Combination of Unmix and PMF receptor model to apportion the potential sources and contributions of PAHs in wetland soils from Jiaozhou Bay, China

•Jiaozhou Bay wetland is the largest estuarine wetland of Shandong peninsula, China.•The concentrations of 16 PAHs in Jiaozhou Bay wetland soils were firstly reported.•2- and 3-rings PAHs were the dominant PAHs.•Combination of Unmix and PMF model was applied to estimate source contribution of PAHs.•Petrogenic source was the most significant source with the highest contribution.

16 PAHs in Jiaozhou Bay wetland soils were analyzed by GC/MS. The potential sources and contributions were apportioned by Unmix and PMF models. The total concentrations of PAHs ranged from 176.1 to 563.3 ng/g with a mean of 345.3 ng/g. 2- and 3- rings PAHs were the dominant species accounting for 34.7-87.3% of the total PAHs. The similarities and differences of sources and contributions estimated by Unmix and PMF models were discussed. Three common sources (petrogenic source, coking oven and coal combustion) identified by two models, contributed 43.2%, 39.2% and 12.6% by Unmix and 33.5%, 29.1% and 16.0% by PMF to the total PAHs, respectively. In addition, diesel emission source (5.0%) by Unmix and a mixed source of diesel emission and natural gas burning (21.4%) by PMF were also extracted. It is essential to apply multiple source apportionment techniques to estimate potential source and contributions in further study.