Please italicize m/z throughout the manuscript

Line 38 cites 10-70% and line 54 cites 30-90% as water-insoluble fraction of OM, and the same references are listed in both case. Please use the same numbers in both case.

Line 102: Soluble particles were isolated -> Insoluble particles were filtered out

Line 160: one of the two < signs should be changed to > on this line

Line 176: efficacious -> effective

Line 372: replace “NO3” with “-ONO2”

Line 384: missing period in e.g, (should be e.g.,)

Line 398: “PSOM is able to dissolve” -> “pyridine is able to dissolve”

Line 398: “that WSOM does not” -> “that water does not”

Line 450: “quantitatively small” is unclear; I would rephrase this sentence

References: capitalization of titles is not uniform

References: some of the author initials are missing. Examples from the top of the reference list:
Alfarra, M. should be Alfarra, M.R.
Andreae, M. should be Andreae, M.O.
Altieri, K. should be Altieri, K.E.
Bateman, A. should be Bateman, A.P.
And so on. Please check all references carefully, especially the ones where each other has only one initial (which is rather unlikely to happen).

Line 562: “TSigaridis” should be changed to “Tsigaridis”

Figure 1: The numbers in the table are perhaps too small. I would increase the text size so that they are readable in the print version of the paper.

Figure 2: It would be good to make figure label style more uniform between figures. The text sizes are too small for some of the text entries such as the legend and X-axis tick labels.

Figure 3: It is hard to see black number on blue in the pie-charts (at least in the printed version). Make the numbers bold?