The impact of iron (Fe) on marine ecology and climate has been a major research focus since the “Iron Hypothesis” was proposed in the 1980s, and substantial data have been accumulated to date. However, analytical methods for dissolved Fe vary significantly across laboratories, research objectives, and projects, creating challenges in synthesizing these datasets. A critical first step is to conduct systematic intercomparisons of results obtained from different methods or laboratories. This study is a significant step toward harmonizing aerosol trace element solubility. Overall, the topic is of very suitable for ATM, and this is a well-written manuscript that presents a logically structured argument supported by rigorous experimental data. A minor revision is suggested before it can be published.

The manuscript would benefit from the following revisions for improved clarity and completeness:

1） Table 1 should comprehensively list all 26 samples analyzed by each institute, with clear definitions provided for abbreviations like C1-C7 in either the caption or a footnote.

2） The presentation of methodological information could be enhanced by:

a) Consolidating all sample details (methods and sample numbers per institute) into Table 1;

b) Creating a separate Table 2 summarizing all leaching methods with corresponding sample counts

3) While the authors have noted the limitation regarding standard solutions, the discussion should further emphasize how using identical standard solutions across laboratories would reduce calibration variability and improve intercomparability.

4）Figure 1 could be strengthened by including additional trajectory data (e.g., altitude or pressure) where available. An analysis of Fe solubility across different airmasses source samples (including the data comparison in Figure 7) is not essential unless these source differences directly affect methodological variations.

5）Table 5 requires clarification of undefined terms like “UEA-a” and “UEA-” through either table footnotes or explanatory text.

6）To improve accessibility, schematic diagrams illustrating all leaching procedures could be included in the Supplementary Information. Readers can quickly grasp all key information from this paper alone, improving both readability and audience engagement.

7）Appropriate references should be added to support the discussion at Line 512.

This manuscript presents a comparison of trace elements measurements in aerosols using eight different leaching methods from different institutes. It is important to have good practical protocols to determine the contents or solubility of elements. The manuscript found significant variations among the leaching methods in determining the elemental contents in aerosols at this specific sampling location. There are two comments that I wish the author can address in the revision. (1) In the Figures 3,4,5, It would be helpful to convert the mass to concentration in the atmosphere, which may be easy for comparison with other studies. The samples marked with YS show higher variations in elemental masses and some of them have much higher values. Please comment on the potential reasons for this. (2) It would be interesting to see the overall variations among these leaching methods for each element in each sample. For example, showing the ratio (to the median or means of all eight methods) for each leaching method (and elements). Such information could give us a general idea of the magnitude of variations that one may expect. Please include a summary or section of this information.