Nontargeted LC/ESI-HRMS Detection of Polyhalogenated Compounds in Marine Mammals Stranded on French Atlantic Coasts

• Published in: ACS ES&T water Vol. 1; no. 2; pp. 309 - 318
• Main Authors: Cariou, Ronan, Méndez-Fernandez, Paula, Hutinet, Sébastien, Guitton, Yann, Caurant, Florence, Le Bizec, Bruno, Spitz, Jérôme, Vetter, Walter, Dervilly, Gaud
• Format: Journal Article
• Language: English
• Published: American Chemical Society 12.02.2021
• Subjects: Environmental Sciences; halogenated natural product; heptachloro-1,2′-bipyrrole; environmental contaminant; halogenated organic compounds; nontargeted screening; marine top predator; heptachloro-1; 2′-bipyrrole
• ISSN: 2690-0637; 2690-0637
• DOI: 10.1021/acsestwater.0c00091

To date, nontargeted analysis (NTA) of halogenated organic compounds in biota has mostly been performed using GC/MS-based instruments. We intended to broaden the spectrum of physicochemical properties of amenable substances by taking advantage of liquid chromatography–high-resolution mass spectrometry coupling paired with an electrospray ionization source. Thus, a NTA strategy was applied to a set of 12 blubber samples belonging to five marine mammal sentinel species stranded on the French Atlantic coasts. It involved specific postacquisition data interpretation using open-source software HaloSeeker 1.0 for annotating chemical formulas. A total of 135 distinct unequivocal molecular formulas were assigned to 466 polyhalogenated ion clusters of interest. The most intense representative ions were identified as bioaccumulative heptachloro-1,2′-bipyrrole (Cl7-BP), α-hexabromocyclododecane, and (1R,2S,4R,5R,1′E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2′-chloroethenyl)-5-methylcyclohexane (MHC-1) in the weight range of micrograms per gram of lipids. To the best of our knowledge, this is the first time that Cl7-BP, the most intense signal observed, is reported in biota. A dozen other compound families will require further in-depth work to gain structural information.