Fig. 5: The main source contributions to VOCs and their potential impacts on O3 formation.

a Source apportionment to consumed VOCs (C-VOCs); and b contributions of different pollution sources to OFPC-VOCs (based on nine reactive species). The highest contributor to C-VOCs is different from the highest contributors to M-VOCs and In-VOCs (Supplementary Fig. 8). This figure shows that focusing on the sources of C-VOCs can capture the real source of VOCs’ effect on O3.