Effects of short-term ambient PM2.5 exposure on the blood cell count and hemoglobin concentration among 82,431 people in eastern China

Abstract

Air pollution has posed a considerable threat to human health. To explore the effects of short-term PM2.5 exposure on peripheral blood cell count and hemoglobin, we performed a correlation study on a large sample of Chinese people who took part in routine physical examinations in eastern China. We enrolled 82,431 participants from the Health Management Center of the First Affiliated Hospital of Nanjing Medical University in 2018. Routine blood test data, including the red blood cell (RBC), white blood cell (WBC) and platelet counts and hemoglobin concentration, were collected. We also extracted data on daily meteorological factors and air pollutants from December 21, 2017, to December 31, 2018, from the National Meteorological Data Sharing Center or the China Air Quality Online Monitoring and Analysis Platform. The generalized additive model was applied to estimate the associations between short-term ambient PM2.5 exposure and the blood cell count and hemoglobin concentration. For a 10 μg/m3 increase in PM2.5, the red blood cell count decreased by 0.005 × 1012/L [95% confidence interval (CI): −0.006, −0.003], the hemoglobin concentration decreased by 0.123 g/L (95% CI: −0.165, −0.081), the lymphocyte count increased by 0.126% (95% CI: 0.021, 0.231), and the monocyte count decreased by 0.434% (95% CI: −0.569, −0.298). After excluding people with abnormal blood test results, the association remained significant. Additionally, the effect could be modified by sex, age, body mass index, and smoking status. Short-term ambient PM2.5 exposure is negatively correlated with the RBC count, hemoglobin concentration, and monocyte count and positively correlated with the lymphocyte count, suggesting that PM2.5 has multiple effects on health.