Fire and Oil Led to Complex Mixtures of PAHs on Burnt and Unburnt Plastic during the M/V X-Press Pearl Disaster

Bryan D James; Christopher M Reddy; Mark E Hahn; Robert K Nelson; Asha de Vos; Lihini I Aluwihare; Terry L Wade; Anthony H Knap; Gopal Bera

doi:10.1021/acsenvironau.3c00011

Fire and Oil Led to Complex Mixtures of PAHs on Burnt and Unburnt Plastic during the M/V X-Press Pearl Disaster

ACS Environ Au. 2023 Jul 12;3(5):319-335. doi: 10.1021/acsenvironau.3c00011. eCollection 2023 Sep 20.

Authors

Bryan D James^{1

2}, Christopher M Reddy¹, Mark E Hahn², Robert K Nelson¹, Asha de Vos^{3

4}, Lihini I Aluwihare⁵, Terry L Wade^{6

7}, Anthony H Knap^{6

7

8}, Gopal Bera⁶

Affiliations

¹ Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, United States.
² Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, United States.
³ Oceanswell, 9 Park Gardens, Colombo 00500, Sri Lanka.
⁴ The Oceans Institute, University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia.
⁵ Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, United States.
⁶ Geochemical and Environmental Research Group, Texas A&M University, College Station, Texas 77845, United States.
⁷ Department of Oceanography, Texas A&M University, College Station, Texas 77843, United States.
⁸ Department of Ocean Engineering, Texas A&M University, College Station, Texas 77843, United States.

Abstract

In May 2021, the M/V X-Press Pearl container ship burned for 2 weeks, leading to the largest maritime spill of resin pellets (nurdles). The disaster was exacerbated by the leakage of other cargo and the ship's underway fuel. This disaster affords the unique opportunity to study a time-stamped, geolocated release of plastic under real-world conditions. Field samples collected from beaches in Sri Lanka nearest to the ship comprised nurdles exposed to heat and combustion, burnt plastic pieces (pyroplastic), and oil-plastic agglomerates (petroplastic). An unresolved question is whether the 1600+ tons of spilled and recovered plastic should be considered hazardous waste. Due to the known formation and toxicity of combustion-derived polycyclic aromatic hydrocarbons (PAHs), we measured 20 parent and 21 alkylated PAHs associated with several types of spilled plastic. The maximum PAH content of the sampled pyroplastic had the greatest amount of PAHs recorded for marine plastic debris (199,000 ng/g). In contrast, the sampled unburnt white nurdles had two orders of magnitude less PAH content. The PAH composition varied between the types of spilled plastic and presented features typical of and conflicting with petrogenic and pyrogenic sources. Nevertheless, specific markers and compositional changes for burning plastics were identified, revealing that the fire was the main source of PAHs. Eight months after the spill, the PAH contents of sampled stray nurdles and pyroplastic were reduced by more than 50%. Due to their PAH content exceeding levels allowable for plastic consumer goods, classifying burnt plastic as hazardous waste may be warranted. Following a largely successful cleanup, we recommend that the Sri Lankans re-evaluate the identification, handling, and disposal of the plastic debris collected from beaches and the potential exposure of responders and the public to PAHs from handling it. The maritime disaster underscores pyroplastic as a type of plastic pollution that has yet to be fully explored, despite the pervasiveness of intentional and unintentional burning of plastic globally.