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Atmospherically-fed Earth surface archives such as ombrotrophic peatlands, lake sediments, and ice consistently show an upward increase in Zn concentrations of hitherto unclear origin. Here, we present a combined stable Zn isotope and trace element (Zn, Cd, Ni, Cu, Cr, V, Ta, Pb) dataset for a historically polluted, near-urban bog (Liffey Head) from the east coast of Ireland. This peat record is compared to an archive from a rural site at the west coast of Ireland (Brackloon Wood). Both archives show a clear near-surface increase in Zn deposition, accompanied by periodic deposition in Cr, Ni, Mo, and V suggesting a co-genetic origin of these elements. In the Liffey Head site, biologic upward distillation of nutrients can be excluded as the origin of the elemental enrichments. The differences in the excess metal ratios between the two sites (e.g., Zn/Cd of 426–1564, east, and 77–106, west) are attributed to a higher …