Comprehensive Analysis of Toxic Metal Exposure in ALS Patients in South Korea Using Hair Analysis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with an unclear etiology. Emerging evidence suggests that heavy metal exposure may contribute to its development. Objective: This study aims to compare hair concentrations of heavy metals between ALS patients and healthy controls in South Korea to explore potential associations. Methods: Hair samples were collected from 66 ALS patients and 60 healthy individuals at Rodem Hospital between 2022 and 2025. Inductively coupled plasma mass spectrometry (ICP-MS) was utilized to measure levels of mercury (Hg), lead (Pb), cadmium (Cd), aluminum (Al), arsenic (As), and other potentially harmful metals including uranium (U). Results: ALS patients exhibited significantly higher mean concentrations of Hg, Pb, Cd, Al, As, and U in hair samples compared to controls (p < 0.05). Notably, 40% of ALS patients had Hg levels exceeding 50% of the reference upper limit, whereas only 10% of controls showed similar levels. Elevated levels of uranium and other rare metals were identified in specific cases. Conclusion: The findings indicate that ALS patients in South Korea have elevated hair concentrations of specific heavy metals, supporting the hypothesis that heavy metal exposure may be linked to ALS pathogenesis. Further research is warranted to elucidate the mechanisms underlying this association.