Comparison of Blood and Brain Mercury Levels in Infant Monkeys Exposed to Methylmercury or Vaccines Containing Thimerosal

Burbacher, Thomas M.; Shen, Danny D.; Liberato, Noelle; Grant, Kimberly S.; Cernichiari, Elsa; Clarkson, Thomas
August 2005
Environmental Health Perspectives;Aug2005, Vol. 113 Issue 8, p1015
Academic Journal
Thimerosal is a preservative that has been used in manufacturing vaccines since the 1930s. Reports have indicated that infants can receive ethylmercury (in the form of thimerosal) at or above the U.S. Environmental Protection Agency guidelines for methylmercury exposure, depending on the exact vaccinations, schedule, and size of the infant. In this study we compared the systemic disposition and brain distribution of total and inorganic mercury in infant monkeys after thimerosal exposure with those exposed to MeHg. Monkeys were exposed to MeHg (via oral gavage) or vaccines containing thimerosal (via intramuscular injection) at birth and 1, 2, and 3 weeks of age. Total blood Hg levels were determined 2, 4, and 7 days after each exposure. Total and inorganic brain Hg levels were assessed 2, 4, 7, or 28 days after the last exposure. The initial and terminal half-life of Hg in blood after thimerosal exposure was 2.1 and 8.6 days, respectively, which are significantly shorter than the elimination half-life of Hg after MeHg exposure at 21.5 days. Brain concentrations of total Hg were significantly lower by approximately 3-fold for the thimerosal-exposed monkeys when compared with the MeHg infants, whereas the average brain-to-blood concentration ratio was slightly higher for the thimerosal-exposed monkeys (3.5 ± 0.5 vs. 2.5 ± 0.3). A higher percentage of the total Hg in the brain was in the form of inorganic Hg for the thimerosal-exposed monkeys (34% vs. 7%). The results indicate that MeHg is not a suitable reference for risk assessment from exposure to thimerosal-derived Hg. Knowledge of the toxicokinetics and developmental toxicity of thimerosal is needed to afford a meaningful assessment of the developmental effects of thimerosal-containing vaccines.


Related Articles

  • Thimerosal and Animal Brains. Barrett, Julia R. // Environmental Health Perspectives;Aug2005, Vol. 113 Issue 8, pA543 

    This article focuses on an animal study showing methylmercury to be an inadequate reference for ethylmercury due to significant differences in tissue distribution, clearance rates, and ratios of organic to inorganic mercury in the brain. Since the 1930s, vaccines have contained thimerosal, a...

  • Effects of Environmental Agents on the Attainment of Puberty: Considerations When Assessing Exposure to Environmental Chemicals in the National Children's Study. Wang, Richard Y.; Needham, Larry L.; Barr, Dana B. // Environmental Health Perspectives;Aug2005, Vol. 113 Issue 8, p1100 

    The apparent decline in the age at puberty in the United States raises a general level of concern because of the potential clinical and social consequences of such an event. Nutritional status, genetic predisposition (race/ethnicity), and environmental chemicals are associated with altered age...

  • Biologic Monitoring of Exposure to Environmental Chemicals throughout the Life Stages: Requirements and Issues for Consideration for the National Children's Study. Barr, Dana B.; Wang, Richard Y.; Needham, Larry L. // Environmental Health Perspectives;Aug2005, Vol. 113 Issue 8, p1083 

    Biomonitoring of exposure is a useful tool for assessing environmental exposures. The matrices available for analyses include blood, urine, breast milk, adipose tissue, and saliva, among others. The sampling can be staged to represent the particular time period of concern: preconceptionally from...

  • MANAGING ENVIRONMENTAL RISKS IN PRODUCTION COMPANIES. Rovnak, Martin; Chovancova, Jana; Bednarova, Lucia; Adamisin, Peter; Huttmanová, Emília // Proceedings of the International Multidisciplinary Scientific Ge;2013, p651 

    Extensive industrial production, implementation of new technologies, using of growing number of dangerous substances in production processes brings remarkable risks tightly related to health and environmental threads. In the submitted article authors present an approach of the environmental risk...

  • Exposure Assessment Implications for the Design and Implementation of the National Children's Study. Özkaynak, Halûk; Whyatt, Robin M.; Needham, Larry L.; Akland, Gerry; Quackenboss, James // Environmental Health Perspectives;Aug2005, Vol. 113 Issue 8, p1108 

    Examining the influence of environmental exposures on various health indices is a critical component of the planned National Children's Study (NCS). An ideal strategy for the exposure monitoring component of the NCS is to measure indoor and outdoor concentrations and personal exposures of...

  • Umbilical Cord Mercury Concentration as Biomarker of Prenatal Exposure to Methylmercury. Grandjean, Philippe; Budtz-Jørgensen, Esben; Jørgensen, Poul J.; Weihe, Pál // Environmental Health Perspectives;Jul2005, Vol. 113 Issue 7, p905 

    Biomarkers are often applied to assess prenatal exposure to methylmercury in research and surveillance. In a prospective study in the Faroe Islands, the main exposure biomarkers were the mercury concentrations in cord blood and maternal hair obtained at parturition. We have now supplemented...

  • Personalized Exposure Assessment: Promising Approaches for Human Environmental Health Research. Weis, Brenda K.; Balshaw, David; Barr, John R.; Brown, David; Ellisman, Mark; Lioy, Paul; Omenn, Gilbert; Potter, John D.; Smith, Martyn T.; Sohn, Lydia; Suk, William A.; Sumner, Susan; Swenberg, James; Walt, David R.; Watkins, Simon; Thompson, Claudia; Wilson, Samuel H. // Environmental Health Perspectives;Jul2005, Vol. 113 Issue 7, p840 

    New technologies and methods for assessing human exposure to chemicals, dietary and lifestyle factors, infectious agents, and other stressors provide an opportunity to extend the range of human health investigations and advance our understanding of the relationship between environmental exposure...

  • Review of criteria for evaluating LCA weighting methods. Johnsen, Fredrik; Løkke, Søren // International Journal of Life Cycle Assessment;May2013, Vol. 18 Issue 4, p840 

    Purpose: In the process of selecting where effective environmental measures should be directed, the weighting step of life cycle assessment (LCA) is an optional, controversial, but nevertheless important tool. A set of criteria for evaluating weighting methods has relevance in the process of...

  • EIA reforms could speed up planning.  // ENDS (Environmental Data Services);Nov2012, Issue 454, p41 

    The article discusses potential impact of environmental impact assessment (EIA) reforms on major planning applications in Great Britain. It is said that improvements to EIA could be beneficial to both planning authorities and developers. Brief details about the Growth and Infrastructure Bill...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics