Associations of blood metals and metal mixtures with myocardial enzyme profile: an occupational population-based study in China

Abstract

To investigate cross-sectional association between blood metal mixture and myocardial enzyme profile based on an occupational population. We determined creatine kinase (CK) and creatine kinase-MB (CK-MB), lactate dehydrogenase (LD), α‐hydroxybutyrate dehydrogenase (α‐HBD) and aspartate transaminase (AST) among participants from the manganese-exposed workers healthy cohort (n = 544). Levels of 22 metals in blood cells were determined using inductively coupled plasma mass spectrometry. Least absolute shrinkage and selection operator (LASSO) penalized regression model was utilized for metals screening. Exposure-response relationship between specific metal and myocardial enzyme profile was identified by general liner regression and restricted cubic spline analyses. The overall effect and interactions were evaluated with Bayesian kernel machine regression (BKMR). Manganese was linearly and positively associated with CK (Poverall = 0.019, Pnon-linearity = 0.307), dominating positive overall-effect of mixture exposure (manganese, arsenic and rubidium) on CK level; calcium and zinc were linearly negative associated with LD level (Poverall < 0.05, Pnon-linearity > 0.05) and asserted dominance in the negative overall-effect of metal mixtures (Rubidium, molybdenum, zinc, nickel, cobalt, calcium and magnesium) on LD level. It was interesting to note a “U” shape dose-response relationship of molybdenum with LD level (Poverall < 0.001, Pnon-linearity = 0.488). There was an interaction between age and calcium on LD level (Pinteration = 0.041). Besides, there was an interaction between smoking and molybdenum on LD level (Pinteration = 0.035). Our study provides evidence that metal mixture exposure affects myocardial enzyme profile. Additional investigations are required to confirm these associations and reveal the fundamental mechanisms involved.