Imperial College London
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Professor Mark Rehkämper

Faculty of Engineering, Department of Earth Science & Engineering

Professor of Isotope Geochemistry
 
 
 
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Contact

 

markrehk Website

 
 
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Location

 

451Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Barraza:2019:10.1039/c9ra05516a,
author = {Barraza, F and Moore, R and Rehkamper, M and Schreck, E and Lefeuvre, G and Kreissig, K and Coles, B and Maurice, L},
doi = {10.1039/c9ra05516a},
journal = {RSC Advances: an international journal to further the chemical sciences},
pages = {34011--34022},
title = {Cadmium isotope fractionation in soil-cacao systems of Ecuador: a pilot field study},
url = {http://dx.doi.org/10.1039/c9ra05516a},
volume = {9},
year = {2019}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The often high Cd concentrations of cacao beans are a serious concern for producers in Latin America due to the implementation of stricter Cd limits for cocoa products by the European Union in 2019. This is the first investigation to employ coupled Cd isotope and concentration measurements to study soil – cacao systems. Analyses were carried out for 29 samples of soils, soil amendments and cacao tree organs from organic farms in Ecuador that harvest three distinct cacao cultivars. The majority of soils from 0–80 cm depth have very similar δ114/110Cd of about −0.1‰ to 0‰. Two 0–5 cm topsoils, however, have high Cd concentrations coupled with heavy Cd isotope compositions of δ114/110Cd ≈ 0.2%, possibly indicating Cd additions from the tree litter used as organic fertilizer. Whilst cacao leaves, pods and beans are ubiquitously enriched in Cd relative to soils there are distinct Cd isotope signatures. The leaves and pods are isotopically heavier than the soils, with similar Δ114/110Cdleaf–soil values of 0.22 ± 0.07‰ to 0.41 ± 0.09‰. In contrast, the data reveal differences in Δ114/110Cdbean–leaf that may be linked to distinct cacao cultivars. In detail, Δ114/110Cdbean–leaf values of −0.34‰ to −0.40‰ were obtained for Nacional cacao from two farms, whilst CCN-51 hybrid cacao from a third farm showed no fractionation within error (−0.08 ± 0.13‰). As such, further work to investigate whether Cd isotopes are indeed useful for tracing sources of Cd enrichments in soils and to inform genetic efforts to reduce the Cd burden of cocoa is indicated.
AU  - Barraza,F
AU  - Moore,R
AU  - Rehkamper,M
AU  - Schreck,E
AU  - Lefeuvre,G
AU  - Kreissig,K
AU  - Coles,B
AU  - Maurice,L
DO  - 10.1039/c9ra05516a
EP  - 34022
PY  - 2019///
SN  - 2046-2069
SP  - 34011
TI  - Cadmium isotope fractionation in soil-cacao systems of Ecuador: a pilot field study
T2  - RSC Advances: an international journal to further the chemical sciences
UR  - http://dx.doi.org/10.1039/c9ra05516a
UR  - http://hdl.handle.net/10044/1/74538
VL  - 9
ER  -
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