Long-term environmental surveillance of PM2.5-bound polycyclic aromatic hydrocarbons in Jinan, China (2014-2020): Health risk assessment

We established long-term surveillance sites in Jinan city to monitor PM2.5 particles (PM2.5) and PM2.5-bound PAHs (2014-2020). The range of PM2.5 was 15-230 mu g/m3. The average annual PAH16 were 433 +/- 271 ng/ m3 (industrial area) and 299 +/- 171.8 ng/m3 (downtown). PAHs captured in winter accounted for 61.5% (industrial area) and 59.1% (downtown) of total PAHs. A hazardous seasonal benzo[a]pyrene level was detected in 2015-2016 winter as 14.03 ng/m3 (14 folds of EU standard). The dominant PM2.5-bound PAHs were benzo[b] fluoranthene (24-26%), chrysene (19-20%), benzo[g,h,i]perylene (15%), Indeno(1,2,3-cd)pyrene (12%) and Benzo[a]pyrene (10%). Toxic equivalent quotients of PAHs were 4.93 ng/m3 (industrial area) and 3.13 ng/m3 (downtown). Excess cancer risks (ECRs) were 4.3 x 10-4 ng/m3 and 2.7 x 10-4 ng/m3, respectively. The ECRs exceeded EPA regulatory limit of 1 x 10-6 ng/m3 largely. Non-negligible excess lifetime cancer risks were found as 36 and 26 related cancer incidences per 1,000,000 people. Consistently, local prevalence of lung cancer raise from 56.97/100,000 to 72.38/100,000; the prevalence of thyroid cancer raise from 10.12/100,000 to 45.26/ 100,000 from 2014 to 2020. Our findings suggest an urgent need to investigate the adverse health effects of PAHs on local population and we call for more strictly restriction on coal consumption and traffic tail gas emission.