Single and mixed effects of multiple volatile organic compounds exposure on hematological parameters in the U.S. adult population

Background: Most research exploring the correlation between volatile organic compounds (VOCs) and hematological parameters have focused on single VOCs. Our study aimed to explore the single and combined effects of VOCs on hematological parameters through three statistical models. Methods: Data from 4 cycles of the National Health and Nutrition Examination Survey (NHANES) were used in this study. The correlations between single exposure to 16 VOCs and hematological parameters in the general population were assessed by weighted multiple linear regression. Weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models were used to explore the relationship between the combined important VOCs selected by the least absolute shrinkage and selection operator (LASSO) and hematological parameters, as well as the effects of smoking status on them. Results: A total of 4089 adults were included in the study. We found that a variety of VOCs were significantly associated with hematological parameters. Among them, N-acetyl-S-(benzyl)-L-cysteine (BMA) was significantly negatively correlated with white blood cell (WBC), red blood cell (RBC), lymphocyte, and neutrophil counts. N-acetyl-S-(3-hydroxypropyl-1-methyl)-L-cysteine (HPMMA) was significantly positively correlated with WBC, monocyte, lymphocyte, and neutrophil counts. In the WQS analysis, the WQS index of the VOCs mixtures was positively correlated with WBC (β: 0.031; P < 0.001), monocyte (0.023; P = 0.021), and neutrophil (0.040; P = 0.001) counts, while negatively associated with RBC (−0.013; P < 0.001) counts. The BKMR model revealed that combined exposure to VOCs levels ≥70th percentile was significantly associated with lower RBC counts, and BMA was identified as the dominant contributor. Smoking significantly influenced the relationship between VOCs and hematological parameters. Conclusions: Our study indicated the effects of single and overall VOCs exposure on hematological parameters and suggested the hematotoxicity as well as pro-inflammatory effects of VOCs, which had strong public health implications for reducing the potential health hazards of VOCs exposure to the hematologic system.