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Exposures of dental professionals to elemental mercury and methylmercury

Journal of Exposure Science & Environmental Epidemiology volume 26, pages 78–85 (2016)Cite this article

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Abstract

Mercury (Hg) exposure, a worldwide public health concern, predominantly takes two forms—methylmercury from fish consumption and elemental Hg from dental amalgam restorations. We recruited 630 dental professionals from an American Dental Association meeting to assess Hg body burden and primary sources of exposure in a dually exposed population. Participants described occupational practices and fish consumption patterns via questionnaire. Hg levels in biomarkers of elemental Hg (urine) and methylmercury (hair and blood) were measured with a Direct Mercury Analyzer-80 and were higher than the general US population. Geometric means (95% CI) were 1.28 (1.19–1.37) μg/l in urine, 0.60 (0.54–0.67) μg/g in hair and 3.67 (3.38–3.98) μg/l in blood. In multivariable linear regression, personal amalgams predicted urine Hg levels along with total years in dentistry, amalgams handled, working hours and sex. Fish consumption patterns predicted hair and blood Hg levels, which were higher among Asians compared with Caucasians. Five species contributed the majority of the estimated Hg intake from fish—swordfish, fresh tuna, white canned tuna, whitefish and king mackerel. When studying populations with occupational exposure to Hg, it is important to assess environmental exposures to both elemental Hg and methylmercury as these constitute a large proportion of total exposure.

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Acknowledgements

We acknowledge the American Dental Association for their support. The University of Michigan (UM) field staff (Amanda Barks, Josillia Johnson and Autumn Poisson) was instrumental in subject recruitment. Lara Khadr and Autumn Poisson were instrumental for Hg analysis, and Maxwell Scher and John Francis for specific gravity analysis. This research was supported by grants from the National Center for Advancing Translational Sciences of the National Institutes of Health (award no. 2UL1TR000433), the UM Office of the Vice President for Research, the UM Environmental Health Sciences Core Center (grant no. P30 ES017885) and the UM School of Public Health. JMG is also supported by US Environmental Protection Agency (US EPA) grants RD834800 and RD83543601 and National Institute for Environmental Health Sciences (NIEHS) grants P20 ES018171, P01 ES02284401. The contents of this publication are solely the responsibility of the grantee and do not necessarily represent the official views of the US EPA or the NIH. Further, the US EPA does not endorse the purchase of any commercial products or services mentioned in the publication.

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Authors and Affiliations

  1. Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan, USA

    Jaclyn M Goodrich & Alfred Franzblau

  2. American Dental Association, Chicago, Illinois, USA

    Hwai-Nan Chou & Stephen E Gruninger

  3. Department of Agriculture and Environmental Sciences, McGill University, Montreal, Quebec, Canada

    Niladri Basu

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  1. Jaclyn M Goodrich
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Correspondence to Jaclyn M Goodrich.

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Supplementary Information accompanies the paper on the Journal of Exposure Science and Environmental Epidemiology website

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Goodrich, J., Chou, HN., Gruninger, S. et al. Exposures of dental professionals to elemental mercury and methylmercury. J Expo Sci Environ Epidemiol 26, 78–85 (2016). https://doi.org/10.1038/jes.2015.52

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