Monitoring of the Surfactants in Surface Waters in Slovakia and the Possible Impact of COVID-19 Pandemic on Their Presence

Round 1

Reviewer 1 Report

The paper reports the surfactant concentrations of river water samples from two basins for 2019 and 2020. The background and the structure of the study are well constructed. However, the results and discussions need some improvements. This version of the manuscript briefly indicates the enrichments of surfactant concentrations of samples between 2019 and 2020. Naturally, it is interpreted as the effect of the Covid-19 pandemic. But some more evidence is needed for this interpretation. Please find some suggestions below in addition to the attached file;

- If it is possible some more chemical analysis results supporting your results will be very helpful.

- a new map showing the industrial activities remarked in the text; including the %differences to 2019 values of concentration of samples and the population of the cities (at least as growing symbols).

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript aimed on the monitoring the presence of the personal care products in surface waters in two river basins in the Slovak Republic. The monitoring results indicated the presence of the personal care products in the aquatic environment, where pose an ecological and environmental risk. The results are important for the knowledge of the presence of surfactant in water. I have some comments as follow:

 

Line 36: Herbicides are pesticide. Please review the the sentence.

Figure 2: The calibration curve for determining the content of surfactants can be in supplementary material.

Materials and Methods: What are the concentrations used in the test waters? It can be added in table 1. This part of the methodology is not clear.

 

Line 220: What is the analysed parameters to state that  Hron has very pure water?

Line 274: this sentence is not clear: … “Daphnia magna even at a concentration of 0.7 mg/L….”

There is lower and higher concentrations too.

Line 277: In my opinion the test using  Daphnia magna is a model organism to acess acute toxicity, not exactly indicator of pollution.

Line 280-281: Was any other substance analyzed besides the surfactants? it is not possible to justify the effect on D. magna only based on the surfactants.  

Conclusion: The last part of the conclusion should be focused in the results of the study. The authors did not study the risk assessment and other substances, that were not analysed, can be present in the water samples.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Dear Author(s),

Thank you for your valuable contribution to the revision.

I'm sorry, but the data is still insufficient to link enrichments to the COVID-19 Pandemic. Yes, that's the most likely possibility for the differences in concentrations between 2019 and 2020. However, we need some strong evidence for a scientific paper. That's why I advised Point 1 in your response file. I tried to mention some additional chemical data supporting your conclusion about Covid -19 effect on water chemistry instead of any limits.

If you don't have any data about that I have one more piece of advice It will be helpful to share long-term surfactant concentrations if you have (including before and after the Covid-19 Pandemic period). Otherwise, it will be better to change the title as "... the possible impact COVID-19 Pandemic...". Because with this data set and interpretations, it is not possible to definitely mention that the enrichments of surfactant concentrations are related to Covid-19 Pandemic. 

Finally, Fig.1 is difficult to examine. I'll advise you to separate the Horn and Nitra Basins as Fig-1A and 1B.

Kind Regards.  

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 3

Reviewer 1 Report

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