Koh Dong-Hee, Jeon Hee-Kyung, Lee Sang-Gil, Ryu Hyang-Woo
Occupational Safety and Health Research Institute, Korea Occupational Safety and Health Agency, Ulsan, Korea [Current affiliation] Department of Occupational and Environmental Medicine, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Korea.
Occupational Safety and Health Research Institute, Korea Occupational Safety and Health Agency, Ulsan, Korea.
Occup Environ Med. 2015 Jun;72(6):421-7. doi: 10.1136/oemed-2014-102227. Epub 2015 Jan 9.
Benzene is a well-known haematological toxin causing aplastic anaemia and leukaemia. Some recent studies have shown that low-level benzene exposure (<1 ppm) disturbs the haematopoietic system. However, other studies showed inconsistent results. The aim of the present study was to examine the relationship between low-level benzene exposure and blood cell counts in Korean workers.
Blood cell counts of benzene-exposed workers were extracted from a nationwide Special Health Examination Database from 2000 to 2008. If a worker did not take a blood test for benzene between 2000 and 2004, the worker was selected for analysis. In total, 8679 personal air benzene measurements were extracted from the nationwide Workplace Environment Measurement Database from 2004 to 2008. Mean benzene levels were calculated and assigned to benzene-exposed workers using various combinations of factory/industry/process codes. Mixed-effects models were used to examine dose-related associations between benzene levels and white blood cell (WBC), red blood cell (RBC), platelet, neutrophil and lymphocyte counts.
In total, 21 140 blood samples were tested from 10 702 workers between 2005 and 2008; 40% of the workers had repeated blood tests (average, 3.4 times). RBC counts in male workers showed a significant negative association with low-level benzene exposure. WBC, platelet, neutrophil and lymphocyte counts did not show a consistent association with low-level benzene exposure.
Our findings support the potential haematotoxicity of low-level benzene exposure (<1 ppm). A longitudinal study with direct benzene measurements for exposed workers is needed to confirm the toxicity of low-level benzene exposure.
苯是一种众所周知的血液毒素，可导致再生障碍性贫血和白血病。最近的一些研究表明，低水平苯暴露（<1 ppm）会扰乱造血系统。然而，其他研究结果并不一致。本研究的目的是探讨韩国工人低水平苯暴露与血细胞计数之间的关系。
从2000年至2008年的全国特殊健康检查数据库中提取苯暴露工人的血细胞计数。如果一名工人在2000年至2004年期间未进行苯血液检测，则选择该工人进行分析。总共从2004年至2008年的全国工作场所环境测量数据库中提取了8679次个人空气苯测量值。计算平均苯水平，并使用工厂/行业/工艺代码的各种组合将其分配给苯暴露工人。采用混合效应模型研究苯水平与白细胞（WBC）、红细胞（RBC）、血小板、中性粒细胞和淋巴细胞计数之间的剂量相关关联。
2005年至2008年期间，共对10702名工人的21140份血液样本进行了检测；40%的工人进行了重复血液检测（平均3.4次）。男性工人的红细胞计数与低水平苯暴露呈显著负相关。白细胞、血小板、中性粒细胞和淋巴细胞计数与低水平苯暴露没有一致的关联。
我们的研究结果支持低水平苯暴露（<1 ppm）的潜在血液毒性。需要对暴露工人进行直接苯测量的纵向研究，以确认低水平苯暴露的毒性。
