Mercury Stable Isotopes Discriminate Different Populations of European Seabass and Trace Potential Hg Sources around Europe

Cransveld, Alice; Amouroux, David; Tessier, Emmanuel; Koutrakis, E. T.; Öztürk, Ayaka Amaha; Bettoso, Nicola; Mieiro, C.L.; Bérail, Sylvain; Barré, Julien; Sturaro, Nicolas; Schnitzler, Joseph; Das, Krishna

doi:10.1021/acs.est.7b01307

Cited by 31 publications

(48 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…δ 202 Hg) and mass-independent (MIF, e.g. Δ 199 Hg) fractionation enables the quantification of processes and the identification of sources and pathways of Hg in the environment 27 , including marine ecosystems 25,26,28,29 . MDF of Hg isotopes occurs during many physical, chemical or biological processes [30][31][32][33] .…”

Section: Tocart-graphical Abstract 1 Introductionmentioning

confidence: 99%

Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches

Renedo

Amouroux

Albert

et al. 2020

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

Despite the limited direct anthropogenic mercury (Hg) inputs in the circumpolar Arctic, elevated concentrations of methylmercury (MeHg) are accumulated in Arctic marine biota. However, the MeHg production and bioaccumulation pathways in these ecosystems are not completely unravelled. We measured Hg concentrations and stable isotope ratios of Hg, carbon and nitrogen in feathers and blood of geolocator-tracked little auk Alle alle from five Arctic breeding colonies. The wide-range spatial mobility and tissue-specific Hg integration times of this planktivorous seabird allowed the exploration of their spatial (wintering quarters/breeding grounds) and seasonal (non-breeding/breeding periods) MeHg exposure. An east-to-west increase of head feather Hg concentrations (1.74-3.48 µg•g-1) was accompanied by significant spatial trends of Hg isotope (particularly Δ 199 Hg: 0.96 to 1.13‰) and carbon isotope (ẟ 13 C:-20.6 to-19.4‰) ratios. These trends suggest distinct mixing/proportion of MeHg sources between western North Atlantic and eastern Arctic regions. Higher Δ 199 Hg values (+0.4‰) in northern colonies indicate an accumulation of more photochemically impacted MeHg, supporting shallow MeHg production and bioaccumulation in High Arctic waters. The combination of seabird tissue isotopic analysis and spatial-tracking helps tracing the MeHg sources at various spatiotemporal scales.

show abstract

Section: Tocart-graphical Abstract 1 Introductionmentioning

confidence: 99%

Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches

Renedo

Amouroux

Albert

et al. 2020

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Since consumers are enriched in 15 N over their food, δ 15 N values indicate the trophic position of consumers within a given trophic web, thus allowing making interpretations about trophic relationships in ecological studies 45 . Thus, we used δ 13 C and δ 15 N values to help explaining the potential variations in Hg stable isotopes in penguins and to trace the origin, trophic transfer and bioaccumulation processes of Hg in marine food webs, as it was previously demonstrated in fish 41 , 42 , 44 , 46 .…”

Section: Introductionmentioning

confidence: 99%

Identification of sources and bioaccumulation pathways of MeHg in subantarctic penguins: a stable isotopic investigation

Renedo¹,

Amouroux²,

Pedrero³

et al. 2018

Sci Rep

Self Cite

View full text Add to dashboard Cite

Seabirds are widely used as bioindicators of mercury (Hg) contamination in marine ecosystems and the investigation of their foraging strategies is of key importance to better understand methylmercury (MeHg) exposure pathways and environmental sources within the different ecosystems. Here we report stable isotopic composition for both Hg mass-dependent (e.g. δ202Hg) and mass-independent (e.g. Δ199Hg) fractionation (proxies of Hg sources and transformations), carbon (δ13C, proxy of foraging habitat) and nitrogen (δ15N, proxy of trophic position) in blood of four species of sympatric penguins breeding at the subantarctic Crozet Islands (Southern Indian Ocean). Penguins have species-specific foraging strategies, from coastal to oceanic waters and from benthic to pelagic dives, and feed on different prey. A progressive increase to heavier Hg isotopic composition (δ202Hg and Δ199Hg, respectively) was observed from benthic (1.45 ± 0.12 and 1.41 ± 0.06‰) to epipelagic (1.93 ± 0.18 and 1.77 ± 0.13‰) penguins, indicating a benthic-pelagic gradient of MeHg sources close to Crozet Islands. The relative variations of MeHg concentration, δ202Hg and Δ199Hg with pelagic penguins feeding in Polar Front circumpolar waters (1.66 ± 0.11 and 1.54 ± 0.06‰) support that different MeHg sources occur at large scales in Southern Ocean deep waters.

show abstract

“…Detailed description of analytical procedures has been published elsewhere (Cransveld et al, 2017). Briefly, THg concentrations (expressed in ng g −1 dry weight, dw) were measured via atomic absorbance spectrometry (AAS) with a DMA-80 Milestone.…”

Section: Mercury Speciation and Isotopic Compositionmentioning

confidence: 99%

“…Since methylation and demethylation cause fractionation of Hg isotopes (Bergquist and Blum, 2007), speciation and isotopy of Hg should be considered jointly. Through the comparison of Hg mass-dependent and independent isotopic fractionation between muscle and liver, we showed how several subpopulations of seabass around Europe all seem to present in vivo demethylation processes (Cransveld et al, 2017;Pinzone et al, 2021). To be able to link Hg contamination sources to Hg found in biota, it is fundamental to determine whether and how δ 202 Hg and Δ 199 Hg values are changed by internal processes in fish, and to what extent.…”

Section: Introductionmentioning

confidence: 99%

Dynamics of Dietary Mercury Determined by Mercury Speciation and Isotopic Composition in Dicentrarchus labrax

Pinzone

Cransveld

Boeck

et al. 2022

Front. Environ. Chem.

Self Cite

View full text Add to dashboard Cite

Seafood has a great ecological and nutritional value for human and wildlife communities. However, accumulation of mercury (Hg) in fish is a concern to animal and human health. There is a crucial need to understand Hg speciation in marine organisms through controlled feeding experiments. This study represents a first assessment of the biological processes that may influence Hg bioaccumulation and dynamics in a marine predatory fish. We conducted a feeding experiment to investigate the dynamics of MeHg and iHg, as well as Hg isotopes in the liver and muscles of captive juvenile seabass (Dicentrarchus labrax). Three groups of juvenile seabass were fed in captivity during 3 weeks of acclimatization and 6 weeks of experiment. Each group was fed with pellets containing environmentally relevant MeHg concentrations (Control, 200 and 500 ng g−1 dw). We monitored the evolution of MeHg and iHg concentrations as well as Hg isotopic values in liver and muscle. We determined Hg dynamics with respect to the contamination level in the fish diet. Muscle δ202Hg and Δ199Hg turnover rates ranged between 33 and 14 days (Low diet) to 5 and 9 days (Mod diet). Liver δ202Hg and Δ199Hg turnover rates ranged between 3 and 7 days (Low diet) to 3 and 2 days (Mod diet), respectively. Hg species concentrations and δ202Hg varied over time between diet groups and tissues, showing the occurrence of internal mass-dependent fractionation (MDF). No significant intra-tissue and temporal Hg mass-independent fractionation (MIF) was observed. The results of our experiment are strongly in favor of the existence of MeHg demethylation in a coastal predatory fish exposed to low to moderate concentrations of environmental Hg. The decrease over time of δ202Hg in muscle of seabass from the most contaminated diet was accompanied by a temporal increase in iHg, pointing to possible Hg detoxification processes occurring in this tissue when dietary Hg exposure is high. The absence of Hg MDF and different turnover between muscle and liver in seabass exposed to 500 ng Hg g−1 confirmed that Hg speciation and bioaccumulation in juvenile fish are controlled by Hg levels and speciation in their diet.

show abstract

Mercury Stable Isotopes Discriminate Different Populations of European Seabass and Trace Potential Hg Sources around Europe

Cited by 31 publications

References 70 publications

Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches

Contrasting Spatial and Seasonal Trends of Methylmercury Exposure Pathways of Arctic Seabirds: Combination of Large-Scale Tracking and Stable Isotopic Approaches

Identification of sources and bioaccumulation pathways of MeHg in subantarctic penguins: a stable isotopic investigation

Dynamics of Dietary Mercury Determined by Mercury Speciation and Isotopic Composition in Dicentrarchus labrax

Contact Info

Product

Resources

About