Identification of Microplastics in Beach Sediments of Turtles Nesting Ground in Terengganu
Aina Arifah Khalid (a,b), Maisarah Jaafar (a,b*), Tuan Nurul Sabiqah Tuan Anuar (a,b), Yusuf Shuaib Ibrahim (a.b)

a) Microplastic Research Interest Group (MRIG), Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, MALAYSIA
b) Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
* maisarah[at]umt.edu.my

Abstract

Microplastics on beaches have the potential to alter the composition of shoreline sand, which could affect turtle incubation habitats. Thus, the aim of this study was to determine the abundance of microplastics in three different nesting grounds for green and hawksbill turtles in Terengganu, Malaysia, namely Chagar Hutang, Ma^ Daerah, and Setiu. The sediment samples were collected from a depth of 0-70 cm (with a depth interval of 10 cm) and chemically extracted using a modified WESTPEC method before being manually sorted using a stereo microscope. The abundance of microplastic in turtle nests was consistently found higher at 60-70 cm depth for all locations, with a range of abundance following the trend- Ma^ Daerah (792.5-1110.63 items/kg) \geq Setiu (602.50-763.13 items/kg) \geq Chagar Hutang (535.65-569.38 items/kg). The main shape of microplastics is fibre and fragment, with black being the dominant color (41.41%) and orange being the least (0.17%). Polymers such as Polyacrylamide, Polytetrafluorethylene, Ethylene vinyl alcohol, Phenol formaldehyde , Poly(vinyl alcohol), and Bisphenol A were identified under \muFTIR, which could be linked to human anthropogenic activities such as fishing and local human activities. Scanning electron microscope images of the microplastic surface show pit holes, cracks, and small dirt particles, indicating that the plastic particles have weathered and possibility for pollutants attachment. The findings from this study could provide a baseline data for future research associated with microplastic pollution in sea turtle nesting habitats, allowing for better protection of these endangered species in Malaysia.

Keywords: microplastic, nesting turtle, polymers, sediment, South China Sea

Topic: Aquatic Pollution and Ecotoxicology