On the Scarce Occurrence of Arsenic in Vineyard Soils of Castilla La Mancha: Between the Null Tolerance of Vine Plants and Clean Vineyards

Round 1

Reviewer 1 Report

I found your paper of interest and in my opinion should be published. The research topic has been investigated extensively in many countries of the world, but as stated by the authors, little information is available in the studied region. All these aspects are interesting since they contribute to information on the concentration of As in vineyard soils. Nevertheless, there are some deficiencies in the article as far as layout and content in the text are concerned.

Line 16…all the soil orders in this territory… It is assumed that they are orders of Soil Taxonomy classification. Maybe this should be added.

Line 26. Our results suggest that vineyards in CLM are clean of contamination, because As in … Maybe it should be rewritten: Our results suggest that vineyards in CLM are clean of contamination by As, because this element in …

Figure 1. Identification of the Arsenic element. Perhaps it would be more logical: Basic data of Identification of the Arsenic element.

Line 48. According to the OIV. Please add (International Organisation of Vine and Wine).

Line 59. If it is possble please add reference to: However, they were forbidden at the end of the twentieth century.

Line 119. Soil samples (n = 20) were collected from the corresponding 10 soil vineyard profiles. That means two soil samples per profile?. Please clarify.

Author Response

See attached file

Author Response File: Author Response.docx

Reviewer 2 Report

The topic of the manuscript is important and implications of the findings are worthy of further examination. The conclusions and presented data are not strong and conclusive to support the concluding statements of “no toxicological risk”.  The following are some noted deficiencies and needs for clarification within the manuscript:

- The introduction section is lacking reference source citation in some segments, including: Lines 36, 45; lines 55-59, line 65; lines 66-72; lines 77-78; lines 82-85.

- Line 36: Explain what is meant by oral bioavailability.

- Line 73: Explain further what is meant by “experience has shown….”; what are some examples of specific experiences that are being referred to?

- Line 108: Define what is meant by “bioexclusion”.

- Explain how the 20 samples were collected. The abstract section indicates samples were collected from more than 100 location. The sample collection methods is unclear in the methods section.

-Line 139: Please explain further about the quality control procedures and reference materials, control samples, known positive standards used for soil and leaves samples matrices, and what was considered as acceptable coefficient of variation.

-Line 158: Describe what “surface and subsurface horizons” represent, what soil depth is regarded as subsurface?

-Line 162: Explain what is meant by “mixed farming”.

- Line 164-165: Explain the basis for this conclusion about “root system uptake”.

-Line 167: Explain the “pedological processes”.

-Line 169: Results indicate no arsenic content in the leaves, while in the abstract (line 23) it is noted that two samples showed arsenic accumulated “somewhat” in the leaves. Please explain further.

-Line 179: Explain what is meant by “parent materials”.

-Line 203: Explain the comment about “remaining difficulties and uncertainties”.

- Line 205: This statement should be supported by data on arsenic levels in the fruit and wines produced from the studied region.

- Line 220: Define the abbreviation OM; organic matter?

-Line 228: Explain what level is regarded as “low arsenic”. Also, the analytical method detection limit should be noted for the arsenic analysis in the methods section and the data summary table.

- The definitive statement of “no toxicological risk” should be supported by data and risk assessment analysis based on consumption levels.

- In the conclusions section, evidence from other similar studies should be included to support the hypothesis that absence of arsenic in the leaves is indicative of no risk from arsenic presence in the fruit and produced wine.

The English language quality is acceptable; editorial improvements can be made.

Author Response

See attached file

Author Response File: Author Response.docx

Reviewer 3 Report

This manuscript described the As content in the soil and leaves of vineyards in the Castilla La Mancha region. The authors measured arsenic concentrations in soil ranging from 0 to 24.8 mg kg-1, averaging 7.3 mg kg-1 at the surface and 8.2 mg kg-1 below ground. In addition, the As concentration in grape leaves was zero. It was concluded that there were no toxicological risks to making wine from grapes from these vineyards. While the study's focus is interesting, there are some major concerns that the authors should address as follows;

1.     Some parts of the manuscript are difficult to understand. English must be edited with a help of a native English-speaking scientist or a commercially available English proof reader. Especially in “Abstract”, it was very confusing whether As was accumulated in the vineyard or not, and whether there were any vine leaves in which As was recognized.

2.     Figure 1 makes no sense.

3.     Please standardize the notation of arsenic to either arsenic or As. In the case of As, specify arsenic (As) at the first appearance.

4.     Regarding sampling, at least three samples should be taken from one site, if possible. There was no guarantee that the soil and vine leaf arsenic values presented by the authors are representative of the vineyard. Please obtain additional samples for experimental reproducibility (precision) and increased accuracy of arsenic values.

5.     For research purposes, arsenic values in grape berries (skin and pulp) are also required in addition to grape leaves.

6.     Please add to the footnote of Table 1 that the grapes grown are Tempranillo.

7.     The authors used XRF to measure arsenic; however, the values obtained with XRF are semi-quantitative. For the purposes of this study, arsenic must be quantified, at least to calculate an accurate BCF. Soil and grape leaves, preferably grape pulp and skins, should be ashed with acids, and the amounts of arsenic should be determined by atomic absorption spectroscopy or ICP mass spectroscopy.

1.     Some parts of the manuscript are difficult to understand. English must be edited with a help of a native English-speaking scientist or a commercially available English proof reader. Especially in “Abstract”, it was very confusing whether As was accumulated in the vineyard or not, and whether there were any vine leaves in which As was recognized.

Author Response

See attached file

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The authors have addressed all the review comments. The revised manuscript is improved with citation of the additional references and removal of comments not supported by actual data from this or prior research.

The authors can consider including the detailed and helpful descriptions provided within their peer-review response cover letter in the revised manuscript. This would make it easier for readers who are not soil scientists to better understand the pointed results and discussions that were highlighted in the peer-review.

Additionally, it would be helpful to note the minimum analytical detection limit for arsenic under the methodology section (and the data table or footnote), since most of the values are noted as 0.0. Also, it is recommended that in the methodology section, the utilized reference source and values for the quality assurance and acceptable precision and accuracy criteria be noted. For example, acceptable level of standard deviation.

Author Response

Comments and Suggestions for Authors:

-The authors have addressed all the review comments. The revised manuscript is improved with citation of the additional references and removal of comments not supported by actual data from this or prior research.

Response: Thanks you for the comments. We are very grateful for your encouraging and the positive evaluation of our research.

-The authors can consider including the detailed and helpful descriptions provided within their peer-review response cover letter in the revised manuscript. This would make it easier for readers who are not soil scientists to better understand the pointed results and discussions that were highlighted in the peer-review.

Response: Thanks you for the comments. We are very grateful for your encouraging and the positive evaluation of our research. We have included the comments regarding:

• bioexclusion,
• pedological processes
• parent material

-Additionally, it would be helpful to note the minimum analytical detection limit for arsenic under the methodology section (and the data table or footnote), since most of the values are noted as 0.0. Also, it is recommended that in the methodology section, the utilized reference source and values for the quality assurance and acceptable precision and accuracy criteria be noted. For example, acceptable level of standard deviation.

Response: Thanks you for the comments- The low limit detection (LLD) was 0.3. The quality assurance and acceptable precision of the level of standard deviation was 3.7.

On behalf of the authors,

Sincerely

R. Jiménez Ballesta

Reviewer 3 Report

It's a pity that grape berries and skins are not measured, but the reviewer understands the author's situation.

Author Response

Comments and Suggestions for Authors:

It's a pity that grape berries and skins are not measured, but the reviewer understands the author's situation.

Response: Thank you very much for your comment and understanding.

On behalf of the authors,

Sincerely

R. Jiménez Ballesta