Impact of Chitosan Pretreatment to Reduce Microfibers Released from Synthetic Garments during Laundering

Round 1

Reviewer 1 Report

The article is clearly and concisely written.  The result that chitosan has a useful application in reducing microfibre release is a very important step forward in the field of microplastic pollution research.  Further, the finding that the 0.7% treatment concentration works better than more concentrated solutions is a significant result  illustrating the mechanism by which chitosan acively prevents microfibre release.  Further, the comment that fibres as long as 2 mm can pass the 300 micron filters is highly significant, as this shows the current filter systems are inadequate.  Perhaps the authors might emphasise their comment that they are reducing the production of microfibres, rather than eliminating those microfibres already produced?  This fundamental difference is significant and could lead the way to a perhaps more efficient way to deal with this problem.

I recommend the paper be published, and I see no obvious areas requiring correction or modification.

Author Response

Thanks for review my paper and for your interest.

Reviewer 2 Report

The study tested whether chitosan pretreatment can reduce microfibers in laundering water, and the results are promising. The research topic is essential, and the method is thoughtful and practicable. Overall, the manuscript is well-developed.

 

One concern is that the “n,” the sample size for each type of synthetic material, is unclear. It mentioned “washing test was repeated three times,” but it didn’t state the washing test was done on the same piece of material. Clarify how many samples of each synthetic material (PE. PA, or AC) were used for the washing test. If only one sample was washed three times, the results would not be statistically meaningful.

 

Other things for improvement:

Line 14, reword “aimed to reduce,” e.g., “aimed to test whether the amount of MFs can be reduced…”

Line 23, replace “is” with “be”

Line 92, replace “*” with “X” (mathematical symbol)

Figure 4, the x-axis misses the label and values.

Figure 5, add a sentence to help readers to the meaning of red circles marked in the image (b) and (c).

Table 1, clarify the meaning of the number after “+/-. “ Is it “standard error” or “standard deviation”?

Figure 6, the unit of MFs is unclear. Why the y-axis has the label “MFs/g” here but “MFs/L” in Figure 4?

Figure 7, add a sentence to help readers to the meaning of red arrows marked in the images.

 

Author Response

Thanks for review my paper and for your interest.

I've corrected your comment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Manuscript Number: water-1328471

Impact of chitosan pretreatment to reduce microfibers released from synthetic garments during laundering.

 

The present work investigates the use of a chitosan-based coating to prevent the release of microfibers from clothing in the laundering process. The optimal concentration of the chitosan solution that adheres to the polyester (PE) fibers is obtained, achieving a 95% removal of the released microfibers. This same concentration is tested with polyamide (PA) and acrylic (AC) garments; however, the same results are not obtained as with polyester. No further investigation is being done to find the optimal concentration for PA and AC.

 

 

GENERAL COMMENTS

The research carried out in this study is very interesting, I believe that this type of contaminant will be of great interest soon, however I believe that the study should be completed with a more extensive study that includes the optimal concentration of chitosan in another type of fibers, in addition to polyester and another type of coating agent.

I think the work is interesting and it should be rejected.

SPECIFIC COMMENTS

Section 2.1 Were the two distilled water washes between trials sufficient to remove all MFs? Was a control experiment done to check it?

In figure 1 a mean size distribution is represented, I understand that the experiment has been carried out in triplicate, but the standard deviation is not represented.

In figure 2, is the scale in the image on the right, correct?

The conclusions must be more concrete.

I think the work should be completed with additional assays.

Author Response

Thank you for taking the time to review my paper, and your important comments.

I've corrected your comment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

The authors have corrected what I have been indicated in my review.
I think the work should be accepted.