Association between blood heavy metals and lung cancer risk: A case-control study in China

Exposure to various metals has been reported to lead to lung cancer. However, few studies focused on the combined effects of metal mixture.

To explore the relationship between metal mixture and lung cancer patients.

Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of 8 heavy metals (V, Cr, Mn, Se, Mo, Cd, Ba and Pb) in serum samples of 86 cases and 105 controls in the Tianjin Lung Cancer Cohort. Logistic regression models were used to estimate the effect of each metal on the risk of lung cancer. The restricted cubic spline function was applied to describe the dose-response relationship between various metal concentrations and lung cancer risk. Bayesian Kernel Machine Regression (BKMR), Weighted Quantile Sum (WQS) and Quantile G-Computation (QGC) were employed to explore the effects of metal mixtures as a whole on lung cancer.

An increased risk of lung cancer was associated with higher blood Mo concentration (adjusted OR = 2.94, 95% CI = 1.03-8.74 for tertile 2 vs. tertile 1). Higher Se concentration in blood may have protective effects on the risk of lung cancer (adjusted OR = 0.18, 95% CI = 0.06-0.51 for tertile 3 vs. tertile 1, p-trend <0.001). In addition, Se and Cd may have an antagonism effect on the occurrence of lung cancer (RERI and 95% CI = -0.95 [-31.77, -0.07]; AP and 95% CI = -0.95 [-5.16 -0.74]). Although the metal mixture did not show a significant effect on lung cancer as a whole, this may be due to the offsetting effect between positive and negative effects.

Our research indicates that Se has a promising anti-cancer application, but it is necessary to prevent the role of Cd that antagonize Se in lung cancer.