Food Safety and Health Research Center, Guangdong Provincial Key Laboratory of Tropical Disease Research, Guangdong-Hongkong-Macao Joint Laboratory for Contaminants Exposure and Health, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510000, China.
Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong, 510000, China.
Chemosphere. 2022 Dec;308(Pt 1):135946. doi: 10.1016/j.chemosphere.2022.135946. Epub 2022 Aug 22.
Experimental evidence suggests that exposure to cadmium (Cd) could affect immune cells in vivo and in vitro. However, the associations of long-term Cd exposure with white blood cell (WBC) subtype counts and hemogram-derived indices have been rarely investigated. Therefore, we evaluated these relationships in residents of cadmium-polluted areas.
This cross-sectional study included 431 participants aged 45-75 years without occupational exposure histories from Cd-contaminated areas of southern China. We detected WBC, neutrophil, lymphocyte, and monocyte counts using routine blood tests and calculated neutrophil-lymphocyte ratio (NLR), systemic inflammation response index (SIRI), and lymphocyte-monocyte ratio (LMR). Urinary Cd (U-Cd) was measured with inductively coupled plasma mass spectrometry and adjusted for creatinine. To evaluate the associations of U-Cd with peripheral WBC subtype counts and indices, we performed multivariate linear regression, logistic regression and subgroup analyses using U-Cd categorized into quartiles.
In models adjusted for all potential confounders, U-Cd was negatively associated with WBC, neutrophil, and monocyte counts in Q2, compared with Q1 of U-Cd (p < 0.05). A similar relationship was observed between U-Cd and NLR and SIRI, whereas the corresponding association for LMR was positive (p < 0.05). In subgroup analyses, U-Cd was negatively associated with neutrophil count, except for never smokers, after full adjustment.
U-Cd was negatively associated with WBC count, neutrophil count, monocyte count, NLR, and SIRI, and positively associated with LMR. Therefore, neutrophil count could be a potential indicator of long-term Cd exposure-associated immunosuppressive effect.
实验证据表明，接触镉（Cd）会影响体内和体外的免疫细胞。然而，长期 Cd 暴露与白细胞（WBC）亚型计数和血液学衍生指标之间的关联很少被研究。因此，我们评估了这些在镉污染地区居民中的关系。
这项横断面研究纳入了来自中国南方镉污染地区的 431 名 45-75 岁无职业暴露史的参与者。我们使用常规血液检测检测 WBC、中性粒细胞、淋巴细胞和单核细胞计数，并计算中性粒细胞-淋巴细胞比值（NLR）、全身炎症反应指数（SIRI）和淋巴细胞-单核细胞比值（LMR）。使用电感耦合等离子体质谱法检测尿镉（U-Cd），并根据肌酐进行调整。为了评估 U-Cd 与外周 WBC 亚型计数和指标的关联，我们使用 U-Cd 分为四分位数的多元线性回归、逻辑回归和亚组分析进行分析。
在调整了所有潜在混杂因素的模型中，与 U-Cd 四分位第 1 位相比，U-Cd 与第 2 位的 WBC、中性粒细胞和单核细胞计数呈负相关（p < 0.05）。在 U-Cd 与 NLR 和 SIRI 之间也观察到了类似的关系，而 LMR 的对应关联呈阳性（p < 0.05）。在亚组分析中，在充分调整后，除从不吸烟者外，U-Cd 与中性粒细胞计数呈负相关。
U-Cd 与 WBC 计数、中性粒细胞计数、单核细胞计数、NLR 和 SIRI 呈负相关，与 LMR 呈正相关。因此，中性粒细胞计数可能是长期 Cd 暴露相关免疫抑制作用的潜在指标。
