title: Solid-phase microextraction set-up for the analysis of liver volatolome to detect livestock exposure to micropollutants.
abstract: Starting from a critical analysis of a first "proof of concept" study on the utility of the liver volatolome for detecting livestock exposure to environmental micropollutants (Berge et al., 2011), the primary aim of this paper is to improve extraction conditions so as to obtain more representative extracts by using an extraction temperature closer to livestock physiological conditions while minimizing analytical variability and maximizing Volatile Organic Compound (VOC) abundancies. Levers related to extraction conditions and sample preparation were assessed in the light of both abundance and coefficient of variation of 22 candidate VOC markers identified in earlier volatolomic studies. Starting with a CAR/PDMS fiber and a 30min extraction, the reduction of SPME temperature to 40°C resulted in a significant decrease in the area of 14 candidate VOC markers (p<0.05), mainly carbonyls and alcohols but also a reduction in the coefficient of variation for 17 of them. In order to restore VOC abundances and to minimize variability, two approaches dealing with sample preparation were investigated. By increasing sample defrosting time at 4°C from 0 to 24h yielded higher abundances and lower variabilities for 15 and 13 compounds, respectively. Lastly, by using additives favouring the release of VOCs (1.2g of NaCl) the sensitivity of the analysis was improved with a significant increase in VOC abundances of more than 50% for 13 out of the 22 candidate markers. The modified SPME parameters significantly enhanced the abundances while decreasing the analytical variability for most candidate VOC markers. The second step was to validate the ability of the revised SPME protocol to discriminate intentionally contaminated broiler chickens from controls, under case/control animal testing conditions. After verification of the contamination levels of the animals by national reference laboratories, data analysis by a multivariate chemometric method (Common Components and Specific Weights Analysis - ComDim) showed that the liver volatolome could reveal dietary exposure of broilers to a group of environmental pollutants (PCBs), a veterinary treatment (monensin), and a pesticide (deltamethrin), thus confirming the usefulness of this analytical set-up.
authors.affiliation: INRA, UR370 QuaPA, MASS laboratory, Saint-Genès-Champanelle, France; INRA, UMR GENIAL, AgroParisTech, Université Paris-Saclay, Massy, France.
authors.forename: Jihéne
authors.initials: J
authors.lastname: Bouhlel
authors.affiliation: INRA, UR370 QuaPA, MASS laboratory, Saint-Genès-Champanelle, France.
authors.forename: Jérémy
authors.initials: J
authors.lastname: Ratel
authors.affiliation: INRA, UR370 QuaPA, MASS laboratory, Saint-Genès-Champanelle, France.
authors.forename: Said
authors.initials: S
authors.lastname: Abouelkaram
authors.affiliation: INRA, UR370 QuaPA, MASS laboratory, Saint-Genès-Champanelle, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mercier
authors.affiliation: INRA, ITAVI, Centre de Tours, Nouzilly, France.
authors.forename: Angelique
authors.initials: A
authors.lastname: Travel
authors.affiliation: INRA, URA83, Nouzilly, France.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Baéza
authors.affiliation: INRA, URA83, Nouzilly, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Jondreville
authors.affiliation: Oniris, LABERCA, Nantes, France.
authors.forename: Gaud
authors.initials: G
authors.lastname: Dervilly-Pinel
authors.affiliation: Oniris, LABERCA, Nantes, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Marchand
authors.affiliation: Oniris, LABERCA, Nantes, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Le Bizec
authors.affiliation: ANSES, Reference laboratory for veterinary drug residues in food, Fougères, France.
authors.forename: Estelle
authors.initials: E
authors.lastname: Dubreil
authors.affiliation: ANSES, Reference laboratory for veterinary drug residues in food, Fougères, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Mompelat
authors.affiliation: ANSES, Reference laboratory for veterinary drug residues in food, Fougères, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Verdon
authors.affiliation: ANSES, Laboratory for Food Safety, Maisons-Alfort, France.
authors.forename: Chanthadary
authors.initials: C
authors.lastname: Inthavong
authors.affiliation: ANSES, Laboratory for Food Safety, Maisons-Alfort, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Guérin
authors.affiliation: INRA, UMR GENIAL, AgroParisTech, Université Paris-Saclay, Massy, France.
authors.forename: Douglas N
authors.initials: DN
authors.lastname: Rutledge
authors.affiliation: INRA, UR370 QuaPA, MASS laboratory, Saint-Genès-Champanelle, France. Electronic address: erwan.engel@inra.fr.
authors.forename: Erwan
authors.initials: E
authors.lastname: Engel
mesh_terms: D000438:Alcohols / Q000032:analysis; D000818:Animals; D002645:Chickens / Q000378:metabolism; D004785:Environmental Pollutants / Q000032:analysis*; D008099:Liver / Q000737:chemistry*; D058751:Livestock / Q000378:metabolism*; D008985:Monensin / Q000032:analysis; D009570:Nitriles / Q000032:analysis; D010575:Pesticides / Q000032:analysis; D011722:Pyrethrins / Q000032:analysis; D052617:Solid Phase Microextraction / Q000379:methods*; D013696:Temperature; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D000438:Alcohols; D004785:Environmental Pollutants; D009570:Nitriles; D010575:Pesticides; D011722:Pyrethrins; D055549:Volatile Organic Compounds; C017180:decamethrin; D008985:Monensin
keywords: Common components and specific weights analysis; Liver; Micropollutants; SPME; Volatolomics