Nontargeted comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry method and software for inventorying persistent and bioaccumulative contaminants in marine environments.

Analytical methods for contaminant monitoring are generally targeted; i.e., they measure defined lists of compounds.

δ¹⁵N enrichment suggests possible source for halogenated 1'-methyl-1,2'-bipyrroles (MBPs).

Polyhalogenated 1'-methyl-1,2'-bipyrroles are natural products that biomagnify into upper trophic levels of marine food webs. Here we demonstrate that they are unusually enriched in (15)N (δ(15)N from +19.3‰ to +28.

Marine natural products, the halogenated 1'-methyl-1,2'-bipyrroles, biomagnify in a northwestern Atlantic food web.

Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are putative marine natural products that accumulate in marine mammal blubber in similar concentrations and patterns to biomagnifying organic pollutants. Here we measure concentrations of MBPs and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in 40 samples composed of eight fish species, two squid species, and six species of marine mammals. To determine their trophic positions and to further investigate influence of prey preference, we also measured the stable carbon and nitrogen isotopic compositions of all samples.

Capabilities of direct sample introduction--comprehensive two-dimensional gas chromatography--time-of-flight mass spectrometry to analyze organic chemicals of interest in fish oils.

Most analytical methods for persistent organic pollutants (POPs) focus on individual groups of targeted analytes. Therefore, analysis of multiple classes of POPs typically entails several sample preparations, fractionations, and injections, whereas other chemicals of possible interest are neglected or lost. To analyze a wider scope of organic contaminants in fish oil, we developed an approach to combine the analysis of targeted and untargeted chemicals using an automated direct sample introduction (DSI) and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC x GC/ ToF-MS).

Simultaneous quantitation of multiple classes of organohalogen compounds in fish oils with direct sample introduction comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry.

We successfully optimized an analytical method using gel permeation chromatography followed by direct sample introduction comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry to quantify multiple groups of targeted persistent organic pollutants and halogenated natural products (HNPs) simultaneously in fish oil samples. This new method has a wider analytical scope than the traditional approach to use multiple methods to cover each class of compounds. Our analysis revealed that the relatively more volatile and lighter organic compounds, such as polychlorinated biphenyls (PCBs), organochlorine pesticides, and other smaller organohalogen compounds, were still present in two brands of "PCB-free" cod liver oils, albeit at much lower levels than in an untreated commercial sample.

Distribution patterns suggest biomagnification of halogenated 1'-methyl-1,2'-bipyrroles (MBPs).

The halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are a suite of marine natural products that have been detected in marine mammals worldwide. Although their concentrations are similar to persistent organic pollutants that biomagnify, such as 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), it is notyet clearthat these natural products also biomagnify. Here we analyze MBPs and CB-153 isolated from the blubber and liver of marine mammals stranded on the eastern coast of Massachusetts.