Wildfires as a Source of PAHs in Surface Waters of Background Areas (Lake Baikal, Russia)

Polycyclic aromatic hydrocarbons (PAHs) were detected in different types of PAH-containing samples collected Lake Baikal during wildfires the adjacent areas. The set studied included following: (i) water from upper layer (5 m); (ii) surface microlayer; (iii) lake tributaries; (iv) deep layers (400 and (v) aerosol near-water layer. Ten PAHs samples: naphthalene, 1-methylnaphthalene, 2-methylnaphthalene acenaphthylene, acenaphthene, fluorene, phenanthrene, fluoranthene, pyrene, chrysene. total PAH concentrations (ƩPAHs) a wide range 9.3 to 160 ng/L, characterizing by seasonal, intersessional, spatial variability. In September 2016, ƩPAH concentration southern basin reached 610 ng/L due an increase pyrene composition PAHs. June 2019, ƩPAHs northern 290 with naphthalene phenanthrene up 170 92 respectively. calculation back trajectories atmospheric transport near Baikal, satellite images, microlayer 150 960 confirm impact on which seasonal was associated 2016 2019. toxicity extreme situations characterized value toxic equivalent for ranging 0.17 0.22 possible ecological risk biota assessed as moderate.