Human Health Risks and Interference of Urban Landscape and Meteorological Parameters in the Distribution of Pollutant: A Case Study of Nakhon Si Thammarat Province, Thailand
, Jenjira Kaewrat 1,2,*, Wittaya Tala 3,4,*, Surasak Sichum 2, Chuthamat Rattikansukha 1,2 and K. H. Sameera M. Dharmadasa 5
Round 1
Reviewer 1 Report
1- The Authors mentioned in line 114 that: "Air sampling was conducted once a month during the dry season (February – April 114 2018) and the rainy season (June – December 2018)".
That is, only nine samples were collected, which is a very small number to build research and approve its results.
2- In line 157: "Therefore, this study assumed that the concentration of NO2 in both indoor and outdoor areas was similar".
This is a wrong scientific assumption, so judging whether the results are similar or different is done by measuring and comparing values, not by assumption.
3- In line 180, Table 2: The values of NO2 were placed in the five study regions, while the rest of the factors were set to one unknown value in any region. The table needs clarification and reconstruction.
4- In line 277: The meteorological conditions that correlated with NO2. It was not clarified whether it is an average for the months of the study or for the days of sampling.
The English Language is good.
Author Response
Thank you very much for a good comment and suggestion. I tried to revise the manuscript as the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
You may use newly references. 38 refernces are not enough.
Author Response
Thank you very much for a good comment and suggestion. I tried to revise the manuscript as below explanation.
You may use new references. 38 references are not enough.
Answer: I added more new references and the total number of references was 46 references, which is enough to support our finding.
Reviewer 3 Report
1. In introduction section, please shorten the first paragraph regarding your background information and significance of the study.
2. In introduction section, 2nd paragraph, the research gaps are not clearly presented. Extensive rewriting is advised. For instance, "Many researchers have studied the influence of parameters including sources, meteorological factors, and land properties on pollutant accumulation in the study areas. They studied the different parameters separately" is not a clear way to present research gap.
3. The research aims and objectives are advised to present as a single paragraph in the introduction section.
4. In methods section, did the authors consider grid cells of other sizes, for instance 1000 m by 1000 m, as an alternative sensitivity finding?
5. It is unclear how the authors conducted the "Health risk assessment". What kinds of health conditions were considered in their study? What are "adverse health effects", mortality or morbidity or disease burden of some types of diseases?
6. Health hazards are generally evaluated by the Cox regression, based on the cohort design, or by the logistic regression, based on the case-control design, or by the meta regression, similar to the comparative risk assessment conducted by WHO and GBD study. The current study seems to match with none of those.
7. The correlation test is generally used as a means to rule out collinearity before actual regression. Dicussion and main interpretation only using the findings from the correlation test may not be sufficient (page 10 of 12, 294-298). Authors should consider more advanced regression modeling to reach the conclusion on "traffic emissions were high area of high road density and related to the pollutant concentration". Correlation test is not generally acceptable, since its incapability of controling the confounders.
8. The English writing is poor, extensive modification is advised. For instance, "traffic emissions were high area" (page 10 of 12, 294-298). Another instance, "The In general, air pollution in urban areas is increasing over time" (page 1 of 12, 35-36).
The English writing is poor, extensive modification is advised. For instance, "traffic emissions were high area" (page 10 of 12, 294-298). Another instance, "The In general, air pollution in urban areas is increasing over time" (page 1 of 12, 35-36).
Author Response
Thank you very much for a good comment and suggestion. I tried to revise the manuscript as the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
This paper deals with the NO2 concentration and some climatic elements. However, there are many unclear parts of this paper (besides some minor points written in the manuscript). The main question is that Air pollution is very well correlated with some climatic elements (especially winds and the height of the PBL) and those points are not addressed. Also, the 2 seasons (summer and rainy) must be clarify as well as how the measurements were collected (it was once in a month but the meteorological conditions are the same?! What about the weakday (or weekend), etc
Comments for author File: Comments.pdf
Author Response
Thank you very much for a good comment and suggestion. I tried to revise the manuscript as an attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Good work, best regards.
Author Response
Thank you very much for your very good suggestions.
Reviewer 3 Report
1. In the “Health risk assessment" section, even though the authors stated the EPA method for health assessment, whether this method can be applied to the Thailand population remains a question. I understand that, some parameters of the method have been extracted from prior study conducted in Thailand, which is good, but how valid and reliable those parameters are. Authors may provide some sort of sensitivity analysis and provide a confidence interval or uncertainty interval, along with their point estimates in the table.
2. This paper does add merits to the field of "Health risk assessment", yet I have concern for the correlation analysis section. The findings may only be regarded as preliminary, as you cannot rule out the confounders using only Spearman correlation. You may need to discuss about it, if no further regression analysis is performed.
3. Furthermore, it would be interesting to see if any nonlinear relationship between NO2 and your variables of interest exists. You may need to disucss about this particular issues in the limitation section of the paper, if you don't use any regression methods.
Languages have been improved, but more can be considered. Considering the overall length of the paper, I do think it can be shorter.
Author Response
Thank you very much for a good comment and suggestion. I tried to revise the manuscript as an attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
the authors did most of my comments/suggestions.
Author Response
Thank you very much for your very good suggestions.
