PONE-D-24-49990Human Health Risk Assessment of Arsenic and Potentially Toxic Elements Exposure in Bread and Wheat Flour in Northeast IranPLOS ONE

Dear Dr. Tavakoly Sany,

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Academic Editor

PLOS ONE

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Additional Editor Comments :

1. Strengthen the conclusion by briefly mentioning policy recommendations and necessary interventions.

2. Reduce redundancy in explaining the significance of bread as a staple food.

3. Justify why Mashhad was chosen for this study beyond high bread consumption.

4. Provide a stronger connection between previous studies and the novelty of this research.

5. Explain whether age groups were classified based on local dietary habits.

6. Ensure consistency in reporting p-values and statistical significance.

7. Address why Pb and Hg were below detection limits—were any confirmatory analyses conducted?

8. In Figure 2, highlight which metals exceeded WHO/FAO limits more clearly.

9. Provide a more detailed breakdown of which elements contributed most to the Hazard Index (HI).

10. Discuss whether variations in risk assessment values between adults and children were statistically significant.

11. Compare findings with existing studies on heavy metal contamination in bread or similar food products.

12. Provide a clearer explanation of why certain metals (Al, As, Cr, Fe) exceeded limits.

13. Discuss whether interventions such as fortification, alternative baking methods, or improved flour processing could reduce contamination.

14. Consider mentioning regulatory limits in Iran compared to international standards.

15. Ensure all figures are labeled correctly, and significance values are consistently included in tables.

16. Correct grammatical issues, including verb tense consistency and article usage.

17. Standardize citation formatting—some references are incomplete.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: No

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: No

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The manuscript presents “Human Health Risk Assessment of Arsenic and Potentially Toxic Elements Exposure in Bread and Wheat Flour in Northeast Iran,” which is noteworthy. The subject addressed is within the scope of the journal but is based on limited and incomplete regional studies. The use of the EPA 3050B method, which is designed only for the acid digestion of sediments, sludges, and soils, is not appropriate for bread and wheat flour. Therefore, the accuracy of the data is fundamentally questionable.

Introduction- What is the novelty of the study? I could not find any significance of this work

Methodology—Sample digestion Method was not appropriate. The selection of an appropriate method for sample digestion is a critical preliminary step to ensure the acquisition of authentic and reliable results. This step is especially important as it directly influences the accuracy, precision, and reproducibility of the subsequent analytical processes.

QA/QC- This section is insufficiently reported. No specified the SRM/CRM number/name. The major drawback of this section is lack of QA/QC data, like, percentage recovery and use of SRM/CRM. The authors must provide the QA/QC data in a Table either in the manuscript or in the supplementary material.

Presentation of Results: This section was extremely poor. The standard permissible limits of heavy metals were not clearly mentioned. Statistical analysis and source identification, both of which are crucial for this type of popular research, were completely ignored in this manuscript.

Overall, the data authenticity, interpretation, QA/QC, sample location description, source identification, and referencing are not satisfactory for publication in the journal PLOS ONE.

Reviewer #2: Comments to the Authors

The manuscript requires significant revisions, particularly in improving the discussion section, clarifying methodological details, and refining the language. The introduction lacks a comprehensive discussion on the various sources of heavy metal contamination in flour and bread. There is no explanation of how individual ingredients such as salt, yeast, and other food additives contribute to increased heavy metal levels in bread. This should be addressed to provide a more complete picture of contamination sources. The discussion section lacks objectivity and, in some parts, is written in a manner similar to the introduction, the section only report the others finding. The authors should ensure that the discussion is based on their results rather than opinions.

Line 33: The verb "employing" is not appropriate for describing methods. Replace it with "applying."

Line 46: Choose more precise and relevant keywords.

Line 69: Avoid repeating "World Health Organization"; use the acronym "WHO" after it has been defined once.

Line 104: What is the per capita bread consumption in Mashhad? What types of bread are commonly produced in the city? The introduction states that "contamination with heavy metals occurs during the preparation and processing of bread." The authors should explain the different processes used in bread production in Mashhad.

Line 107: The authors discuss industrial growth around Mashhad and its potential impact on agricultural contamination. However, they should clarify what percentage of the wheat or flour used in the city is locally sourced.

Line 111: Were samples taken from only one type of flour? Did authors consider the effect of different types of flour in heavy metal levels? Were different types of bread also considered? The results mention multiple bread types, but the materials and methods section lacks clarity regarding this. The authors should explicitly state the types of bread and the different baking processes used, including oven types.

Line 168 & Line 188: All parameters in the formulas should be defined clearly, one by one.

Table 1: Ensure that this table is properly referenced in the text.

Line 224: It is useful to recognize heavy metals whose levels exceed the average. However, this should be clearly stated and discussed in relation to the findings presented in the table.

Line 254: What types of ovens were considered, and how do they influence heavy metal levels? Were formulation effects also considered? It need to be clearly explained

Figure 2 & Table 2: Data should not be duplicated. The authors should either remove Table 2 or Figure 2 to avoid redundancy.

Line 278: Replace "(See table S2)" with "(Table S2)".

Lines 334–338: Some sentences are unclear and need to be rewritten for better readability.

Line 374: Specify the types of ovens used and which had the most significant effect on heavy metal accumulation and why (Explain the mechanisms behind these effects).

Line 375: The reference should be cited as "Alidadi et al." instead of "Zarif et al."

Line 380: The authors should clarify whether they found any correlation between their findings and those of Alidadi et al.

Line 388: Was the effect of water quality on heavy metal levels in bread considered? If not, why was this factor excluded?

Line 425: Does wheat variety affect heavy metal accumulation? If so, this should be discussed.

Lines 427–453: The references provided seem to be a general report rather than a structured conclusion. The authors should clarify whether they are using these references to support their findings or simply listing them without purpose.

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Reviewer #1: No

Reviewer #2: No

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Attachments

Attachment

Submitted filename: Reviewer comments-23-11-2024.docx

Human Health Risk Assessment of Arsenic and Potentially Toxic Elements Exposure in Bread and Wheat Flour in Northeast Iran

PONE-D-24-49990R1

Dear Dr. Tavakoly Sany,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Karthikeyan Venkatachalam, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #3: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Please check one more time of the values of As. Why As is too much and what is the possible sources?

Reviewer #3: The authors have adequately addressed all the comments and suggestions provided by the reviewers. No further revisions are required.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .

Reviewer #1: Yes:  Dr Md Kamal Hossain

Reviewer #3: No

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