P-099 the Risk of Beta-2-Microglobulinuria Increases With the Blood Cadmium Level in Japanese Cadmium Workers

Introduction The kidneys, especially the proximal tubules, are most sensitive to cadmium. The objective of this study was to elucidate the relationship between occupational exposure to cadmium and renal damage in Japanese cadmium workers. Methods A dataset of 4080 cases was collected from nickel cadmium battery plants between 1997 and 2020. Blood cadmium (Cd-B) was used as an exposure indicator and urinary β2-microglobulin (B2M-U) as an indicator of renal damage. Cd-B < 1 μg/L was set as the control and ≥ 1 μg/L as the 5 quintiles of exposure groups (< 1.51, < 2.11, < 2.81, < 4.12, and ≥ 4.12). β2-microglobulinuria was defined as exceeding 360 μg/gCr, which was calculated from the mean + 2SD of B2M-U of the control. The Cd-B groups, age, urinary cadmium, smoking, and sex were analyzed for the odds ratio of β2-microglobulinuria using a multivariable logistic regression model. Results Among the 4080 cases, 267 (6.5%) had β2-microglobulinuria, composed of 11 (2.3%) in the control and 256 (7.6%) in the exposure group. The significant increases in adjusted odds ratio for β2-microglobulinuria compared to the control were observed in the groups higher than the central group of the quintile. Discussion Increased odds ratios for β2-microglobulinuria were observed in the groups with Cd-B of 2.1 μg/L or higher in the Japanese plants. Because high B2M-U is an independent risk factor for rapid decline in eGFR, improved management is recommended in Japanese cadmium plants. ù Conclusion A significant increased risk of β2-microglobulinuria was observed at high Cd-B levels among Japanese cadmium workers.