Carcinogenesis Advance Access originally published online on October 27, 2006
Carcinogenesis 2007 28(4):816-822; doi:10.1093/carcin/bgl175
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Increased health risk in Bangkok children exposed to polycyclic aromatic hydrocarbons from traffic-related sources
1 Laboratory of Environmental Toxicology, Chulabhorn Research Institute Bangkok, Thailand
2 Laboratory of Chemical Carcinogenesis, Chulabhorn Research Institute Bangkok, Thailand
3 Department of Environmental and Occupational Medicine, Institute of Public Health, University of Aarhus Aarhus, Denmark
4 Department of Pharmacology, Faculty of Science, Mahidol University Bangkok, Thailand
*To whom correspondence should be addressed at: Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210, Thailand. Tel: +66 2 574 0615; Fax: +66 2 574 0616; Email: mathuros{at}cri.or.th
The aim of this study is to assess potential health risk of exposure to particle-associated polycyclic aromatic hydrocarbons (PAHs) in children living in a megacity with traffic congestion such as Bangkok. The study population comprised 184 Thai schoolboys (aged 8–13 years) attending schools adjacent to high-density traffic areas in Bangkok and schools located in the provincial area of Chonburi. The ambient concentration of total PAHs at roadsides in proximity to the Bangkok schools was 30-fold greater than at roadsides in proximity to the provincial schools (30.39 ± 5.80 versus 1.50 ± 0.28 ng/m3; P < 0.001). Benzo(g,h,i)perylene (BghiP), an indicator of automobile exhaust emission, was the predominant PAH. Personal exposure to total PAHs and the corresponding benzo(a)pyrene (BaP) equivalent concentrations in Bangkok schoolchildren were 3.5-fold higher than in provincial schoolchildren (4.13 ± 0.21 versus 1.18 ± 0.09 ng/m3; P < 0.001 and 1.50 ± 0.12 versus 0.43 ± 0.05 ng/m3; P < 0.001, respectively). The concentration of urinary 1-hydroxypyrene (1-HOP) was significantly higher in Bangkok schoolchildren. Bulky carcinogen–DNA adduct levels in peripheral lymphocytes were also significantly higher (0.45 ± 0.03 versus 0.09 ± 0.00 adducts/108 nt; P < 0.001). Finally, a significantly higher level of DNA strand breaks and a significantly lower level of DNA repair capacity were observed in Bangkok schoolchildren (P < 0.001). This study indicates that Bangkok schoolchildren exposed to a high level of genotoxic PAHs in ambient air may be more vulnerable to the health impacts associated with the exposure to genotoxic pollutants than children in provincial areas and may have increased health risks for the development of certain diseases such as cancer.
Abbreviations: PAHs, polycyclic aromatic hydrocarbons; 1-HOP, 1-hydroxypyrene; BaP, benzo(a)pyrene; BghiP, Benzo(g,h,i)perylene.
Received May 26, 2006; revised August 28, 2006; accepted September 2, 2006.