Dear Jakko and coauthors,

I appreciate the substantial revisions you have made in response to the reviewers comments. I have two additional/correlated comments of my own that I think would further strengthen the manuscript. Once these are addressed I will be happy to accept the paper for publication in ACP.

1) Reviewer 2 mentioned a couple of parts of the manuscript which struck them as long yet, in the revisions, little was cut while many things were added. The introduction especially strikes me as overly detailed and I would recommend rewriting to include only the background information necessary for the reader to follow the work at hand. As written it is a very thorough literature review with one to two sentences on each of many references. I would recommend reorganizing so that you have three or four thematic paragraphs in which you discuss, for example, 1) previous studies that have looked at health effects of RWC aerosol, 2) prior findings of fractional contribution of RWC sources in Europe, 3) findings about RWC in other places (if necessary) and so on.

2) Figure 4 does not need to be 3d or shown with perspective. I recommend revising to be a normal bar graph.

Dear authors,

I agree that the introduction is more streamlined now and am happy to accept your paper for publication in ACP.

Anne