Accumulation and Toxicity of Polycyclic Aromatic Hydrocarbons in Long-Term Soil Irrigated with Treated Wastewater
, Faruq Mohammad 2, Hamad A. Al-Lohedan 2 and Ahmed A. Soleiman 3
Round 1
Reviewer 1 Report
The study presents the impact of treated wastewater irrigation (TWWI) on agricultural soils in water-poor regions, with particular emphasis on the presence and accumulation of polycyclic aromatic hydrocarbons (PAHs). This is an important topic due to the potential ecotoxicological threat to the environment. The research was well planned, the results well presented and the work may be of interest to readers. However, the reviewer points out minor corrections that will improve the quality of the article:
· Lines 11-12 replace „This issue is particularly significant due to the potential threats it poses to environmental security.” With This issue is particularly significant due to its potential threats to environmental security.
· Introduction: Please emphasize that sewage irrigation only occurs in countries with limited water resources. The chemical composition of wastewater is also important, as it can affect the contamination of wastewater, hence the authors conducted their research.
· 2.2. Sampling and pre-treatment : in the reviewer's opinion, it would be better to collect soil samples from a depth of 0-20 cm in future research.
· Figures 1-7.: improve the quality of figures.
· Figure 2 - put error bars on the graph..
· Figure 7 - put error bars on the graph
· Conclusion: what are the future research plans regarding the issues presented by the authors?
Comments for author File: 
Comments.pdf
Minor editing of English language required.
Author Response
Manuscript ID: sustainability-2528135
Title: Accumulation and toxicity of polycyclic aromatic hydrocarbons in long-term soil irrigated with treated wastewater
Reviewer#1 :
The study presents the impact of treated wastewater irrigation (TWWI) on agricultural soils in water-poor regions, with particular emphasis on the presence and accumulation of polycyclic aromatic hydrocarbons (PAHs). This is an important topic due to the potential ecotoxicological threat to the environment. The research was well planned, the results well-presented and the work may be of interest to readers. However, the reviewer points out minor corrections that will improve the quality of the article:
Reply: Response: Thank you for taking the time to review our manuscript and for your positive evaluation of our work. We appreciate your efforts in providing us with constructive feedback. We have carefully considered your comments and revised the manuscript accordingly.
Please find our responses to your specific comments below:
- Lines 11-12 replace „This issue is particularly significant due to the potential threats it poses to environmental security.” With This issue is particularly significant due to its potential threats to environmental security.
Reply: We agree with your comments. Lines 11-12 have been replaced as per your suggestion.
- Introduction: Please emphasize that sewage irrigation only occurs in countries with limited water resources. The chemical composition of wastewater is also important, as it can affect the contamination of wastewater, hence the authors conducted their research.
Reply: As per your wonderful suggestion the raised points have been incorporated into the revised manuscript. “Sewage irrigation is a practice that is predominantly found in countries with limited water resources. This method involves using treated wastewater for irrigation purposes, effectively conserving freshwater reserves. However, it is crucial to consider the chemical composition of the wastewater, as it plays a significant role in determining the level of contamination. The presence of hazardous chemicals and pollutants in wastewater can have detrimental effects on the environment and public health. Therefore, careful monitoring and treatment of wastewater are essential to ensure that the practice of sewage irrigation remains sustainable and environmentally friendly.”
- 2.2. Sampling and pre-treatment: in the reviewer's opinion, it would be better to collect soil samples from a depth of 0-20 cm in future research.
Reply: We will incorporate this suggestion in our future research. Thank you for the valuable feedback.
Figures 1-7.: improve the quality of figures.
Reply: We apologize for any inconvenience caused by the poor visibility of the figure. After receiving your feedback, we have improved the resolution of all Figures
Figure 2 - put error bars on the graph.
Reply: We are grateful for the suggestion. We have reviewed and revised the as per your suggestion and error bars are added in Figure 2.
- Figure 7 - put error bars on the graph
Reply: Thank you for your advice. This is to inform you that Figure -7 was obtained directly from the PMF, so here error bars cannot be introduced. Sorry for the inconvenience.
- Conclusion: what are the future research plans regarding the issues presented by the authors?
Reply: Our future research will primarily focus on the onsite bioremediation of contaminants found in wastewater used for irrigation purposes. With the aim of ensuring sustainable and environmentally friendly sewage irrigation practices, we will explore and develop innovative bioremediation techniques that can effectively remove harmful substances from wastewater. This will involve studying the use of specific microorganisms, plants, or other natural processes that have the potential to degrade or transform contaminants present in the wastewater.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The present article entitled “Accumulation and Toxicity of Polycyclic Aromatic Hydrocarbons in Long-Term Soil Irrigated with Treated Wastewater” is an interesting and updated theme. However the present article needs an extensive revision of English.
-Author should add the stat in the table. 1 and figure 2,
-Author should also mentioned about the replicates in the materials and method section
- Fig .6 text of figure is not visible
Table. 3, If authors have written possible sources , then add here reference or source of information
Check and revise the reference style of paper,
The present article entitled “Accumulation and Toxicity of Polycyclic Aromatic Hydrocarbons in Long-Term Soil Irrigated with Treated Wastewater” is an interesting and updated theme. However the present article needs an extensive revision of English.
-Author should add the stat in the table. 1 and figure 2,
-Author should also mentioned about the replicates in the materials and method section
- Fig .6 text of figure is not visible
Table. 3, If authors have written possible sources , then add here reference or source of information
Check and revise the reference style of paper,
Author Response
Manuscript ID: sustainability-2528135
Title: Accumulation and toxicity of polycyclic aromatic hydrocarbons in long-term soil irrigated with treated wastewater
REVIEWER# 2
The present article entitled “Accumulation and Toxicity of Polycyclic Aromatic Hydrocarbons in Long-Term Soil Irrigated with Treated Wastewater” is an interesting and updated theme. However, the present article needs an extensive revision of English.
Reply: Thank you for your feedback on the article. We appreciate your constructive feedback. We agree that the English language in the article requires extensive revision, we have revised the manuscript accordingly to address English improvement. Your input is valuable, and we will ensure that the revised version meets the highest standards of language proficiency.
- Author should add the stat in the table. 1 and figure 2.
Reply: Thank you for providing the information about the addition of statistics in Table 1 and Figure 2.
Author should also mention about the replicates in the materials and method section
Reply: Thank you for your suggestion. It is indeed important to mention the replicates in the revised manuscript to provide transparency and ensure the reliability of the research findings. The following section has been added to the revised manuscript.
Line no.190-192
“The replicate sample analysis was also performed for each sample. The number of replicates used in the study allows for a better understanding of the statistical analysis and the robustness of the results.”
- Fig .6 text of figure is not visible
Reply: Thank you for bringing this to our attention. We apologize for the inconvenience caused by the text in Figure 6 being not visible. We have addressed this issue in the revised manuscript.
- Table. 3, If authors have written possible sources, then add here reference or source of information
Reply: Thank you for your suggestion regarding Table 3. We have added the references or sources of information for the possible sources mentioned in the table.
- Check and revise the reference style of paper.
Reply: Thank you. We have thoroughly checked and revised the references as per the journal's guidelines.
Author Response File: Author Response.docx
Reviewer 3 Report
The submitted manuscript is well written, clear, concise, nicely presented. The study design is current and amount of new information is appropriate. I recommend acceptance after minor revisions.
Line 15 as „Flur” and „Pye” were not defined previously, this information is meaningless. Either use the full name of those compounds or rewrite this sentence.
Lines 48-50, the names of those compounds should be included, preferable in the form of a table
In the text, there are no reference to Figures 1, 2 and 3, i.e. ref. to figure 1 should appear in Line 100
Table 1, please explain, how it is possible that the sum of % of clay, slit and sand exceeds greatly 100%?
Figure 2, the quality (DPI) must be improved. Also, please add error bars and perform the statistical analysis to compare the different regions.
Figures 3, 4, the quality of those figures MUST be improved
The figure presenting the chemical structures of the find compounds (those of the highest concentrations) should be introduced
Through the manuscript, the authors use term “significantly higher” etc., while they have not performed any statistical analysis of the collected results. Why?
Author Response
Manuscript ID: sustainability-2528135
Title: Accumulation and toxicity of polycyclic aromatic hydrocarbons in long-term soil irrigated with treated wastewater
Reviewer#3 :
The submitted manuscript is well written, clear, concise, nicely presented. The study design is current and amount of new information is appropriate. I recommend acceptance after minor revisions.
Reply: Thank you for your positive feedback on the submitted manuscript. We are glad to hear that the paper is well-written, clear, concise, and nicely presented. We appreciate your assessment of the study design as current and the amount of new information as appropriate. We will carefully address any minor revisions you may have suggested to ensure the manuscript is further improved.
Line 15 as „Flur” and „Pye” were not defined previously, this information is meaningless. Either use the full name of those compounds or rewrite this sentence.
Reply: Thank you for your feedback on line 15 of the manuscript. You are correct that the terms "Flur" and "Pye" were not defined previously. To address this issue, we have used the full names of the compounds (Please refer to line no. 16).
- Lines 48-50, the names of those compounds should be included, preferable in the form of a table
Reply: Thank you for providing the information about the addition of the 16 PAHs in the text (lines 179-183) and Table 2.
- In the text, there are no reference to Figures 1, 2 and 3, i.e. ref. to figure 1 should appear in Line 100
Reply: Thank you for pointing out the missing references to Figures 1, 2, and 3 in the text. l. We have made the necessary revisions accordingly in the revised manuscript.
Table 1, please explain, how it is possible that the sum of % of clay, slit and sand exceeds greatly 100%?
Reply: Thank you for bringing this discrepancy in Table 1 to our attention. It seems there may have been an error in the calculation or reporting of the percentages of clay, silt, and sand. With your query, we have rechecked the values, and the sum of values was found equal to 100%.
- Figure 2, the quality (DPI) must be improved. Also, please add error bars and perform the statistical analysis to compare the different regions.
Reply: Thank you for your valuable input, We have made the necessary improvements to Figure 2 to meet the requirements you have suggested.
- Figures 3, 4, the quality of those figures MUST be improved
Reply: We sincerely apologize for the issues with the quality of these figures. In the revised version of the manuscript, we have improved the image quality to ensure that the figures are clear, and legible.
- The figure presenting the chemical structures of the find compounds (those of the highest concentrations) should be introduced
Reply: We understand that the factor contribution in Figure 7 is obtained directly from the PMF software after performing the required analysis. This analysis helps identify the possible sources contributing to the observed data. Including this information in the figure allows readers to understand the significant factors and their contributions to the overall results. We appreciate your clarification and will ensure that the revised manuscript accurately reflects the source of Figure 7 as obtained from the PMF software analysis. Thank you for your valuable input.
- Through the manuscript, the authors use term “significantly higher” etc., while they have not performed any statistical analysis of the collected results. Why?
Reply: Thank you for clarifying that the statistical calculations were indeed performed and that the term "significantly higher" was used based on the results of these calculations. The inclusion of statistical analysis is crucial for accurately interpreting and reporting research findings. By conducting appropriate statistical tests and determining significant differences, we have ensured the scientific rigor and validity of this.
We apologize for the misunderstanding and any confusion caused. It is essential to clearly state the statistical methods and results in the manuscript to support the use of terms such as "significantly higher." We appreciate your attention to this matter and will ensure that the revised version of the manuscript accurately reflects the statistical analysis performed. Thank you for your diligence in conducting and reporting the statistical calculations.
Author Response File: Author Response.docx
