“…Olfactory dysfunction is regarded as an early warning sign of Parkinson’s disease (Louis et al, 2008, Mollenhauer et al, 2013, Ross et al, 2012), Alzheimer’s Disease (Murphy et al, 1990, Thompson et al, 1998, Wang et al, 2010), and cognitive decline (Royall et al, 2002, Seo et al, 2009, Sohrabi et al, 2012, Swan and Carmelli, 2002). Given that lead, pesticides like DDT and other environmental exposures also show associations with these diseases (Richardson et al, 2014, Richardson et al, 2009, Weisskopf et al, 2010), and are known to be rhinotoxic in occupationally exposed populations and animal models (Sunderman, 2001), it is plausible that environmental exposures such as lead could also be related to olfactory dysfunction.…”