Leveraging Life Cycle Assessment and System Dynamics Model Analysis for an Integrated Household E-Waste Management System in Yaoundé, Cameroon
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe topic of the paper is interesting, of public and environmental interest. the material are reasonable as a case study of Yaounde, Cameroon. It is worth publishing after incorporating the following suggestions.
1. Line 21, the sentence starting with policy 1...... is not clear.
2. What is difference between contents of Table 1 and 2? Merge them as they are the same.
3. Line 175-6, insert the "degree" properly from symbols and merge the short sentence "Figure 2...............study area". Also check the entire text for too short sentences and act accordingly.
4. Several sentences start with citation of Figure of Table, revise them.
5. Modify Table 4 such as, use only abbreviations in the Table like LHA-C and include its full form in the footnote of the Table. It will make the Table simple, easy to read and will avoid repetition. My same comment is applied to all other tables.
6. In Table 4, the quantities in 202 were very high, what is its reason? This must be justified with full proofs.
7. Enhance resolution of Figure 3, the font inside is too small and almost not legible. Same suggestion is valid for Figure 7 and others.
8. Sections 2.4.1.1 and 2.4.1.2, check the equations and insert them properly. Check all equations in the preceding text too.
9. Conclusion is very week, rewrite it and remove all citations from this section.
A favorable decision cannot be made on the manuscript in its current standing.
Comments on the Quality of English Language
Moderate changes are needed
Author Response
Thank you very much for taking the time to revise our manuscript. Please find the response to your comments in the attached file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments and Suggestions for AuthorsThis submission investigated the environmental and human health impacts of E-waste management in Yaoundé and proposed an integrated E-waste management system, as well as policy implementation for increased formal E-waste collection and reduced environmental impacts from informal E-waste treatment. Life cycle assessment was utilized to identify high impact contributing processes within the current E-waste management system, and to determine the most optimum scenario for an integrated system. System dynamics model analysis ascertained the E-waste policy within the integrated E-waste management system. Results show that the integrated E-waste management system can reduce global warming potential, fine particulate matter formation, and human carcinogenic toxicity from 1 ton of E-waste treatment by 27%, 16.3%, and 34% respectively. The manuscript is interesting and needs a revision with consideration of the following comments and suggestions.
(1) In the section of Introduction, the research background provides so much information about E-wastes and they need to be management effectively. While what are the scientific questions? Furthermore, what have been done for the questions? what achievements have been acquired? Please clarify to highlight the contributions.
(2) The manuscript needs to be restructured accordingly to the scientific questions and the storyline. Currently, the contents are broadly and the focus are not emphasized. At least the research background, study review and E-waste management in Cameroon need to be integrated and concised to highlight your contributions. Furthermore, please explain why the two LCA study and efficiency simulation of the proposed policy were put together? What are the relationships?
(3) Table 1, table 5 and figure 1 need to be deleted or at least moved to supporting information because these data come from references and they are not the contributions of this submission.
(4) I suggest that some basic information about the E-waste generation and collection were moved to supporting information. Furthermore, please explain more about the data collection, like how the informal collection of E-wastes was collected? How the LCI data were collected and processed?
(5) How did you conduct the life cycle assessment of the E-waste treatment system? The E-wastes include televisions, computers and refrigerators and mass, component, and treatment ways are different, as well as pollutant emissions. Once the ratios of E-waste changes, all parameters changes. Please explain how did you complete the LCA.
(6) Please polish the English expressions with help from English native speakers to improve its readability and help readers understand the manuscript better.
(7) What about the uncertainty of the data? Please explain.
(8) How about the uncertainty of the results？
(9) What is your contribution? How to test its validity? And please clarify the novelty of the submission.
(10) Some articles may help you understand the situations as follows.
Pre-processing of e-waste in Canada: Case of a facility responding to changing material composition. https://doi.org/10.1016/j.resenv.2022.100069
Distributed recycling system with microwave-based heating for obsolete alkaline batteries.
https://doi.org/10.1016/j.resenv.2022.100071
Review and recommendations for sustainable pathways of recycling commodity plastic waste across different economic regions. https://doi.org/10.1016/j.resenv.2023.100134
Modelling the dynamics of the industrial vanadium cycle using the WORLD7 Integrated Assessment Model. https://doi.org/10.1016/j.resenv.2023.100121
Comments on the Quality of English Languagesee comments.
Author Response
Thank you very much for taking the time to revise our manuscript. Please find the response to your comments in the attached file.
Author Response File: Author Response.docx
Reviewer 3 Report
Comments and Suggestions for AuthorsManuscript ID: urbansci-3037381
Title: Leveraging Life Cycle Assessment and System Dynamics Model Analysis for an Integrated Household E-waste Management System in Yaoundé, Cameroon
Authors: Yannick Esopere et al.
Line 51-59. All this information about 2016-2019 from links [8-9]. Authors should use more recent articles from 2023.
Line 60-69. The same questions. Authors use review from 2008 year. This information is outdated.
Line 84. Avoid more than 3 references for a fact in one sentence. A maximum of 3 in a sentence is allowed for Urban Science. Describe this information in detail.
Line 107. Why authors use information from 2021? Add information from 2023.
Table 3-4. Add information from 2023.
Table 4. I believe authors have a mistake for data from 2020 and 2021. The total quantities for E-waste have the big difference compare from another years.
Table 9. Why the difference between data from figure 1 and table 9? What is about mobile phones?
Figure 3. Bad resolution, authors should improve it to 300DPI.
Section 3. Why authors ignore the mobile phones E-waste treatment?
The conclusions are too extensive, it is necessary to write 3-4 paragraphs, as well as add the numerical values obtained during the study.
Technical errors:
Use CO2, not CO2 in all article text.
Author Response
Thank you very much for taking the time to revise our manuscript. Please find the response to your comments in the attached file.
Author Response File: Author Response.docx
Reviewer 4 Report
Comments and Suggestions for AuthorsCongratulations for the research work. The topic is interesting but there are some missing information that should be corrected:
1.The keywords should be completed with words as sustainable development, weee, recycling, developing countries, development policies, urban spaces
2. The JEL classification that follows keywords in international articles, is missing
3. The Literature review (study review) in a research article, is not a part of the introduction which have to underline the importance of the topic.
4. The research hypothesis are missing or are not clear presented
5. The link between system dynamic modelling for weee recycling and products LCA and climate change is insufficient argued by data
Comments on the Quality of English LanguageEnglish language is ok for this article.
Author Response
Thank you very much for taking the time to revise our manuscript. Please find the response to your comments in the attached file.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsAuthors have made all the suggested changes and have enriched the document, it is now worth accepting for publication.
Reviewer 2 Report
Comments and Suggestions for Authorsit is acceptable.
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors significantly improved the article. It can be accepted in the present from.
