Manganese (Mn) is an established neurotoxicant with complex pharmacology, due to its role as an essential trace element. This proposal builds on a large body of research generated by our investigative team over the last decade. In these studies, we have demonstrated that: Mn-exposed welders have a high prevalence of parkinsonism compared to a reference population; the phenotype of parkinsonism in Mn-exposed workers overlaps substantially with the phenotype seen in Parkinson disease (PD); Mn-exposed workers have presynaptic dopaminergic dysfunction, thereby linking Mn exposure to the same pathways involved in PD; and there is an increased risk of PD in regions of the U.S. with high industrial Mn emissions. In this proposal, we will perform a population-based epidemiology study of Mn-exposed adults living near a large Mn smelter in Meyerton, South Africa, and of a non-exposed reference community in Kroonstad, South Africa, in which we will compare the prevalence and severity of motor, cognitive control, and mood dysfunction between the two communities. Within the Mn-exposed Meyerton community, we will also investigate the dose-response relationship between environmental Mn exposure and these health outcomes. Our preliminary data clearly support the hypotheses we propose to test and demonstrate that the proposed work is feasible. Our research team is ideally suited to conduct these studies and includes world experts in clinical assessment of Mn neurotoxicity, environmental pollution modeling, and epidemiology. The mixed-race (black and white) South African community to be studied will provide a unique opportunity to investigate racial differences to sensitivity to Mn. Demonstrating motor and cognitive health effects from ambient Mn at exposure levels below the current Environmental Protection Agency lowest observed adverse effect level will have a substantial public health impact by informing environmental regulatory policy in the United States and worldwide.

Public Health Relevance

In this application, we propose to investigate the motor, cognitive, and mood health effects associated with environmental manganese (Mn) exposure from a Mn smelter in a mixed-race South African community. This study will build substantially on prior work by us and others toward understanding the health effects of a common environmental exposure found in all regions of the U.S. and will inform environmental regulatory policy.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES025991-03
Application #
9265097
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Finn, Symma
Project Start
2015-08-01
Project End
2020-04-30
Budget Start
2017-05-01
Budget End
2018-04-30
Support Year
3
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Washington University
Department
Neurology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Ben-Shahar, Yehuda (2017) Epigenetic switch turns on genetic behavioral variations. Proc Natl Acad Sci U S A 114:12365-12367