Exposure and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons for Motorcycle Mechanics
Jyun-De. Wu Tzu-Ting Yang Wei-Yu Lin Tser- Sheng Lin
A total of 16 polycyclic aromatic hydrocarbons (PAHs) in gas and particle phasewere quantified in 20 motorcycle repair workshops (Taiwan). The average indoor gaseousand particle PAHs levels were 3,690 ± 1,457 and 38.3 ± 15.3 ng/m3, respectively. Theestimated benzo[a]pyrene equivalent (BaPeq) was 29.6 ± 33.0 ng/m3, correspondingto a lung cancer risk of 2.1×10-3. Low-molecular-weight PAHs existed primarily inthe gas phase, whereas high-molecular-weight PAHs were a significant fraction of thetotal particle phase PAHs. Naphthalene was the predominated species at 99.9% of the total PAHs, consistent with measured PAHs emissions from motorcycles of differentengine types. The indoor/outdoor (I/O) ratio of naphthalene was 1.54, indicating thatthis particular PAHs was generated by the maintenance and repair activities inside themotorcycle workshops rather than from outdoor motor vehicle emissions. Residentsliving in homes over a motorcycle workshop might be exposed to PAHs for longerdurations than mechanics, thus their potential exposure and related health risk warrants afurther detailed investigation.