TY - JOUR
T1 - Accumulation of 13C-labelled phenanthrene in phytoplankton and transfer to corals resolved using cavity ring-down spectroscopy
AU - Ashok, Ananya
AU - Kottuparambil, Sreejith
AU - Høj, Lone
AU - Negri, Andrew P.
AU - Duarte, Carlos M.
AU - Agusti, Susana
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This research was funded by King Abdullah University of Science and Technology (KAUST) through baseline funding to S. Agustí, start-up funding to C.M. Duarte and a center partnership project between the Red Sea Research Center (RSRC) and the Australian Institute of Marine Science (AIMS). This research also benefited from resources of the Core Labs of King Abdullah University of Science and Technology (KAUST). We thank Florita Flores, Diane Brinkman and Biying Wu for their help in conducting the experiments, SeaSim staff at AIMS for providing their expertise and assistance, and Paloma Carrillo de Albornoz for help with Picarro-CRDS analysis.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants in marine ecosystems including threatened and potentially sensitive coral reefs. Lower organisms such as phytoplankton, known to bioconcentrate PAHs, could serve as potential entry points for these chemicals into higher trophic levels. Here, we present a novel method using a 13C-labelled PAH and cavity ring-down spectroscopy (CRDS) to investigate accumulation, uptake rates and trophic transfer of PAHs in corals, which are key organisms to sustain biodiversity in tropical seas. We quantified the accumulation of 13C-phenanthrene in the marine microalga Dunaliella salina, and in the coral Acropora millepora after diffusive uptake from seawater or dietary uptake via labelled D. salina. Additionally, we monitored the photophysiological health of D. salina and A. millepora during phenanthrene exposure by pulse-amplitude modulation (PAM) fluorometry. Dose-dependent accumulation of 13C-phenanthrene in the microalga showed a mean bioconcentration factor (BCF) of 2590 ± 787 L kg−1 dry weight. Corals accumulated phenanthrene from both exposure routes. While uptake of 13C-phenanthrene in corals was faster through aqueous exposure than dietary exposure, passive diffusion showed larger variability between individuals and both routes resulted in accumulation of similar concentrations of phenanthrene. The 13C-PAH labelling and analysis by CRDS proved to be a highly sensitive method. The use of stable isotopic label eliminated additional toxicity and risks by radioactive isotopic-labelling, and CRDS reduced the analytical complexity of PAH (less biomass, no extraction, fast analysis). The simultaneous, precise quantification of both carbon content and 13C/12C ratio (δ13C) enabled accurate determination of 13C-phenanthrene accumulation and uptake rate. This is the first study to provide empirical evidence for accumulation of phenanthrene in a phytoplankton-coral food chain.
AB - Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants in marine ecosystems including threatened and potentially sensitive coral reefs. Lower organisms such as phytoplankton, known to bioconcentrate PAHs, could serve as potential entry points for these chemicals into higher trophic levels. Here, we present a novel method using a 13C-labelled PAH and cavity ring-down spectroscopy (CRDS) to investigate accumulation, uptake rates and trophic transfer of PAHs in corals, which are key organisms to sustain biodiversity in tropical seas. We quantified the accumulation of 13C-phenanthrene in the marine microalga Dunaliella salina, and in the coral Acropora millepora after diffusive uptake from seawater or dietary uptake via labelled D. salina. Additionally, we monitored the photophysiological health of D. salina and A. millepora during phenanthrene exposure by pulse-amplitude modulation (PAM) fluorometry. Dose-dependent accumulation of 13C-phenanthrene in the microalga showed a mean bioconcentration factor (BCF) of 2590 ± 787 L kg−1 dry weight. Corals accumulated phenanthrene from both exposure routes. While uptake of 13C-phenanthrene in corals was faster through aqueous exposure than dietary exposure, passive diffusion showed larger variability between individuals and both routes resulted in accumulation of similar concentrations of phenanthrene. The 13C-PAH labelling and analysis by CRDS proved to be a highly sensitive method. The use of stable isotopic label eliminated additional toxicity and risks by radioactive isotopic-labelling, and CRDS reduced the analytical complexity of PAH (less biomass, no extraction, fast analysis). The simultaneous, precise quantification of both carbon content and 13C/12C ratio (δ13C) enabled accurate determination of 13C-phenanthrene accumulation and uptake rate. This is the first study to provide empirical evidence for accumulation of phenanthrene in a phytoplankton-coral food chain.
UR - http://hdl.handle.net/10754/662449
UR - https://linkinghub.elsevier.com/retrieve/pii/S014765132030350X
UR - http://www.scopus.com/inward/record.url?scp=85082532723&partnerID=8YFLogxK
U2 - 10.1016/j.ecoenv.2020.110511
DO - 10.1016/j.ecoenv.2020.110511
M3 - Article
C2 - 32247239
SN - 1090-2414
VL - 196
SP - 110511
JO - Ecotoxicology and Environmental Safety
JF - Ecotoxicology and Environmental Safety
ER -
