Case Study of Cancer Incidence in Relation to Diverse Environmental Exposure to PCDD/Fs in the Silesia Province, Poland

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This is a very interesting cross-sectional study. The manuscript explores the relationship between residents' inhalation exposure to PCDD/Fs and PCBs and cancer incidence in three villages in Silesia, where one village has continuous exposure to persistent organic pollutants (POPs).

One of my primary concerns is that human health is often influenced by multiple environmental factors, including water and soil pollution. Therefore, I suggest incorporating an analysis of water and soil contamination, which could lead to more robust scientific conclusions.

Another major comment is that the abstract should be expanded and refined. The current abstract is overly simplistic and lacks a detailed description of the study’s findings. For example, the final sentence (i.e., "A significantly higher cancer incidence was also observed among residents of the case study villages compared to the reference village, with cancers of the digestive system, respiratory and thoracic organs, skin, urinary system, lymphatic and hematopoietic systems, as well as female-specific cancers, being the most prevalent") should include specific results to support these observations.

Additionally, the conclusion section requires further improvement. It should not only summarize the key findings but also offer recommendations on how to address the study’s limitations and propose future research directions.

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study investigates the relationship between cancer incidence and exposure to persistent organic pollutants (POPs) in Silesia Province, Poland. The introduction provides an extensive background on global cancer trends and environmental pollution but lacks a detailed discussion on existing literature and the specific knowledge gap this research aims to address. The paper does not adequately highlight whether similar studies have been conducted in Poland or other regions, and there is insufficient emphasis on the unique context of the Silesia Province, which could justify the need for this study. the article has potential, but it requires substantial revision to clarify the research's relevance, the gap it fills, and why the study of Silesia is particularly valuable.

 

Specific Comments:

1. The structure of Table 1 is confusing and disorganized. Some villages or communes appear to correspond to two different categories, which may cause confusion. I recommend reorganizing the table for clarity, ensuring that each location is accurately represented and the data is easier to interpret.
2. It would be beneficial to add a table summarizing key information about each study site, such as the total population and the population included in the study, gender distribution, age composition, the number of samples excluded due to follow-up issues or data quality concerns, and information about emission sources. This would provide essential background for readers to better understand the study context and its generalizability.
3. My understanding is that villages CY and GN belong to commune KZ, while village KO belongs to commune KC. However, at the village level, the IR follows the trend GN > CY > KO, but at the commune level, the trend reverses to KZ < KC. Could the authors clarify the reason for this inconsistency? If necessary, additional analysis should be provided to address potential confounding factors or to verify the calculations.
4. The discussion on the relationship between exposure dose and cancer response is quite limited. I recommend expanding this section to provide more detailed analysis. For example, while the overall association is significant, the relationship is not significant for women. Are there studies that support this finding? Additionally, the paper aggregates all cancer types into one analysis. It would be beneficial to discuss cancer types separately, as some cancers are more prevalent in females, while others are more common in males.
5. Some statistical analyses, such as those comparing IRs across villages and communes, could be more clearly presented. The inclusion of effect size measures and confidence intervals would strengthen the robustness of the findings. Additionally, the rationale behind selecting specific statistical tests should be explicitly stated to enhance reproducibility.
6. While the study primarily focuses on air pollution exposure, other potential confounding factors such as lifestyle differences, occupational exposures, and genetic predispositions are not discussed in detail. Addressing these aspects, even briefly, would provide a more comprehensive interpretation of the results.
7. Some methodological descriptions, such as the selection criteria for villages and communes and how exposure levels were assessed, could be explained more clearly. A more detailed description of the exposure assessment methods would help strengthen the validity of the study.

Comments on the Quality of English Language

The quality of the English language in this manuscript is generally good, and the overall structure is clear. 

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

This manuscript presents a study on the relationship between environmental exposure to PCDD/Fs and cancer incidence in the Silesia Province, Poland. The research provides valuable insights into the potential impact of air pollution on public health in the region. However, following points need to be clarified in the revised manuscripts before it is considered to be accepted.

 

1. Data Source (Section 2.2): The rationale for selecting three heating seasons (2014/2015, 2021, 2022/2023) is unclear. It is not demonstrated whether these data adequately represent long-term exposure levels (2005–2022 study period). The manuscript should clarify the temporal alignment between air pollutant concentration data and the study duration.

 

2. Confounding Factors: The study does not account for potential confounders (e.g., smoking, diet, occupational exposure), which may compromise causal inference. Multivariate analysis incorporating variables such as age, gender, and smoking rates is recommended.

 

3. Statistical Methods: The justification for selecting statistical tests (e.g., ANOVA, Kruskal-Wallis) is unclear. Inconsistencies between post-hoc tests (e.g., Dunn-Bonferroni vs. Conover) require explanation.

 

4. Incidence Rates (Section 3.2): Table 2 does not explicitly report female/male cancer incidence rates in the total population. Clarification is needed.

 

5. Exposure Variables (Section 3.3): Regression analysis relies solely on 2,3,7,8-TCDD as an exposure variable, neglecting combined effects of other PCDD/Fs or PCBs. It is recommended that the regression model be extended to include total PCDD/Fs, dl-PCBs, or other key contaminants to analyze the effects of mixed exposures.

 

6. Missing Data in Figures: Key figures (e.g., Figure 2) lack specific numerical values and statistical test results.

 

7. Study Limitations: It is recommended that the limitations of the study be clarified in the discussion and future research directions be suggested.

 

8. Ethical compliance: Although the ethical statement states that “no humans or animals are involved”. The use of cancer patient data in the study needs to be reconfirmed to meet ethical review requirements.

 

9. Environmental mitigation strategies: The manuscript should include literature on protective measures against particulate matter and dioxin exposure, such as advanced air filtration technologies (e.g., Advanced Materials, 2020, 32, 2002361; Journal of Membrane Science, 2022, 660, 120857) and nanotechnology-enabled pollutant capture solutions (Journal of Colloid and Interface Science, 2021, 597, 48). These references will strengthen the recommendations for reducing exposure.

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The authors showed in this paper how air pollution may be one of the main reasons for cancer incidence disparities in Poland compared to other European countries. This study examined three villages in Silesia, with one chronically exposed to persistent organic pollutants (POPs). A significant link was found between long-term inhalation of 2,3,7,8-TCDD and increased cancer incidence, particularly among men and the general population. Residents of the exposed village showed significantly higher rates of cancer, especially of the digestive, respiratory, skin, urinary, lymphatic, hematopoietic systems, and female-specific cancers, compared to the reference village.

 

• lines 27/28 - keywords - to enhance the visibility of your article in search results, consider revising the keywords to eliminate any repetition from the title. This approach can help attract a broader audience and improve your content's searchability.
• line 116 - please eliminate the bullet point at the beginning of the sentence. Bulleted lists should only be utilized for enumerating items. Additionally, ensure that a full stop is placed at the end of the final bullet point.
• line 141 - please ensure that a full stop is placed at the end of the final bullet point
• line 195 - please rewrite R2 as R²
• figures 1-12- a constructive suggestion: it might be beneficial to retain the graphs in the figures while also creating separate summary tables for the results of the ANOVA and post-hoc tests (Figures 1–3), the Mann-Whitney test (Figures 4–6), and the Kruskal-Wallis and post-hoc tests (Figures 7–12). This approach could enhance clarity for your readers.
• Additionally, consider referring to the figures and tables from the results section in the discussion to strengthen your analysis.

Author Response

"Please see the attachment."

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

No more comments.

Author Response

Thank you very much for accepting our corrections.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have revised the manuscript based on the reviewers' suggestions and the manuscript is now ready for publication.

Author Response

Thank you very much for accepting our corrections.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Authors,
Thank you for thoughtfully addressing the suggestions provided. Your efforts in enhancing the quality of your article are commendable.

• lines 31/32 - keywords - still the content appears to be repeating phrases already present in the title: Silesia Province and Poland
• line 145 - it appears that a reference is missing, as it only mentions "XYZ, 2023." Would it be possible to provide the complete citation?
• lines 142-162 - could you please indicate where you refer to Table 1 within the text?
• line 168 - please rewrite 10th into 10^th 
• figures 1-13 - please ensure that the style, font, and size of letters and numbers used in figures and their corresponding tables are consistent with those utilized throughout the entire article. This consistency is important for maintaining the document’s professionalism and clarity.
• In the discussion section, your analysis of the results was insightful; however, it would be beneficial to reference the figures and tables from the results section. Doing so could enhance the clarity and robustness of your analysis. e.g. The villages constituting the study areas (CY and GN) belong to the KZ commune, while the KO village (reference area) belongs to the KC commune (Table 1). or Furthermore, analysis of the incidence of individual cancer groups also showed significantly higher rates of digestive system (figure 7), respiratory system (figure 8) and urinary system cancer (figure 11) in the population living in the studied villages (CY or GN) compared to the reference village (KO). etc.
• lines 489-499 - the areas discussed in the text are related to research conducted in Italy. It is recommended to avoid referring directly to terms such as “Zone 1,” “Zone 2,” and “Zone 3.” Instead, it may be more effective to describe these regions in a contextual manner, such as identifying the area that is farthest from the accident epicenter, etc. Using specific zone references that are not defined within the scope of your study may lead to confusion for the audience. Therefore, employing descriptive comparisons when presenting your findings is advisable to enhance clarity and understanding.                                                                                                                                 

Author Response

Dear Reviewer,

We are grateful for your favourable evaluation of our efforts to enhance the article. We are also grateful for your further corrections, which will certainly further refine our manuscript and improve its quality. All changes made are underlined in yellow in the manuscript text. In pdf. file are some explanations on your comments.

Regards, Authors

Author Response File: Author Response.docx