Interstitial lung disorders in the indium workers of Korea: An update study for the relationship with biological exposure indices

Abstract

Korea is one of the highest indium-consuming countries worldwide. The present study aims to determine the relationship between interstitial lung disorders and indium exposure in Korea. In 50 indium workers from seven plants, the effect of serum indium on the lungs was determined using laboratory tests, spirometry, and high-resolution computed tomography (HRCT). Higher serum indium and Krebs von den Lungen-6 (KL-6) levels were associated with HRCT-detected interstitial lung changes. Workers with high serum indium levels (≥3 µg/L) had longer exposure durations and a higher prevalence of HRCT-detected interstitial lung changes. KL-6 and surfactant protein-D (SP-D) levels were significantly higher in the highest serum indium quartile than the lowest quartile. Significant dose-effect relationships existed between serum indium levels and KL-6, SP-D levels and the prevalence of HRCT-detected interstitial lung changes. Workforce medical surveillance should be established to prevent indium-induced interstitial lung disease in Korea.