Microplastics As Carrier Of Pahs Released From Oil Spills: Measuring Ingestion And Bioaccumulation Rates In Copepods

• Main Author: Desai, Manasi
• Format: Text
• Language: English
• Published: Open Works 2022
• Subjects: Environmental Studies; Life Sciences; Indian; Calanus finmarchicus; Copepods
• Online Access: https://openworks.wooster.edu/independentstudy/9847; https://openworks.wooster.edu/cgi/viewcontent.cgi?article=12760&context=independentstudy

Microplastics (MP; plastics < 5mm) are a growing problem in the marine environment due to a large influx of plastics entering the marine environment through rivers, wastewater and litter from land. MP are known to adsorb nonpolar compounds in the water including polycyclic aromatic hydrocarbons (PAHs) released from oil spills. In this study, I quantified the ingestion rates of a marine copepod (Calanus finmarchicus) on clean polystyrene MP beads (12 um) and phenanthrene loaded MP beads (0.8 pg PAH pellet -1). I measured the phenanthrene load in copepods ingesting phenanthrene sorbed MPs and copepods exposed to phenanthrene only to measure the role of MP as a vector for PAHs into marine food webs. Additionally, I examined the fecal pellets to check the presence of MPs and if phenanthrene was still adsorbed to them. The results showed that microplastics do not act as vectors as there was no significant difference between the body load of phenanthrene in copepods from ingestion of PAH sorbed MPs and the body load from passive uptake of phenanthrene in solution. Copepods ate significantly lower phenanthrene loaded MP (1.81 x 104 beads cop-1 day-1) than microplastics only (2.67 x 104 beads cop-1 day-1) suggesting that copepods can reject particles based on chemical content. Accumulation of phenanthrene within the copepods (GC-MS analysis) showed individual copepods can accumulate between 3.48 to 4.11 ng of PAH which potentially can biomagnify in the marine food web upon predation. Fecal pellet analysis showed that an average of 2013 MP beads are present with a mean phenanthrene load of 0.15 pg bead-1. For the social science research, I conducted a literature review examining the current Indian plastic waste management strategies, legislations and its implementation. My results find that the Indian government over the years has progressively enacted and amended its policies to try to keep pace with the issue of plastic pollution. However, key challenges in the implementation such as poor enforcement, inadequate ...