High Molecular Weight Polycyclic Aromatic Hydrocarbons (PAHs) in Microplastic Samples Collected Following the Sinking of the Container Ship X-Press PearlAnalyzing Microplastics in the Environment
Oral Presentation
Prepared by D. Stevens1, F. Dorman1, C. Reddy2, B. James2, R. Nelson2
1 - Waters Corporation, 34 Maple Street, Mailstop GC, Milford, Massachusetts, 01757, United States
2 - Woods Hole Oceanographic Institution, Fye Lab, 360 Woods Hole Road, Woods Hole, MA, 02543, United States
Contact Information: [email protected]; 508-369-8311
ABSTRACT
While there is a persistent release of microplastics into the global environment through the degradation and weathering of larger plastics, there are also incidents in which plastics already <5um are directly spilled into the environment. One such incident occurred in 2021 due to the on-board fire and subsequent sinking of the container ship M/V X-Press Pearl off the coast of Columbo, Sri Lanka. The over 1600 tons of polyethylene nurdles spilled, obviously, presented one challenge due to the shear size of the problem. Complexity, however, was another important factor. The ship was laden with a variety of chemicals that when combined with a fire, caused by leaking nitric acid containers, created conditions that started the transformation of nurdles even before they entered the water where they are prone to undergo further alteration by absorbing and releasing compounds as they migrate through ocean currents and sediments. Samples collected from nearby beaches span a continuum from relatively intact pellets to aggregated combustion remnants. Chemical characterization of these complex samples is necessary to determine the most appropriate way of disposing of the tons of debris because toxic compound inclusion leads to more onerous, expensive disposal requirements. PAHs were suspected to be among the likely, abundant and complex analyte classes requiring characterization. Routine analysis of PAHs commonly involves GC/MS for analytes in the range of 128 to 302 Da. However, it is known that toxicity of specific PAH conformations increases with increasing molecular weight. Therefore, in this work the focus was on higher molecular weight PAHs, 314 to 424 Da, using GC-APCI and MS/MS. Samples were analyzed on a XevoTM TQ Absolute (Waters Corporation) tandem quadrupole system fitted with the Atmospheric Pressure Gas Chromatography (APGCTM) source. Data for standard reference materials and extracted samples will be presented.
