Analysis of Pollen Concentrations from Various Tree Pollen Types and Their Interrelation with Different Airborne Pollutants in the Madrid Region (Spain)

Round 1

Reviewer 1 Report

First, I thank the authors and editor for the opportunity to read this interesting work. The authors analyzed the correlation between pollen types and airborne pollutants in the paper and compared their results with two time periods. The manuscript is well-written. However, the methods section can be improved significantly. Thus, the article needs to be revised and edited before publication.

Comments:

1. The result has been driven based on 2013-2017, which is relatively old data. So, how the author(s) compensate or can assert the relevancy of the study in the present day? Please try to address it.
2. Please justify each of the tools used in the data analysis. For instance, why Statgraphics Centurion 18 was used to calculate the degree of correlation?
3. The conclusion part can be well-written.

Specific comments:

1. I would suggest deleting “and objectives” from the introduction section. Also, the study has a single objective, but “objectives” is a plural term.
2. Line 83-87 and 91-93: Citation required.
3. Line 248-251: Missing parenthesis
4. Line 259, “left-hand column of Table 2,” can be rewritten with a clear indication of the table. These types of sentences should be well written so that audience can easily understand them.
5. Tables 2 & 4: I would encourage changing the font color (red to black; white to black). Also, the value can be represented by symbols or characters in the footnote rather than using different font colors.
6. Line 380: This is a hanging sentence and can be merged or added in either of the paragraphs.
7. I suggest splitting the “Discussion and Conclusions” section. It makes the paper clear and more understandable to the audience.
8. The opening sentence of the discussion section is not appropriate. “It can be concluded that…………. “ this can be concluding remarks!

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The article entitled “Analysis of pollen concentrations from various tree pollen types and their interrelation with different airborne pollutants” focuses on presenting statistical correlations between the pollen number for various pollen types and the levels of atmospheric air pollutants in corresponding areas. The study could provide an understanding positive and negative roles of the trees in air purification. The results show some significant relationships but no scientific explanation for such relationships. The negative correlation between PM and pollen number is also questionable and needs explanation. Furthermore, the article fails to provide details on how the samples were collected and analyzed, which should affect the reliability of the results. The following suggestions should be considered to bring academic benefit to broad audiences.

1. Introduction: The authors mention that “air pollution plays an important role in increasing pollinosis.” These could be beneficial? The authors should provide more explanations concerning how air pollution and pollen have interconnected. The following literature should be worth citing.

Sedghy, F., Varasteh, A. R., Sankian, M., & Moghadam, M. (2018). Interaction Between Air Pollutants and Pollen Grains: The Role on the Rising Trend in Allergy. Reports of biochemistry & molecular biology, 6(2), 219–224.

A, Bédard; J, Bousquet; J, Antó; J, Garcia-Aymerich; S, Arnavielhe; D, Laune; M, Sofiev; X, Basagaña Interaction between air pollution and pollen seasons on allergic rhinitis control, Environmental Epidemiology: October 2019 - Volume 3 - Issue - p 26, doi: 10.1097/01.EE9.0000605904.21338.7b

2. Methodology:
   • P4 Line 111-118; the statements are not consistent with those in Table 1. Please correct.
   • List all the six pollen types considered in this study and detail how to sample and analyze the numbers of pollens. Also pictures (with scale) of the pollens are encouraging to depict their allergic potential.
   • Provide information on sampling period, frequency. Please ensure that both pollen and air pollution were sampled concurringly.
3. Result and Discussion
   • Table 2: Explain %PT
   • Table 3: Explain sources of threshold values. The RD102/2011, or 28 January, --- is unknown to broad audiences.
   • Not only providing the correlation but also discussing the interaction between the air pollution and pollen. Intensive reviews must be provided.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The second revision does not much respond to the key concerns.

1. The authors neglected to provide detail on sampling and sample analysis. The authors only mentioned that the samplings were via a volumetric collector and automatic sampling. The authors also mentioned that the sample analysis is by an expert. This information is too brief and lacks of necessary details, such as specific collecting principles/techniques, sampling flowrate, filter type, etc.
2. Discussion on the interconnection between air pollution and pollen is weak and does not provide values for further development. The public aims to gain more understanding of the interconnections in scientific implications (why), not just delivering the results (what and how much).

Author Response

1. The authors neglected to provide detail on sampling and sample analysis. The authors only mentioned that the samplings were via a volumetric collector and automatic sampling. The authors also mentioned that the sample analysis is by an expert. This information is too brief and lacks of necessary details, such as specific collecting principles/techniques, sampling flowrate, filter type, etc.

Response:

Specific information on the sampling that is carried out institutionally by the community of Madrid has been added. Lines 232-251

2. Discussion on the interconnection between air pollution and pollen is weak and does not provide values for further development. The public aims to gain more understanding of the interconnections in scientific implications (why), not just delivering the results (what and how much).

Response:

The interest in the relationship between contaminants and pollen concentration makes sense because of its way of acting on human health. These aspects have been addressed in the discussion, although more research is needed to justify the association of the variables.

To the authors' current knowledge, only two recent papers using similar analyzes have been published.

Ravindra, K., Goyal, A., & Mor, S. (2022). Influence of meteorological parameters and air pollutants on the airborne pollen of city Chandigarh, India. Science of The Total Environment, 818, 151829.

Cariñanos, P., Foyo-Moreno, I., Alados, I., Guerrero-Rascado, J. L., Ruiz-Peñuela, S., Titos, G., ... & de la Guardia, C. D. (2021). Bioaerosols in urban environments: Trends and interactions with pollutants and meteorological variables based on quasi-climatological series. Journal of Environmental Management, 282, 111963.

The conclusions of these works are also like ours, although places and pollen species differ. The correlations found are described but have not been explained. The importance of these results, in themselves, for the study of air quality and health is highlighted.

The fact that the increase in pollutants occurs at the same time as the increase in pollen concentration or its decrease is of interest from the point of view of environmental monitoring and preventive health measures.