scholar
  17. Kjellström, T., Kennedy, P., Wallis, S., Stewart, A., Friberg, L., Lind, B., Wutherspoon, P. and Mantell, C., 1989. Physical and mental development of children with prenatal exposure to mercury from fish. Stage 2. Interviews and psychological tests at age 6. National Swedish Environmental Protection Board, Solna, 112 p.Google Scholar
  18. Kosta, L., Byrne, A.R. and Zelenko, V., 1975. Correlation between selenium and mercury in man following exposure to inorganic mercury. Nature, 254:238–239.PubMedCrossRefGoogle Scholar
  19. Langworth, S., Elinder, C.G. and Akesson, A., 1988. Mercury exposure from dental fillings. I. Mercury concentrations in blood and urine. Swed. Dent. J. 12:69–70.PubMedGoogle Scholar
  20. Langworth, S., Röjdmark, S. and Akesson, A., 1990. Normal pituitary response to thyrotropin releasing hormone in dental personnel exposed to mercury. Swed. Dent. J. 14:101–103.PubMedGoogle Scholar
  21. Molin, M., Bergman, B., Marklund, S.L., Schütz, A. and Skerfving, S., 1990. Mercury, selenium and glutathione peroxidase before and after amalgam removal in man. Acta Odont. Scand. 48:189–202.PubMedCrossRefGoogle Scholar
  22. Molin, M., Bergman, B., Marklund, S.L., Schütz, A. and Skerfving, S. The influence of dental amalgam placement on mercury, selenium, and glutathione peroxidase in man. Acta Odont. Scand., in press b.Google Scholar
  23. Molin, M., Marklund, S.L., Burgman, B. and Nilsson, B., 1989. Mercury, selenium, and glutathione peroxidase in dental personnel. Acta Odont. Scand. 47:383–390.PubMedCrossRefGoogle Scholar
  24. Molin, M., Schütz, A., Skerfving, S. and Sallsten, G. Mobilized mercury in subjects with varying exposure to elemental mercury vapour. Int. Arch. Occup. Environ. Health, in press a.Google Scholar
  25. Nilsson, B. and Nilsson, B., 1986a. Mercury in dental practice. I. The working environment of dental personnel and their exposure to mercury vapor. Swed. Dent. J. 10:1–14.PubMedGoogle Scholar
  26. Nilsson, B. and Nilsson, B., 1986b. Mercury in dental practice. II. Urinary mercury excretion in dental personnel. Swed. Dent. J. 10:221–232.PubMedGoogle Scholar
  27. Nordberg, G. and Skerfving, S., 1972. Metabolism, in “Mercury in the Environment. A Toxicological and Epidemiological Appraisal.” L. Friberg and J. Vostal, eds., Chemical Rubber Co., Cleveland, Ohio, pp. 29–91.Google Scholar
  28. Nylander, M. and Weiner, J., 1989. Relaiton between mercury and selenium in pituitary glands of dental staff. Brit. J. Ind. Med. 46:751–752.Google Scholar
  29. Nylander, M., 1990. Accumulation and biotransformation of mercury and its relationship to selenium after exposure to inorganic mercury and methylmercury. A study on individuals with amalgam fillings, dental personnel, and monkeys. Department of Environmental Hygiene, Karolinska Institute, Stockholm, 1990, ISBN 91-628-0092-2. Thesis.Google Scholar
  30. Nylander, M., Friberg, L., Eggleston, D.W., and Björkman, L., 1989. Mercury accumulation in tissues from dental staff and controls in relation to exposure. Swed. Dent. J. 13:235–243.PubMedGoogle Scholar
  31. Nylander, M., Friberg, L. and Lind, B., 1987. Mercury concentrations in the human brain and kidneys in relation to exposure from amalgam fillings. Swed. Dent. J. 11:179–187.PubMedGoogle Scholar
  32. Olsson, S. and Bergman, M., 1987. Letter to the editor. Scand. J. Dent. Res. 66:1288–1289.CrossRefGoogle Scholar
  33. Olstad, M.L. Holland, R.I., Wandel, N. and Pettersen, A.H., 1987. Correlation between amalgam restorations and mercury concentrations in urine. J. Dent. Res. 66:1179–1182.PubMedCrossRefGoogle Scholar
  34. Piikivi, L. and Hänninen, H., 1989. Subjective symptoms and psychological performance of chlor-alkali workers. Scand. J. Work Environ. Health. 15:69–74.PubMedCrossRefGoogle Scholar
  35. Piikivii, L. Hänninen, H., Martelin, T. and Maniere, P., 1984. Psychological performance in long-term exposure to mercury vapors. Scand. J. Work Environ. Health 10:35–41.CrossRefGoogle Scholar
  36. Piikivii, L. and Tolonen, U., 1989. EEG findings in chlor-alkali workers subjected to low long-term exposure to mercury vapors. Brit. J. Ind. Med. 46:370–375.Google Scholar
  37. Roels, H., Abdeladim, S., Ceulemans, E., Lauwerys, R., 1987. Relationshs between the concentrations of mercury in air and in blood and urine in workers exposed to mercury vapor. Ann. Occup. Hyg. 31:135–145.PubMedCrossRefGoogle Scholar
  38. Roels, H., Gennari, J.P., Lauwerys, R., Buchet, J.P., Malchaire, J. and Bernard, A., 1985. Surveillance of workers exposed to mercury vapour: Validation of previously proposed biological threshold limit value for mercury concentration in urine. Am. J. Ind. Med. 7:45–71.PubMedCrossRefGoogle Scholar
  39. Schiele, R., 1988. Quecksilberabgabe aus Amalgam und Quecksilberablagerung in Organismus und Toxikologishe Bewertung, in “Amalgam-Pro und Contra”. G. Knolle, ed., Deutsche Arzte-Verlag, Köin, pp. 123–131.Google Scholar
  40. Schütz, A., Skarping, G. and Skerfving, S., in press. Mercury, in “Trace element analysis in biological specimens ”. M. Stoeppler and R.F.M. Herber, eds. Year Book Medical Publishers, Chicago, Ill, USA.Google Scholar
  41. Schütz, A. and Skerfving, S., 1975. Blood cell ∂-aminolevulinic acid dehydratase activity in humans exposed to methylmercury. Scand. J. Work Environ. Health 1:54–59.PubMedCrossRefGoogle Scholar
  42. Skare, I., Bergström, T., Engqvist, A. and Weiner, J.A., 1990. Mercury exposure of different origins among dentists and dental nurses. Scand. J. Work Environ. Health 16:340–347.PubMedCrossRefGoogle Scholar
  43. Skerfving, S., 1974. Methylmercury exposure, mercury levels in blood and hair, and health status in Swedes consuming contaminated fish. Toxicology 2:3–23.PubMedCrossRefGoogle Scholar
  44. Skerfving, S., 1988. Mercury in women exposed to methylmercury through fish consumption, and in their newborn babies and breast milk. Bull. Environ. Contam. Toxicol. 41:475–482.PubMedCrossRefGoogle Scholar
  45. Skerfving, S., Hansson, K., Mangs, C., Lindsten, I. and Ryman, N., 1974. Methylmercury induced chromosome damage in man. Environ. Res. 7:83–98.CrossRefGoogle Scholar
  46. Stock, A., 1939. Die chronische Quecksilber-und Amalgamvergiftung. Zahnartzl. Rundsch. 48:403–407.Google Scholar
  47. Svensson, B.G., Björnham, A., Schütz, A., Lettewall, U., Nilsson, A. and Skerfving, S., 1987. Acidic deposition and human exposure to toxic metals. Sci. Tot. Environ. 67:101–115.CrossRefGoogle Scholar
  48. Svensson, B.G., Schutz, A., Nilsson, A., Akesson, I., Akesson, B. and Skerfving, S. Fish as a source of exposure to mercury and selenium, Submitted for publication.Google Scholar
  49. Svensson, B.G., Nilsson, A., Rappe, C., Hansson, M., Akesson, B. and Skerfving, S., 1991. Exposure to dioxins and dibenzofurans through fish consumption. N. Engl. J. Med.Google Scholar
  50. WHO, 1990. Environmental Health Criteria 101, Methylmercury, World Health Organization, Geneva, 144 pp.Google Scholar
  51. WHO, 1991. Environmental Health Criteria, Inorganic mercury, World Health Organization, Geneva, 168 pp.Google Scholar

Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Staffan Skerfving
    • 1
  1. 1.Department of Occupational and Environmental MedicineUniversity HospitalLundSweden

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