This study employed an improved global-regional nested Atmospheric Aerosol and Chemistry Model (IAP-AACM) to investigate the global distribution of PAHs and the health risk in 2013 and 2018, respectively. The new developed model includes more parameterized processes and shows satisfied simulation results. The results reveal a decline of PAH concentration in most area of China except Sichuan Basin, attributed to meteorology conditions. However, the total incremental lifetime cancer risk posed by BaP only show a slight decrease and the health risks still exist especially in East China. All the findings indicate more tough control measures for PAH when considering both pollution and public health. Besides, meteorology factors play an important role when assessing the control measures for concentration measuring.

The paper is well structured and contributes importance for air pollution and health risks. However, there are several limitations outlined below that need to be addressed before considering it for publication.

Major comments:

• The title as well as main text of this paper shows the analysis results “ from 2013 to 2018”, while the simulation tests were performed for 2013 and 2018, respectively. Therefore, the expression is ambiguous.

• In abstract, Line 28-29, the study concluded the decrease for BaP is smaller than PM2.5 during the same period. However, it seems no analysis was performed in section4 to support this conclusion.

• Is the computation for TILCR consider the population data for each simulation resolution? From formulation 14-18, there are no population data related but in Line 214-216, the population data were used.

• 9 shows the distribution of TILCR. As shown in formula (18), the TILCR is calculated for children, women and men, respectively. Is the TILSR in Fig.9 calculated with the number of children, women and men as weight? If so, please clarify how to obtain the TILCR in this figure.

• Line 436-437, “It can be seen that the spatial distribution of TILCR (Fig. 9a) is consistent with the spatial distribution of the BaP annual concentrations”. According to the formula (14)-(18), the TILCR seems to be proportional with the concentration of PAHs, as the other parameters have fixed values, so the TILCR should be consistent with Fig.7. The same problem also exists regard to Fig.10. The differences between children, women and men depends on the coefficients in formula (14)-(17). In my understanding, the conclusion can be obtained directly from these formulas. Please elaborate more about the meaning of these two figures.

• In part 4.3, the author wants to show the health risks of PAHs. I think it’s better to add a figure of the distribution of health risk grade in China for a more intuitive understanding.

• Formulation (14) lacks the explanation for parameter AF and CF.

• Line 507, it should be YRD, not YRH.

• 7, the figure annotation has some errors. Simulated concentrations are in orange not red and observed values are in blue not lack, please check.

Title: Modeling of PAHs From Global to Regional Scales: Model Development and Investigation of Health Risks from 2013 to 2018 in China

The study investigates the global distribution of polycyclic aromatic hydrocarbons (PAHs) and their health risks, focusing on China from 2013 to 2018. Using the IAP-AACM model, the authors evaluate the spatial and seasonal distribution of BaP, a key PAH indicator. The authors show BaP concentrations have decreased in China due to emission reductions but increased in India and Southern Africa. Despite the reductions, the health risks in China, particularly in East China, remain significant.

By developing a PAH module, the study offers significant insights into PAH distribution and health risks, providing valuable insights into PAH trends across developing regions. I am happy to see its publication in due course. I would like to suggest some minor revisions after addressing the following questions:

（1）The authors should justify the capability of the EDGAR inventory to capture the short-term emission changes between 2013-2018 at the regional scale.

（2）Figure 8 looks like just a zooming in of Figure 4 with a focus over China. Again, how to verify the very local changes in Figure 8?

（3）In Figures10-12, it is not easy for the readers to understand the abbreviation of each province.

（4）I am wondering what’s the motivation to focus on the PAH health risks over China, and it is possible to include more developing regions?

（5）In terms of PAH control, I suggest to add more policy-related discussions. For example, more specific measures could be proposed.