Olfactory functions at the intersection between environmental exposure Q1 tomanganese and Parkinsonism

The olfactory function can be affected by occupational and environmental exposure to various neurotoxicants
that can be transported through the olfactory pathway. Olfactory impairment is a highly recurrent
non-motor dysfunction in Parkinson’s disease and is considered an early predictive sign of neurodegeneration.
Changes in olfactory perception may be caused by a dopaminergic dysregulation, possibly related
to changes at the level of dopamine receptors. Manganese is an essential element that can become neurotoxic
in various conditions inducing an overload in the organism. Being actively transported through
the olfactory tract, manganese can cause impairment of olfactory function and motor coordination in
different age groups like children and elderly. Odor and motor changes are interrelated and may be
caused by a Mn-induced dopaminergic dysregulation affecting both functions. Given these findings, further
research is imperative on the possible role of manganese exposure as a pathogenetic factor for
Parkinsonism.