ToxSci Advance Access originally published online on July 14, 2004
Toxicological Sciences 2004 81(2):354-363; doi:10.1093/toxsci/kfh220
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Toxicological Sciences vol. 81 no. 2 © Society of Toxicology 2004; all rights reserved.
Chronic Low-Level Mercury Exposure, BDNF Polymorphism, and Associations with Self-Reported Symptoms and Mood
,1
* Battelle Centers for Public Health Research and Evaluation, Seattle, Washington; and Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington
Received April 23, 2004; accepted July 7, 2004
Recent reports have described neurobehavioral impairments in human subjects carrying a V66M polymorphism in the gene encoding brain-derived neurotrophic factor (BDNF). Inasmuch as ventral nervous system (CNS) deficits associated with this BDNF polymorphism are similar to those observed among subjects with chronic exposure to elemental mercury (Hg°), we examined the potential effect of this BDNF polymorphism on symptoms and mood in an established cohort of dental practitioners with chronic low-level Hg° exposure. Self-reported symptoms and mood were obtained by computerized questionnaire from 193 male dentists (DTs) and 230 female dental assistants (DAs). Spot urine samples were analyzed for mercury concentrations to evaluate recent exposure. Detailed work histories were obtained to calculate chronic indices of Hg° exposure. Buccal cell samples were obtained to identify the V66M polymorphism of BDNF. Scores for 11 current and 12 recent and chronic symptom groups, along with six mood factors, were evaluated with respect to recent and chronic Hg° exposure and BDNF polymorphism. Multiple regression analysis controlled for age, race, socioeconomic status, tobacco and alcohol use, self-reported health problems, and medications. Separate evaluations were conducted for DTs and DAs. Twenty-three associations between recent or chronic Hg° exposure and BDNF status and self-reported symptoms were observed with p < 0.10. All but three were in the expected direction (symptom scores increasing with Hg° exposure or BDNF polymorphism), and all but six were among DAs. All eight correlations between chronic exposure indices and recent and chronic symptoms among DAs were in the expected direction. All seven associations between BDNF and symptoms were in the expected direction and split between DTs and DAs. All three associations with mood factors were among DAs and in the expected direction. These results indicate that among DAs very low levels of occupational Hg° exposure are associated with increased symptoms. The BDNF polymorphism is also associated with increased symptom and mood scores. Notably, Hg° and BDNF polymorphism were additive with respect to their associations with the same symptom group.
Key Words: mercury; brain-derived neurotrophic factor; BDNF; polymorphism; mood; symptoms; neurobehavioral.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  J. Gattineni, S. Weiser, A. M. Becker, and M. Baum Mercury Intoxication: Lack of Correlation Between Symptoms and Levels Clinical Pediatrics, December 1, 2007; 46(9): 844 - 846. [Abstract] [PDF]
|
|