Navasumrit Panida, Chanvaivit Sirirat, Intarasunanont Pornpat, Arayasiri Manaswee, Lauhareungpanya Narumon, Parnlob Varaporn, Settachan Daam, Ruchirawat Mathuros
Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Vipavadee Rangsit Highway, Lak Si, Donmuang, Bangkok 10210, Thailand.
Chem Biol Interact. 2005 May 30;153-154:75-83. doi: 10.1016/j.cbi.2005.03.010. Epub 2005 Apr 1.
Exposure to benzene in air is a concern in Thailand, particularly since it was observed that the incidence of blood-related cancers, such as leukemia and lymphoma, has increased in the past few decades. In Bangkok, the mean atmospheric levels of benzene on main roads and in schools were 33.71 and 8.25 ppb, respectively, while in gasoline service stations and petrochemical factories the mean ambient levels were 64.78 and 66.24 ppb, respectively. Cloth vendors (22.61 ppb) and grilled-meat vendors (28.19 ppb) working on the roadsides were exposed to significantly higher levels of benzene than the control group (12.95 ppb; p<0.05). Bangkok school children (5.50 ppb) were exposed to significantly higher levels of benzene than provincial school children (2.54 ppb; p<0.01). Factory workers (73.55 ppb) and gasoline service attendants (121.67 ppb) were exposed to significantly higher levels of benzene than control workers (4.77 ppb; p<0.001). In accordance with the increased benzene exposures, levels of urinary trans,trans-muconic acid (MA) were significantly increased in all benzene-exposed groups. In school children, the levels of MA were relatively high, taking into account the much lower level of exposure. Blood benzene levels were also significantly increased in Bangkok school children (77.97 ppt; p<0.01), gasoline service attendants (641.84 ppt; p<0.05) and factory workers (572.61 ppt; p<0.001), when compared with the respective controls. DNA damage, determined as DNA strand breaks, was found to be elevated in gasoline service attendants, petrochemical factory workers, and Bangkok school children (p<0.001). The cytogenetic challenge assay, which measures DNA repair capacity, showed varying levels of significant increases in the numbers of dicentrics and deletions in gasoline service attendants, petrochemical factory workers and Bangkok school children, indicating a decrease in DNA repair capacity in these subjects.
在泰国，空气中苯的暴露是一个令人担忧的问题，特别是因为据观察，在过去几十年中，白血病和淋巴瘤等血液相关癌症的发病率有所上升。在曼谷，主要道路和学校空气中苯的平均含量分别为33.71 ppb和8.25 ppb，而在加油站和石化工厂，环境空气中苯的平均含量分别为64.78 ppb和66.24 ppb。路边的布商（22.61 ppb）和烤肉摊贩（28.19 ppb）接触苯的水平明显高于对照组（12.95 ppb；p<0.05）。曼谷学童（5.50 ppb）接触苯的水平明显高于省级学童（2.54 ppb；p<0.01）。工厂工人（73.55 ppb）和加油站工作人员（121.67 ppb）接触苯的水平明显高于对照工人（4.77 ppb；p<0.001）。随着苯暴露量的增加，所有苯暴露组尿中反式，反式粘康酸（MA）水平均显著升高。考虑到学童的暴露水平低得多，其MA水平相对较高。与各自的对照组相比，曼谷学童（77.97 ppt；p<0.01）、加油站工作人员（641.84 ppt；p<0.05）和工厂工人（572.61 ppt；p<0.001）的血液苯水平也显著升高。以DNA链断裂来衡量发现汽油服务人员、石化工厂工人和曼谷学童的DNA损伤升高（p<0.001）。测量DNA修复能力的细胞遗传学挑战试验显示，汽油服务人员、石化工厂工人和曼谷学童中的双着丝粒和缺失数量有不同程度的显著增加，表明这些受试者DNA修复能力下降。
