Abstract
AbstractStable isotope compositions can potentially be used to trace atmospheric Cd inputs to the surface ocean and anthropogenic Cd emissions to the atmosphere. Both of these applications may provide valuable insights into the effects of anthropogenic activities on the cycling of Cd in the environment. However, a lack of constraints for the Cd isotope compositions of atmospheric aerosols is currently hindering such studies. Here we present stable Cd isotope data for aerosols collected over the Tropical Atlantic Ocean. The samples feature variable proportions of mineral dust‐derived and anthropogenic Cd, yet exhibit similar isotope compositions, thus negating the distinction of these Cd sources by using isotopic signatures in this region. Isotopic variability between these two atmospheric Cd sources may be identified in other areas, and thus warrants further investigation. Regardless, these data provide important initial constraints on the isotope composition of atmospheric Cd inputs to the ocean.
Highlights
Variations in stable isotope composition have recently been employed to study the environmental cycling of Cd, in the ocean
Crustal enrichment factors (EFcrust) are used to assess the relative proportions of the trace metals derived from mineral dust and anthropogenic sources in the aerosols and are calculated by normalizing the trace metal/Al ratio of the aerosol samples (X/Alsample) to that of the upper continental crust (X/Alucc) (equation (2))
Normalization using other elements primarily associated with mineral dust (Ti, Mn, Fe, Sc, and Th) for the calculation of EFcrust values yields results that agree within a factor of 2, compared to those calculated with Al (Figure S1 and Table S5 in the supporting information)
Summary
Variations in stable isotope composition have recently been employed to study the environmental cycling of Cd, in the ocean. Variations in Cd isotope compositions are potentially a useful tool for distinguishing regions where external atmospheric inputs provide important contributions to surface water Cd inventories. Such regions will be prone to perturbation by anthropogenic Cd emissions. Shiel et al [2012, 2013] interpreted Cd isotope data for marine bivalves in the context of anthropogenic and natural Cd sources to coastal waters Despite these important potential applications, the Cd isotope composition of atmospheric aerosols has yet to be thoroughly investigated. The sample set is well suited for the investigation of the isotope compositions of these two important atmospheric Cd sources
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
