Biomonitoring of Atmospheric PAHs and PMs Using Xanthoria parietina and Cupressus sempervirens in Bouira (Algeria)

Air pollution constitutes a major environmental risk factor for living beings. Protection against such risk needs air pollution monitoring and control. Air pollution monitoring can be obtained in several ways. Amongst them, passive methods assessing cumulative exposure are of particular interest. A passive approach consisting of ambient concentrations biomonitoring of polycyclic aromatic hydrocarbons (PAHs) using lichens and plants was used for assessment of ambient air pollution exposure in the industrial region of Oued El Berdi in Bouira (Algeria). Seven stations were chosen to take samples of lichen thalli of Xanthoria parietina and conifer scales and barks of Cupressus sempervirens in April 2018. The physiological parameters of the chlorophyll and the proline content were measured, and the atmospheric PAHs and particulate matter (PM) concentrations were quantified. The results show a spatial variation between the different stations and directions. The PAH concentrations accumulated in lichen range from 35 ± 3 ng/g dw to 2222 ± 376 ng/g dw and show significant differences ( p = 0.017). These concentrations are higher than those found in conifer scales (18.8 ± 7 dw to 1183.5 ± 876 ng/g dw) and that found in conifer barks (7 ± 3 dw to 515.3 ± 19 ng/g dw). Significant difference between the reference stations of Tikjda and Errich and the five industrial stations of Oued El Berdi were also observed. Physiological parameters (chlorophyll a, chlorophyll b, chlorophyll ab) and proline and air pollutants accumulated (PAHs and PM) were associated. Biomonitoring allowed to show that the industrial area of Oued El Berdi was impacted by PAHs and PM, which are generated mainly by factories located there.