Chemical reactivity theory to analyze possible toxicity of microplastics: Polyethylene and polyester as examples

Ana Martínez; Andrés Barbosa

doi:10.1371/journal.pone.0285515

Peer Review History

Original SubmissionApril 23, 2023
18 Sep 2023 Decision Letter - Arumugam Sundaramanickam, Editor PONE-D-23-12236Microplastics found in Antarctic penguins: chemical reactivity theory to analyze possible toxicityPLOS ONE Dear Dr. Martínez, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. The manuscript needs extensive correction. I request the authors carefully read all the reviewers' comments and edit the manuscript accordingly. . Please submit your revised manuscript by Nov 02 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. 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The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: N/A ****** 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: Yes Reviewer #2: Yes ****** 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: Yes Reviewer #2: Yes ****** 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: Dear Editor, Thank you for inviting me to review the current manuscript. I reviewed the manuscript and the manuscript need correction please check the following comments and points. In the abstract, before stating the percentage of polymers, it is better to explain the sources of pollution in the region. Penguins were mentioned in the title, but no results were given regarding the number of microplastics and their size in the study area. How were polymers identified? Fig 1- Which one is polyethylene and which one PET? Show in lowercase letters. The discussion part of the results less compared with other studies. The conclusion is very similar to the abstract. Reviewer #2: The scope of this study is interesting and timing. Since we still do not know much about the real harm of micro- and nanoplastics continuously interacting with biological systems (from animals to humans), it is a research priority to predict their toxicity, as clearly stated in the introduction. However, the authors focus on only two polymers found in penguin species (based on a single study) but they do not discuss why it is important in the context. The chemical reactivity theory can be applied to any context (I.e., any plastic polymer) and the results here can be associated to any organisms). What is the link to penguins rather than other species in which PE and PET have been found? If penguins are key in this study, the authors should first review all current literature on microplastic contamination in penguins and enlarge their study to depict a more comprehensive toxicity assessment. Moreover, the authors discuss specific effects on DNA, which again can be referred to any biological system. What are the implications for penguin populations and Antarctic ecosystems? If the findings are too general, I suggest to simply remove penguins from the title. The article readability can be improved by rechecking the grammar and trying to build more articulated sentences, which sometimes are very short. Some errors are reported below: (not having line numbers made the revision more difficult) Additional comments: Introduction This study is based on citation n.27 (3 penguins species), but there are several studies on the subject, which should be at least mentioned on the introduction, then the authors should explain why they chose to focus only on findings from citation 27 (based on more samples? from more sampling sites?), as it is likely that penguins are not exposed to PE and PET only: https://doi.org/10.1038/s41598-019-50621-2 https://doi.org/10.1038/s41598-023-39844-6 https://doi.org/10.1016/j.envint.2019.105303 No microplastic were also found in emperor penguins, this should be mentioned in the introduction as well: https://doi.org/10.1016/j.scitotenv.2022.158314 “There is also no theoretical research on potential toxicity of these polymers” There are model studies available on in vitro nanoplastic—cell interactions (e.g., https://doi.org/10.1021/jz402234c), although based on a different approach. I suggest listing some examples in which chemical reactivity theory has been applied to environmental risk assessment. “The results of this research help…” change to: can help “…and may determine which of the two plastics found in penguins is potentially more dangerous.” Please specify that you are referring to two types plastic polymers based one study. …until the chain length is greater than 2 nm” change to: was Rephrase to: In Figures 3 and 4 the optimized structures of the models investigated are shown. The correspondent length of the oligomer is also reported. “As was explained in the introduction, apparently micro- and nanoplastics may induce oxidative stress. To investigate possible oxidative stress, …” Rephrase to, deleting previous phrase: To investigate possible oxidative stress caused by micro- and nanoplastics,… In page 6 there are some small errors to correct, please check the text again. Please avoiding the use of English possessive (‘s) with polymers. “… we calculated adenine, thymine, cytosine and guanine.” In what sense? Add details “The idea is to…” I suggest to change, continuing the previous sentence with as: in order to “Polyester can oxidize nucleobases and therefore, microplastics of PET can be harmful. Although it was found that penguins have less polyester than polyethylene, nucleobases might transfer electrons to polyester and therefore it could affect more pinguin’s health.” Add details referred to this statement with actual examples of previous studies showing significant damages following exposure to PET microplastics to support your findings. I suggest to add reference/s to page 9 to support the statements. The same applies to page 11: there are many in vitro/in vivo studies with model micro and nanoplastics, the authors should refer to those for comparison and to support their hypothesis. Conclusions “Micro- and nanoplastics can have long-term stability in various biological media (please add examples of biological media) Change “obvious” to: clear Change “say” to: state “no toxic effects of micro and nano- have been observed”. I suggest to add: considering the diversity of biological systems. “…for three reasons”. I suggest to list the reasons from the least to the most harmful, as in the abstract. “Although it was found that penguins have…” change “have to: can ingest As in this study only PE and PET are considered and no mention of the biological system I suggest the authors to refer to their results are first or preliminary. ****** 6. 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: No Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0285515.r001
Revision 1
25 Sep 2023 Author Response PONE-D-23-12236 Old title: Microplastics found in Antarctic penguins: chemical reactivity theory to analyze possible toxicity. New Title: Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examples. Dear Arumugam Sundaramanickam, PhD Academic Editor PLOS ONE Please find enclose the revised version of the manuscript entitled Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examples. In what follows we respond to each point raised by the academic editor and reviewers. All questions were answered to the best of our ability. We hope you find this version suitable for publication. Kind regards, Prof. Ana Martínez UNAM Reviewer #1: In the abstract, before stating the percentage of polymers, it is better to explain the sources of pollution in the region. Penguins were mentioned in the title, but no results were given regarding the number of microplastics and their size in the study area. How were polymers identified? Author's response: Following Reviewer #2's suggestion, we removed all information regarding penguins. Therefore, this information is not necessary. Reviewer #1: Fig 1- Which one is polyethylene and which one PET? Show in lowercase letters. Author's response: Figure 1 was modified accordingly. Reviewer #1: The discussion part of the results less compared with other studies. Author's response: We modified the discussion accordingly Reviewer #1: The conclusion is very similar to the abstract. Author's response: We modified the abstract as follows: Micro- and nanoplastics are widespread throughout the world. In particular, polyethylene (PE) and polyethylene terephthalate or polyester (PET) are two of the most common polymers, used as plastic bags and textiles. To analyze the toxicity of these two polymers, oligomers with different numbers of units were used as models. The use of oligomers as polymeric templates has been used previously with success. We started with the monomer and continued with different oligomers until the chain length was greater than two nm. According to the results of quantum chemistry, PET is a better oxidant than PE, since it is a better electron acceptor. Additionally, PET has negatively charged oxygen atoms and can promote stronger interactions than PE with other molecules. We found that PET forms stable complexes and can dissociate the guanine-cytosine nucleobase pair. This could affect DNA replication. These preliminary theoretical results may help elucidate the potential harm of micro- and nanoplastics. Reviewer #2: However, the authors focus on only two polymers found in penguin species (based on a single study) but they do not discuss why it is important in the context. The chemical reactivity theory can be applied to any context (I.e., any plastic polymer) and the results here can be associated to any organisms). What is the link to penguins rather than other species in which PE and PET have been found? If penguins are key in this study, the authors should first review all current literature on microplastic contamination in penguins and enlarge their study to depict a more comprehensive toxicity assessment. Moreover, the authors discuss specific effects on DNA, which again can be referred to any biological system. What are the implications for penguin populations and Antarctic ecosystems? If the findings are too general, I suggest to simply remove penguins from the title. Author's response: We agree with this statement. Penguins are not key to this research. We included them because one of us found microplastics in penguins, but this is no reason to preserve the idea of penguins. In this new version we eliminate all information related to penguins. Reviewer #2: The article readability can be improved by rechecking the grammar and trying to build more articulated sentences, which sometimes are very short. Some errors are reported below: (not having line numbers made the revision more difficult) Author's response: We corrected the errors and review the grammar from the beginning. Reviewer #2: This study is based on citation n.27 (3 penguins species), but there are several studies on the subject, which should be at least mentioned on the introduction, then the authors should explain why they chose to focus only on findings from citation 27 (based on more samples? from more sampling sites?), as it is likely that penguins are not exposed to PE and PET only: https://doi.org/10.1038/s41598-019-50621-2 https://doi.org/10.1038/s41598-023-39844-6 https://doi.org/10.1016/j.envint.2019.105303 No microplastic were also found in emperor penguins, this should be mentioned in the introduction as well: https://doi.org/10.1016/j.scitotenv.2022.158314 Author's response: Following the suggestion of this reviewer, we delete all information about pinguins. Reviewer #2: “There is also no theoretical research on potential toxicity of these polymers” There are model studies available on in vitro nanoplastic—cell interactions (e.g., https://doi.org/10.1021/jz402234c), although based on a different approach. I suggest listing some examples in which chemical reactivity theory has been applied to environmental risk assessment. Author's response: Following this suggestion, we added more references and the following paragraph: There are some publications on molecular simulations to determine the effect of nanometric polystyrene particles [32] and the theory of chemical reactivity has been used to study the environmental risk [33-35] of different substances, but there are no studies on oxidative stress or the direct interactions of nanoplastics with DNA nitrogen bases. For this reason, … New references: 32. Rossi G, Barnoud J, Monticelli L. Polystyrene Nanoparticles Perturb Lipid Membranes J. Phys. Chem. Lett. 2014; 5, 241−246. dx.doi.org/10.1021/jz402234c 33. Wang Q, Zhang Y, Rogers WJ, Mannan MS. Molecular simulation studies on chemical reactivity of methylcyclopentadiene. Journal of Hazardous Materials 2009; 165, 141–147 doi: 10.1016/j.jhazmat.2008.09.087 34. Rawat P, Singh RN. Experimental and theoretical study of 4-formyl pyrrole derived aroylhydrazones. Journal of Molecular Structure 2015; 1084, 326–339 http://dx.doi.org/10.1016/j.molstruc.2014.12.045 35. Villaverde JJ López-Goti C, Alcamí M, Lamsabhi AM, Alonso-Pradosa JL, Sandín-España P. Quantum chemistry in environmental pesticide risk assessment. Pest. Manag. Sci. 2017; 73: 2199–2202 doi: 10.1002/ps.4641 Reviewer #2: “The results of this research help…” change to: can help “…and may determine which of the two plastics found in penguins is potentially more dangerous.” Please specify that you are referring to two types plastic polymers based one study. …until the chain length is greater than 2 nm” change to: was Rephrase to: In Figures 3 and 4 the optimized structures of the models investigated are shown. The correspondent length of the oligomer is also reported. “As was explained in the introduction, apparently micro- and nanoplastics may induce oxidative stress. To investigate possible oxidative stress, …” Rephrase to, deleting previous phrase: To investigate possible oxidative stress caused by micro- and nanoplastics,… In page 6 there are some small errors to correct, please check the text again. Please avoiding the use of English possessive (‘s) with polymers. “The idea is to…” I suggest to change, continuing the previous sentence with as: in order to. “Polyester can oxidize nucleobases and therefore, microplastics of PET can be harmful. Change “obvious” to: clear Change “say” to: state “no toxic effects of micro and nano- have been observed”. I suggest to add: considering the diversity of biological systems. “…for three reasons”. I suggest to list the reasons from the least to the most harmful, as in the abstract. “Although it was found that penguins have…” change “have to: can ingest Author's response: We made all these correction in this new version. We delete all information concerning penguins. Reviewer #2: “… we calculated adenine, thymine, cytosine and guanine.” In what sense? Add details Author's response: To answer this question, we modified the paragraph as follows: we optimized geometries of adenine, thymine, cytosine and guanin, and we calculated the electron transfer properties. Reviewer #2: Although it was found that penguins have less polyester than polyethylene, nucleobases might transfer electrons to polyester and therefore it could affect more pinguin’s health.” Add details referred to this statement with actual examples of previous studies showing significant damages following exposure to PET microplastics to support your findings. Author's response: We delete all information about pinguins so this correction is not necessary. Reviewer #2: I suggest to add reference/s to page 9 to support the statements. The same applies to page 11: there are many in vitro/in vivo studies with model micro and nanoplastics, the authors should refer to those for comparison and to support their hypothesis. Author's response: We performed a review of the literature and found no evidence on the comparison of toxicity of PP and PET. I'm afraid I don't understand what evidence the reviewer is suggesting, but I'm interested in following this suggestion as soon as I get the idea. Reviewer #2: “Micro- and nanoplastics can have long-term stability in various biological media (please add examples of biological media) Author's response: This is a mistake. We were thinking on the environment. The new sentence is as follows: “Micro- and nanoplastics can have long-term stability under environmental conditions. Reviewer #2: As in this study only PE and PET are considered and no mention of the biological system, I suggest the authors to refer to their results are first or preliminary. Author's response: We added this sentence at the end of the abstract and conclusions. Attachments Attachment Submitted filename: letterPLOSONEmartinezRESPONSE.docx https://doi.org/10.1371/journal.pone.0285515.r002
15 Nov 2023 Decision Letter - Arumugam Sundaramanickam, Editor PONE-D-23-12236R1Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examplesPLOS ONE Dear Dr. Martinez Vazquez, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Dec 30 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Arumugam Sundaramanickam, PhD Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] 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 #2: All comments have been addressed ******** 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: Yes Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: N/A ****** 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 #2: Yes ****** 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 #2: Yes ****** 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: Authors have responded effectively to the initial querries raised. Since the necessary corrections have been made, it is appropriate to publish it as it is. Reviewer #2: "...there are no studies on oxidative stress or the direct interactions of nanoplastics with DNA nitrogen bases" this should be changed as there are several studies on ox stress and nanoplastics, for example: https://doi.org/10.1016/j.envint.2023.107899 https://doi.org/10.3389/fpls.2022.1027608 https://doi.org/10.3390/antiox11020193, and as reviewed in https://doi.org/10.1016/j.scitotenv.2023.163144 Regarding the references to add to support these statements: "In vivo uptake and transport of nanoplastics depend on their own structure and properties, such as chemical composition" the authors can easily refer to reviews summarising these concepts as https:// doi.org/10.3390/nano11081903 All other comments have been addressed ****** 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: Mohammad Gholizadeh Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0285515.r003
Revision 2
15 Nov 2023 Author Response Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examples. Dear Arumugam Sundaramanickam, PhD Academic Editor PLOS ONE Please find enclose the revised version of the manuscript entitled Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examples. In what follows we respond to each point raised by the academic editor and reviewers. All questions were answered to the best of our ability. We hope you find this version suitable for publication. Kind regards, Prof. Ana Martínez UNAM Reviewer #1: Authors have responded effectively to the initial querries raised. Since the necessary corrections have been made, it is appropriate to publish it as it is. Reviewer #2: "...there are no studies on oxidative stress or the direct interactions of nanoplastics with DNA nitrogen bases" this should be changed as there are several studies on ox stress and nanoplastics, for example: https://doi.org/10.1016/j.envint.2023.107899; https://doi.org/10.3389/fpls.2022.1027608 https://doi.org/10.3390/antiox11020193, and as reviewed in https://doi.org/10.1016/j.scitotenv.2023.163144 Author's response: They are very interesting references, which are now included in this new version. The following paragraph is also added. There are also studies on oxidative stress and nanoplastics [36-40] but there are not theoretical studies on oxidative stress or the direct interactions of nanoplastics with DNA nitrogen bases. 36. Ekner-Grzyb A, Duka A, Grzyb T, Lopes I, Chmielowska-Ba ̨k J. Plants oxidative response to nanoplastic. Front. Plant Sci. 2022, 13:1027608. doi: 10.3389/fpls.2022.1027608 37. Ferrante MC, Monnolo A, Del Piano F, Mattace Raso G, Meli R. The pressing issue of micro- and nanoplastic contamination: profiling the reproductive alterations mediated by oxidative stress. Antioxidants 2022, 11: 193 https://doi.org/10.3390/ antiox11020193 38. Ding R, Ma Y, Li T, Sun M, Sun Z, Duan J. The detrimental effects of micro-and nano-plastics on digestive system: An overview of oxidative stress-related adverse outcome Science Tot. Env. 2023, 878: 163144. https://doi.org/10.1016/j.scitotenv.2023.163144 39. Zhou Y, He G, Jiang H, Pan K, Liu W. Nanoplastics induces oxidative stress and triggers lysosome-associated immune-defensive cell death in the earthworm Eisenia fetida. Env. Int. 2023, 174: 107899. https://doi.org/10.1016/j.envint.2023.107899. Regarding the references to add to support these statements: "In vivo uptake and transport of nanoplastics depend on their own structure and properties, such as chemical composition" the authors can easily refer to reviews summarising these concepts as https:// doi.org/10.3390/nano11081903 The reference is already added as follows: 62. Corsi I, Bellingeri A, Eliso MC, Grassi G, Liberatori G, Murano C, Sturba L, Vannuccini ML, Bergami E. Eco-interactions of engineered nanomaterials in themarine Environment: towards an eco-design framework. Nanomaterials 2021, 11: 1903. doi.org/10.3390/nano11081903 The reference number was also updated and indicated in red. Attachments Attachment Submitted filename: letterPLOSONEmartinezRESPONSE2.docx https://doi.org/10.1371/journal.pone.0285515.r004
2 Feb 2024 Decision Letter - Arumugam Sundaramanickam, Editor Chemical reactivity theory to analyze possible toxicity of microplastics: polyethylene and polyester as examples PONE-D-23-12236R2 Dear Dr. Martinez Vazquez, 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. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Arumugam Sundaramanickam, PhD Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0285515.r005
Formally Accepted
13 Feb 2024 Acceptance Letter - Arumugam Sundaramanickam, Editor PONE-D-23-12236R2 PLOS ONE Dear Dr. Martínez, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Professor Arumugam Sundaramanickam Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0285515.r006

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