Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a devastating neurodegenerative disease that attacks motor neurons, causing progressive paralysis and eventually death. ALS has no cure, but researchers are racing to find treatments. This project, however, takes a step back to focus on understanding the underlying causes with the ultimate goal of prevention. While genetic mutations are known to cause ALS in about 10% of cases (familial ALS), the triggers for the remaining 90% of cases (sporadic ALS) remain largely unknown. Interestingly, certain populations, such as military veterans and farmers, appear to have a higher risk of developing sporadic ALS. This suggests that environmental factors may be important in triggering the disease in genetically susceptible individuals. Using advanced disease modeling techniques, this project aims to investigate whether environmental factors, such as exposure to air pollutants or pesticides, can trigger the disease in neurons of individuals with sporadic ALS.