Plastic Waste Management Practices in Zanzibar’s Coastal Tourist Communities

Round 1

Reviewer 1 Report (New Reviewer)

Comments and Suggestions for Authors

This paper examines plastic waste management practices in coastal tourist communities in Zanzibar, addressing a topic of significant practical and academic relevance. The study employs a qualitative approach, combining case studies and descriptive surveys to provide a comprehensive understanding of local challenges and strategies. The structure of the paper is well-organized, and the data collection methods are diverse. However, several areas require further improvement.

(1) In Zanzibar, tourism is not only an economic pillar but also a vital lifeline, contributing around 28% to the island’s GDP and 82% to its foreign exchange earnings [8,9].” “Tourism-related waste in Zanzibar averages 1.5–2 kg per tourist per day, which is three to four times higher than the local waste generation rate [17]. These values may change over time. Therefore, please specify the time period for these data to enhance reliability.

(2) This study investigates innovative and context-specific approaches for managing plastic waste in Zanzibar’s rapidly expanding tourism sector, with the goal of aligning local practices with global sustainability frameworks. The study's innovative contributions require clearer articulation, which can be demonstrated through explicit comparisons with existing literature.

(3) Structured interviews were conducted using predefined guides to explore community involvement in plastic waste management, types of waste generated, current practices, and challenges. What was the sample size for these interviews? When were the interviews conducted? Were predetermined question items used? What specific content did the interview guides cover? The authors need to provide more detailed information about the interview process.

(4) The study was conducted in the northern and southern districts of Unguja Island, Zanzibar, in the high-tourism areas of Kendwa, Nungwi, Paje, and Michamvi. The research design section should provide more detailed justification for the selection of these five specific areas as study sites, including supplementary quantitative indicators for the selection criteria.

(5) The study predominantly involved female participants, with 95% of interviewees and 75% of workshop participants being women. The authors need to clarify whether the male sample size is sufficient and representative.

(6) The discussion would benefit from incorporating comparative analysis with existing literature to contextualize whether the findings confirm, contradict, or expand upon prior research outcomes in this field.

(6) While the study provides valuable insights into plastic waste management in Zanzibar's coastal communities, the discussion would benefit from explicitly addressing the potential transferability of these findings to other regions with similar tourism-dependent economies.

(7) The authors need to supplement more recent and relevant literature. Some recommended readings include: 1) Environmental Impact Assessment Review-2024-Exploring paths underpinning the implementation of municipal waste sorting: Evidence from China. 2) Journal of Environmental Planning and Management-2024-The power of biojustice environmentalism in the Global South: insights from the politics of reducing single-use plastics in Guatemala. As a general guideline, literature published within the last three years (2023–2025) should constitute no less than 30% of the total references.

(8) The authors are advised to provide a more detailed discussion of the study's limitations, particularly regarding the impact of research duration and seasonal variations. In addition, the authors should add a dedicated "Future Research Directions" section to outline unresolved questions and provide actionable guidance for subsequent studies.

(9) Standardize the reference citation format throughout the manuscript. Additionally, the authors should conduct a comprehensive review of the document's formatting and language usage.

Author Response

Reviewer Comments and Author Responses

(1) “In Zanzibar, tourism is not only an economic pillar but also a vital lifeline, contributing around 28% to the island’s GDP and 82% to its foreign exchange earnings [8,9]. Tourism-related waste in Zanzibar averages 1.5–2 kg per tourist per day, which is three to four times higher than the local waste generation rate [17]. These values may change over time. Therefore, please specify the time period for these data to enhance reliability.”

Response:

We thank the reviewer for this valuable comment. The time period for the cited data has been specified to enhance accuracy and reliability. The revisions are highlighted on page 2, lines 85–87.

(2) “The study's innovative contributions require clearer articulation, which can be demonstrated through explicit comparisons with existing literature.”

Response:

We appreciate this insightful suggestion. We have strengthened the articulation of the study’s innovative aspects by explicitly comparing our findings with relevant existing literature. These revisions are presented on pages 3–4, lines 142–155.

(3) “Structured interviews were conducted using predefined guides… The authors need to provide more detailed information about the interview process.”

Response:

Thank you for this important suggestion. We have expanded the description of the interview process to include the sample size, interview period, use of predetermined question items, and specific content of the interview guide. These details are now included on page 5, lines 213–220.

(4) “The research design section should provide more detailed justification for the selection of these five specific areas as study sites, including supplementary quantitative indicators for the selection criteria.”

Response:

We thank the reviewer for the helpful observation. We have provided a clearer justification for selecting the five study sites, supported by quantitative indicators related to tourism intensity and waste generation levels. The revision is found on page 4, lines 195–197.

(5) “The study predominantly involved female participants… The authors need to clarify whether the male sample size is sufficient and representative.”

Response:

We appreciate this observation. We have clarified the representativeness of the male participants and explained the gender distribution rationale in the study. This has been added on page 8, lines 256–262.

(6) “The discussion would benefit from incorporating comparative analysis with existing literature.”

Response:

We agree with this valuable recommendation. Comparative analysis has been incorporated throughout the discussion to contextualize the findings with prior studies. Relevant revisions are on page 17, lines 600–603; page 18, lines 610–618, 628–633, 641–645; and page 19, lines 657–662.

(6) “The discussion should explicitly address the potential transferability of findings to other regions with similar tourism-dependent economies.”

Response:

We thank the reviewer for this constructive comment. We have discussed the potential applicability of our findings to other tourism-based coastal regions. The revisions are highlighted on page 17, lines 600–603, and page 18, lines 616–618.

(7) “The authors are advised to provide more recent and relevant literature... literature published within the last three years (2023–2025) should constitute no less than 30% of the total references.”

Response:

We appreciate this recommendation. We have updated and expanded the reference list to include recent literature from 2023–2025, including the recommended sources. The updated references are 13, 17, 27, 30, 31, 32, 33, 35, 36, 37, 38, 39, 40, 41, etc., making them more than 50% of the total references.

(8) “The authors should discuss the study's limitations and add a ‘Future Research Directions’ section.”

Response:

Thank you for this insightful suggestion. We have added a detailed discussion of the study’s limitations, particularly regarding research duration and seasonal variations, and introduced a new section titled ‘Future Research Directions’ outlining key areas for future investigation. These revisions are located on page 20, lines 729–738, and page 21, lines 740–746.

(9) “Standardize the reference citation format and review formatting and language usage.”

Response:

We appreciate this note. The reference style, formatting, and language have been standardized accordingly.

Reviewer 2 Report (Previous Reviewer 3)

Comments and Suggestions for Authors

The authors have provided a comprehensive overview of the waste disposal situation through surveys they carried out, and present opportunities and challenges to remediate the situation. While the article contains much useful and interesting information, the writing in many areas is substandard and needs improvement prior to publication. The following are some examples, there are many more throughout the article.

 

Singular vs plural word corrections needed: L21, 29,36,37,51,67,73,74,430

Punctuation changes needed: L37,49,411,414,436

Word corrections needed: L70,73,79-80,147,164,395,452,489,597,685

Revision needed:

L157-160 repeats L160-163

L322 “and end up being dumped” is out of place here

L338 explain ‘nearby points’

L347 ‘frustrated by long distances’ is not an appropriate excuse for dumping waste, this is the authors not stating this is illegal (presumably)

L348 what is inadequate logical support when a company is paid to transport waste from point A to point B

L357-358 suggested revision “yet they often negotiate to reduce these fees such that they do not cover the cost of transport and disposal, which results in waste collection companies dumping waste.”

 L514 need to define waste banks here

L537 suggested revision: “activities: waste collection,….”

L650 I believe an underlying cause of waste dumping is that fees are inadequate to cover the costs of the companies that are contracted to transport and dispose of it. If this is the case, the authors should clearly state this

Comments on the Quality of English Language

In general the manuscript is well written, but there are many areas throughout the article that need grammatical corrections. Examples are noted in my comments. 

Author Response

L347 ‘frustrated by long distances’ is not an appropriate excuse for dumping waste, this is the authors not stating this is illegal (presumably).

Thank you for bringing attention to this....We have clarified this on page 10 lines 322-328.

L357-358 suggested revision “yet they often negotiate to reduce these fees such that they do not cover the cost of transport and disposal, which results in waste collection companies dumping waste.”

Thank you for pointing this out....This has been corrected on page 10: lines 324-328.

 L514 need to define waste banks here…Waste banks have been defined on page 15, lines 516-521.

L650 I believe an underlying cause of waste dumping is that fees are inadequate to cover the costs of the companies that are contracted to transport and dispose of it. If this is the case, the authors should clearly state this

Thank you for pointing this out…We have therefore stated this clearly at pg 10; ln 337-350.

In general the manuscript is well written, but there are many areas throughout the article that need grammatical corrections. Examples are noted in my comments.

Thank you for the reviewer’s careful attention to the language and formatting of the manuscript. All suggested grammatical, punctuation, and stylistic corrections have been fully addressed. Singular and plural forms have been standardized, punctuation adjusted for clarity, and several instances of word choice refined to ensure precision and consistency throughout the text. Redundant sentences have been removed to enhance readability and flow.

Finally, the entire manuscript has undergone comprehensive review and formatting by a professional English-language editing service to ensure grammatical accuracy and overall publication readiness.

Round 2

Reviewer 1 Report (New Reviewer)

Comments and Suggestions for Authors

 Accept in present form

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

very comprehensive and nicely made paper

it is important that plastic waste is taken seriously also in Africa cases more and more.

Introduction with referencing and state of the art review is well done

methodology aspects and structuring of description might be improved, but is well done in general

Figures good

more frontier outlook would be recommended in conclusive part how in practice we can mitigate the problems and improve some action plan

there was a Horizon project about tourist waste in metropolitan areas. Suggest to look for referencing, the name was UrbanWaste

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions.

Methodology aspects and structuring of description might be improved, but is well done in general

We  have improve the methodology aspect by enhancing the structure and provide more clarity and addressing methodological gaps

Figures good

More frontier outlook would be recommended in conclusive part how in practice we can mitigate the problems and improve some action plan

We have extended the conclusion to provide more comprehensive outlook on practical solutions for mitigating plastic waste particularly focusing on actionable strategies for Africa and Island communities. page  (14 ) line (539-580)  

 

There was a Horizon project about tourist waste in metropolitan areas. Suggest to look for referencing, the name was Urban-waste

We have in cooperate additional frontier research and provide more  detailed discussions on the plastics waste situation, particularly in African contexts.

We have expanded the literature reviews with more references especially in relevant more project such as urban waste and other study on plastic waste management in metropolitan or island communities. page no. 2 (line 65- 67), page 7 line (70-85, 82-85)

Reviewer 2 Report

Comments and Suggestions for Authors

Although the authors study an important topic for environmental sustainability, I think the documents look like a report and lacks scientific soundness to be considered for publication. Among other aspects, the literature review, a financial and statistical analysis should be developed.

Author Response

Please see attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

This is a well written article that describes much-needed research that helps to elucidate the plastic waste situation that is plaguing island communities worldwide.

Included in the article is red text that shows some changes I suggest. Also included are comments for the authors to suggest clarifying information they present. Below are general comments for author's consideration and potential for article revision. 

 Aren't the contractors paid by hotels to pick up the waste? Are the authors saying they are not being paid adequately to cover the cost of transporting the waste to the dump or the official places where it is supposed to go? Or are the companies simply not fulfilling their end of the bargain?

 I believe the authors found that some contractors who are paid to take waste to an official dumpsite are instead dumping it illegally. If this is the case, the authors should consider stating this more clearly and objectively in the article. It is understandable that it can be difficult to call out such wrong doing, but the goal of research is to provide an honest and impartial view of a situation.

 How does trash/plastic separation help when there is no industry present to recycle the plastic waste? If it is all being dumped in a landfill, why is it necessary to sort? Further, information provided indicates that even when waste is sorted, the companies that pick it up are just dumping it randomly in nature. The waste is not making it to the official dump sites. If this is the case, how will sorting help?

 The authors cite other studies to support their case, please state where these studies were carried out. In Zanzibar?

 

At the end of the the article, the authors include a sentence regarding what is needed for sustainable plastic waste management: “training community members to produce plastic bricks, and pavements for road construction and explore other feasible emerging innovations” This provides a real potential solution for plastic recycling – the authors should provide a few more details or examples of how and where this is being done.

Reducing the use of plastics and what is needed to establish meaningful plastic recycling on Zanzibar should be included throughout the article. These are both key points that have a potential to help solve the problem of plastic waste.

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions.

This is a well written article that describes much-needed research that helps to elucidate the plastic waste situation that is plaguing island communities worldwide.

Included in the article is red text that shows some changes I suggest. Also included are comments for the authors to suggest clarifying information they present. Below are general comments for author's consideration and potential for article revision.

Aren't the contractors paid by hotels to pick up the waste? Are the authors saying they are not being paid adequately to cover the cost of transporting the waste to the dump or the official places where it is supposed to go? Or are the companies simply not fulfilling their end of the bargain?

The situation regarding contractors have be clarified and reasons for, illegal for dumping has be clarified. Page no. (8 ) line no ( 304-312)  

I believe the authors found that some contractors who are paid to take waste to an official dumpsite are instead dumping it illegally. If this is the case, the authors should consider stating this more clearly and objectively in the article. It is understandable that it can be difficult to call out such wrong doing, but the goal of research is to provide an honest and impartial view of a situation.

The issues of contractors who are paid to take waste to an official dumpsite but dumping it illegally has been clarified. page no (8 ) line no ( 304-312)  

How does trash/plastic separation help when there is no industry present to recycle the plastic waste? If it is all being dumped in a landfill, why is it necessary to sort? Further, information provided indicates that even when waste is sorted, the companies that pick it up are just dumping it randomly in nature. The waste is not making it to the official dump sites. If this is the case, how will sorting help?

The issue of how sorting help despite the absence of industry to recycle waste has been elaborated page no ( 11) line no (414-418 )  

 The authors cite other studies to support their case, please state where these studies were carried out. In Zanzibar?

At the end of the the article, the authors include a sentence regarding what is needed for sustainable plastic waste management: “training community members to produce plastic bricks, and pavements for road construction and explore other feasible emerging innovations” This provides a real potential solution for plastic recycling – the authors should provide a few more details or examples of how and where this is being done.

Potential solutions and example solution for plastic recycling provided. Page no (14 ) line no (539-580)  

 Reducing the use of plastics and what is needed to establish meaningful plastic recycling on Zanzibar should be included throughout the article. These are both key points that have a potential to help solve the problem of plastic waste.

Included thoroughly in various parts of the paper. 

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

In my oppinion, the authors did not match my previous comments about the paper. Thus, I remain my oppinin about the absence of quality to be considered for publication.