Common Herbicide Reduces Sense of Smell in Mice at Low Doses, Implications for Parkinson’s Disease

February 18, 2021 | Research published in the journal Toxicological Sciences finds extended inhalation of the common agricultural herbicide paraquat causes male mice to lose some sense of smell, even at low doses. This study highlights the significance of understanding how specific chemical exposure routes can influence disease development. Olfactory (relating to the sense of smell) impairment is a precursory feature of Parkinson’s disease (PD), and studies connect paraquat poisoning to PD risk. The study’s researchers note, “These data support the importance of route of exposure in the determination of safety estimates for neurotoxic pesticides, such as [paraquat]. Accurate estimation of the relationship between exposure and internal dose is critical for risk assessment and public health protection.” [Timothy Anderson et al. Paraquat Inhalation, A Translationally Relevant Route of Exposure: Disposition to the Brain and Male-Specific Olfactory Impairment in Mice. Toxicological Sciences. 180(1):175, 2021.]