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Papers by Guilhem Caumette

Research paper thumbnail of Analyse de spéciation des métaux dans les produits lourds du pétrole par couplage LC-ICP MS (Chromatographie liquide – Spectromètre de masse à plasma induit)

Research paper thumbnail of Arsenic Speciation in Plankton Organisms from Contaminated Lakes: Transformations at the Base of the Freshwater Food Chain

Environ Sci Technol, 2012

Research paper thumbnail of Transcriptomic responses during early development following arsenic exposure in Western clawed frogs, Silurana tropicalis

Toxicological Sciences, 2015

Arsenic compounds are widespread environmental contaminants and exposure elicits serious health i... more Arsenic compounds are widespread environmental contaminants and exposure elicits serious health issues, including early developmental anomalies. Depending on the oxidation state, the intermediates of arsenic metabolism interfere with a range of subcellular events, but the fundamental molecular events that lead to speciation-dependent arsenic toxicity are not fully elucidated. The present study therefore assesses the impact of arsenic exposure on early development by measuring speciation and gene expression profiles in the developing Western clawed frog (Silurana tropicalis) larvae following the environmental relevant 0.5 and 1 ppm arsenate exposure. Using HPLC-ICP-MS, arsenate, dimethylarsenic acid, arsenobetaine, arsenocholine, and tetramethylarsonium ion were detected. Microarray and pathway analyses were utilized to characterize the comprehensive transcriptomic responses to arsenic exposure. Clustering analysis of expression data showed distinct gene expression patterns in arsenate treated groups when compared with the control. Pathway enrichment revealed common biological themes enriched in both treatments, including cell signal transduction, cell survival, and developmental pathways. Moreover, the 0.5 ppm exposure led to the enrichment of pathways and biological processes involved in arsenic intake or efflux, as well as histone remodelling. These compensatory responses are hypothesized to be responsible for maintaining an in-body arsenic level comparable to control animals. With no appreciable changes observed in malformation and mortality between control and exposed larvae, this is the first study to suggest that the underlying transcriptomic regulations related to signal transduction, cell survival, developmental pathways, and histone remodelling may contribute to maintaining ongoing development while coping with the potential arsenic toxicity in S.tropicalis during early development.

Research paper thumbnail of Application of the Canada-Ontario Decision-making Framework for Contaminated Sediments in the Kingston Inner Harbour

Research paper thumbnail of Strategies of Gammarus pulex L. to cope with arsenic — Results from speciation analyses by IC–ICP-MS and XAS micro-mapping

Science of The Total Environment, 2015

Research paper thumbnail of Arsenic(+3) and DNA methyltransferases, and arsenic speciation in tadpole and frog life stages of western clawed frogs (Silurana tropicalis) exposed to arsenate

Metallomics : integrated biometal science, Jan 12, 2015

Western clawed frog (Silurana tropicalis) embryos were exposed to control, low (nominally 0.5 mg ... more Western clawed frog (Silurana tropicalis) embryos were exposed to control, low (nominally 0.5 mg L(-1)) and high (nominally 1 mg L(-1)) arsenate (As(V)) culture water concentrations to investigate the effects of arsenic (As) on different life stages, namely tadpole (Nieuwkoop and Faber stage 56, NF56) and frog stages (NF66). The effects were assessed by measuring arsenic(+3) and DNA methyltransferases (AS3MT and DNMT1), as well as As speciation in the tissues. The As content in frog tissues increased with water As concentration. The As species observed by high performance liquid chromatography - inductively coupled plasma mass spectrometry (HPLC-ICPMS) were mostly inorganic, dimethylarsinic acid (DMA) and trimethylarsine oxide (TMAO). With solid state X-ray absorption near edge structure (XANES) analysis, arsenobetaine/tetramethylarsonium ion were also seen. AS3MT levels decreased upon low As exposure in NF56, rising again to control levels at the high As exposure. In NF66 tissues, ...

Research paper thumbnail of Arsenic cycling in freshwater phytoplankton and zooplankton cultures

Environmental Chemistry, 2014

Research paper thumbnail of Arsenic distribution and speciation in Daphnia pulex

Science of The Total Environment, 2012

Research paper thumbnail of Element speciation analysis of petroleum and related materials

Journal of Analytical Atomic Spectrometry, 2009

Research paper thumbnail of Fractionation and speciation of nickel and vanadium in crude oils by size exclusion chromatography-ICP MS and normal phase HPLC-ICP MS

Journal of Analytical Atomic Spectrometry, 2010

Research paper thumbnail of Monitoring the behaviour and fate of nickel and vanadium complexes during vacuum residue hydrotreatment and fraction separation

Fuel Processing Technology, 2014

Research paper thumbnail of Monitoring the Arsenic and Iodine Exposure of Seaweed-Eating North Ronaldsay Sheep from the Gestational and Suckling Periods to Adulthood by Using Horns as a Dietary Archive

Environmental Science & Technology, 2007

Research paper thumbnail of Arsenic Speciation in Plankton Organisms from Contaminated Lakes: Transformations at the Base of the Freshwater Food Chain

Environmental Science & Technology, 2011

Research paper thumbnail of Sensitivity improvement in ICP MS analysis of fuels and light petroleum matrices using a microflow nebulizer and heated spray chamber sample introduction

Talanta, 2009

Reasons for signal suppression during the analysis of light petroleum matrices by inductively cou... more Reasons for signal suppression during the analysis of light petroleum matrices by inductively coupled plasma mass spectrometry (ICP MS) were examined. A decrease of the ionization efficiency of the plasma was found to be the principal factor responsible for this loss of sensitivity. Consequently, an interface based on a total consumption micronebulizer and a heated spray chamber was constructed to alleviate this problem. A method based on flow-injection ICP MS using this interface was developed for the direct multielement analysis of undiluted fuels (gasoline, kerosene) and gas condensates offering an increase in sensitivity by at least a factor of 3–4 in comparison with the existing setups.

Research paper thumbnail of Analyse de spéciation des métaux dans les produits lourds du pétrole par couplage LC-ICP MS (Chromatographie liquide – Spectromètre de masse à plasma induit)

Research paper thumbnail of Arsenic Speciation in Plankton Organisms from Contaminated Lakes: Transformations at the Base of the Freshwater Food Chain

Environ Sci Technol, 2012

Research paper thumbnail of Transcriptomic responses during early development following arsenic exposure in Western clawed frogs, Silurana tropicalis

Toxicological Sciences, 2015

Arsenic compounds are widespread environmental contaminants and exposure elicits serious health i... more Arsenic compounds are widespread environmental contaminants and exposure elicits serious health issues, including early developmental anomalies. Depending on the oxidation state, the intermediates of arsenic metabolism interfere with a range of subcellular events, but the fundamental molecular events that lead to speciation-dependent arsenic toxicity are not fully elucidated. The present study therefore assesses the impact of arsenic exposure on early development by measuring speciation and gene expression profiles in the developing Western clawed frog (Silurana tropicalis) larvae following the environmental relevant 0.5 and 1 ppm arsenate exposure. Using HPLC-ICP-MS, arsenate, dimethylarsenic acid, arsenobetaine, arsenocholine, and tetramethylarsonium ion were detected. Microarray and pathway analyses were utilized to characterize the comprehensive transcriptomic responses to arsenic exposure. Clustering analysis of expression data showed distinct gene expression patterns in arsenate treated groups when compared with the control. Pathway enrichment revealed common biological themes enriched in both treatments, including cell signal transduction, cell survival, and developmental pathways. Moreover, the 0.5 ppm exposure led to the enrichment of pathways and biological processes involved in arsenic intake or efflux, as well as histone remodelling. These compensatory responses are hypothesized to be responsible for maintaining an in-body arsenic level comparable to control animals. With no appreciable changes observed in malformation and mortality between control and exposed larvae, this is the first study to suggest that the underlying transcriptomic regulations related to signal transduction, cell survival, developmental pathways, and histone remodelling may contribute to maintaining ongoing development while coping with the potential arsenic toxicity in S.tropicalis during early development.

Research paper thumbnail of Application of the Canada-Ontario Decision-making Framework for Contaminated Sediments in the Kingston Inner Harbour

Research paper thumbnail of Strategies of Gammarus pulex L. to cope with arsenic — Results from speciation analyses by IC–ICP-MS and XAS micro-mapping

Science of The Total Environment, 2015

Research paper thumbnail of Arsenic(+3) and DNA methyltransferases, and arsenic speciation in tadpole and frog life stages of western clawed frogs (Silurana tropicalis) exposed to arsenate

Metallomics : integrated biometal science, Jan 12, 2015

Western clawed frog (Silurana tropicalis) embryos were exposed to control, low (nominally 0.5 mg ... more Western clawed frog (Silurana tropicalis) embryos were exposed to control, low (nominally 0.5 mg L(-1)) and high (nominally 1 mg L(-1)) arsenate (As(V)) culture water concentrations to investigate the effects of arsenic (As) on different life stages, namely tadpole (Nieuwkoop and Faber stage 56, NF56) and frog stages (NF66). The effects were assessed by measuring arsenic(+3) and DNA methyltransferases (AS3MT and DNMT1), as well as As speciation in the tissues. The As content in frog tissues increased with water As concentration. The As species observed by high performance liquid chromatography - inductively coupled plasma mass spectrometry (HPLC-ICPMS) were mostly inorganic, dimethylarsinic acid (DMA) and trimethylarsine oxide (TMAO). With solid state X-ray absorption near edge structure (XANES) analysis, arsenobetaine/tetramethylarsonium ion were also seen. AS3MT levels decreased upon low As exposure in NF56, rising again to control levels at the high As exposure. In NF66 tissues, ...

Research paper thumbnail of Arsenic cycling in freshwater phytoplankton and zooplankton cultures

Environmental Chemistry, 2014

Research paper thumbnail of Arsenic distribution and speciation in Daphnia pulex

Science of The Total Environment, 2012

Research paper thumbnail of Element speciation analysis of petroleum and related materials

Journal of Analytical Atomic Spectrometry, 2009

Research paper thumbnail of Fractionation and speciation of nickel and vanadium in crude oils by size exclusion chromatography-ICP MS and normal phase HPLC-ICP MS

Journal of Analytical Atomic Spectrometry, 2010

Research paper thumbnail of Monitoring the behaviour and fate of nickel and vanadium complexes during vacuum residue hydrotreatment and fraction separation

Fuel Processing Technology, 2014

Research paper thumbnail of Monitoring the Arsenic and Iodine Exposure of Seaweed-Eating North Ronaldsay Sheep from the Gestational and Suckling Periods to Adulthood by Using Horns as a Dietary Archive

Environmental Science & Technology, 2007

Research paper thumbnail of Arsenic Speciation in Plankton Organisms from Contaminated Lakes: Transformations at the Base of the Freshwater Food Chain

Environmental Science & Technology, 2011

Research paper thumbnail of Sensitivity improvement in ICP MS analysis of fuels and light petroleum matrices using a microflow nebulizer and heated spray chamber sample introduction

Talanta, 2009

Reasons for signal suppression during the analysis of light petroleum matrices by inductively cou... more Reasons for signal suppression during the analysis of light petroleum matrices by inductively coupled plasma mass spectrometry (ICP MS) were examined. A decrease of the ionization efficiency of the plasma was found to be the principal factor responsible for this loss of sensitivity. Consequently, an interface based on a total consumption micronebulizer and a heated spray chamber was constructed to alleviate this problem. A method based on flow-injection ICP MS using this interface was developed for the direct multielement analysis of undiluted fuels (gasoline, kerosene) and gas condensates offering an increase in sensitivity by at least a factor of 3–4 in comparison with the existing setups.