A Review on Contaminants of Emerging Concern in the Environment: A Focus on Active Chemicals in Sub-Saharan Africa

S/N

Reviewers Comments

Response

General

1.

Thanks for the comments

2.

Kindly provide the motivation for this work.

Provided in the abstract

3.

How the present work gain novelty needs to be addressed clearly.

4.

Chemical pesticides are critical materials with great potential for environmental risk when coming into the food chain. Discussing chemical pesticides and applying biological approaches is recommended, especially in more recent papers such as DOI: 1186/s40538-021-00254-3 (In regarding sections 3 and 4).

Thanks, right reference included and, on the section, how to overcome challenges the matter is discussed line 728-743

5.

The table should not have horizontal lines. It is recommended to correct Table 1 and Table 2 (c, d, e, g, h, i, j, l).

Removed all lines

6.

Some important heavy metals (such as Chromium, Cadmium, lead) that have the main role in the pollution environment were not mentioned in this work.

Removed to retain the main focus

7.

Nowadays, medicinal plants-based nanomaterials such as biogenic nanogolds have mainly portion in green pharmacy. The authors did not cite and discuss proper references, especially DOI: 10.3390/nano11082033, DOI: 1016/j.jddst.2020.101987 (In regarding line 678).

Thanks, right reference included

8.

On page 3, the author has mentions “Chemicals that are environmentally persistent and have tendency to bioaccumulate have a great potential for environmental risk especially when such chemicals come into contact with drinking water supplies and the food chain”. Provide proper references. https://doi.org/10.1002/9781118939314.ch12; https://doi.org/10.1002/9781119577119.ch8

Thanks, right reference included

9.

Bioremediation is a pathway to overcome the harmful compounds of ACs. It will be better if the authors can pay attention to this.

Introduced as measures to overcome ACs in the environment

Line 728-746

11.

Natural active materials or natural antibiotics are worthy alternatives to reduce contamination caused by the active chemical. It is recommended if authors can discuss these

12.

Improve the English language of the script.

Comments taken

S/N

Reviewers Comments

Response

General

1.

This is a very interesting review that addresses the environmental concern of active chemicals (and their mixtures) in sub-Saharan Africa. The manuscript is well written and organized. I also find it very informative and necessary for boosting further researches on this topic in the region. Thus, I would recommend it for publication after some minor revisions.

Thanks for the comments

2.

Lines 75-87. Is there an increasing trend of published papers on this topic recently? What are the time range of the papers found in the review? Please add this information in this section.

Rephrased and information added

3.

Lines 82-83. Separate all databases with commas.

Adopted

4.

Lines 279-292. I found the discussion in this section off topic. How climate change, coral and reefs degradation, illegal fishing, etc in Madagascar are directly connected to this review objectives (presence of active chemicals in the environment)? I suggest rewritting this section.

Rephrased

5.

Line 369. What is Bdl in the table?

Defined

6.

Line 392. Consider removing "a possibility of".

Removed

7.

Line 412. Consider removing the last "and".

Removed

8.

Lines 473-476. The example for Cape Verde is confusing because the polluted environment is air, while in the other sections mostly water matrices have been considered.

There was no immediate work reporting presence of these substances in other matrices. Through their presence in air may result from their volatility and water, soil and effluents may be the main source

9.

Line 487. Why children are more susceptible than adults? Please explain and cite references.

Explained and reference added

10.

Line 505. I believe using the air quality as an example is confusing given this review objectives and scope (shown in Lines 78-80).

There was no immediate work reporting presence of these substances in other matrices. Through their presence in air may result from their (Or else we have to remove the information)

11.

Line 611. Figure 1 has not been introduced in the text. Please make it clear if this figure is a result of this review analysis or extracted from other paper.

Figure 1, cited in text

12.

Lines 628-630. Please review writing in this part.

Rephrased and reference added