Detection of Benz[<i>j</i>]aceanthrylene in Urban Air and Evaluation of Its Genotoxic Potential

Abstract

Benz­[<i>j</i>]­aceanthrylene (B­[<i>j</i>]­A) is a cyclopenta-fused polycyclic aromatic hydrocarbon with strong mutagenic and carcinogenic effects. We have identified B­[<i>j</i>]­A in air particulate matter (PM) in samples collected in Stockholm, Sweden and in Limeira, Brazil using LC–GC/MS analysis. Determined concentrations ranged between 1.57 and 12.7 and 19.6–30.2 pg/m³ in Stockholm and Limeira, respectively, which was 11–30 times less than benzo­[<i>a</i>]­pyrene (B­[<i>a</i>]­P) concentrations. Activation of the DNA damage response was evaluated after exposure to B­[<i>j</i>]­A in HepG2 cells in comparison to B­[<i>a</i>]­P. We found that significantly lower concentrations of B­[<i>j</i>]­A were needed for an effect on cell viability compared to B­[<i>a</i>]­P, and equimolar exposure resulted in significant more DNA damage with B­[<i>j</i>]­A. Additionally, levels of γH2AX, pChk1, p53, pp53, and p21 proteins were higher in response to B­[<i>j</i>]­A than B­[<i>a</i>]­P. On the basis of dose response induction of pChk1 and γH2AX, B­[<i>j</i>]­A potency was 12.5- and 33.3-fold higher than B­[<i>a</i>]­P, respectively. Although B­[<i>j</i>]­A levels in air were low, including B­[<i>j</i>]­A in the estimation of excess lifetime cancer risk increased the risk up to 2-fold depending on which potency factor for B­[<i>j</i>]­A was applied. Together, our results show that B­[<i>j</i>]­A could be an important contributor to the cancer risk of air PM