Response to comment on “Primary sources and toxicity of PAHs in Milwaukee‐area streambed sediments”—The authors' reply

Response to Comment on “Primary Sources of Polycyclic Aromatic Hydrocarbons to Streambed Sediment in Great Lakes Tributaries Using Multiple Lines of Evidence”

“…We respectfully disagree with the claim that the coal tar dust profile used in our study is representative of an urban background signal, and we have responded to this claim previously (Baldwin et al 2017). Dr. O'Reilly compares the PAH profiles in our samples with those of "urban background" reported in Stout et al (2004).…”

“…There is, therefore, an important distinction between fresh coal tar sealant product and coal tar dust, as has been discussed previously (Baldwin et al 2017). Within days of application, the PAH profile of the coal tar sealant product is no longer representative of the coal tar sealant remaining on the pavement (Van Metre et al 2012) nor of the coal tar dust that washes off the pavement into the stream.…”