Provenance of Anthropogenic Pb and Atmospheric Dust to Northwestern North America. Environmental Science & TechnologyKoffman, Bess G.⋅Saylor, Patrick⋅Zhong, Roujia⋅Sethares, Lily⋅Yoder, Meg F.⋅Hanschka, Lena⋅Methven, Taylor⋅Cai, Yue⋅Bolge, Louise⋅Longman, Jack⋅Goldstein, Steven L. and Osterberg, Erich C.