ABSTRACT

Accumulation of microplastic in the marine environment is of great concern and has been considered to be a growing problem in the coastal sediments of Bangladesh. This research represents the large-scale abundance, characterization of microplastic contamination, and its type of polymer in the beach sediment of Cox’s Bazar. To understand the potential impacts associated with microplastic pollution in Cox’s Bazar coastal area, quantification, identification, and spatial distribution of the types of microplastic and polymer were done from the collected samples of Cox’s Bazar coastal regions. All sediments analyzed through visual and Scanning Electron Microscope (SEM) identification contained microplastic particles (<5 mm). The majority of the detected microplastics were found to be fibrous (< 1 mm), which accounted for more than 70% of the total microplastics. Through the use of Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, the study identified the type of polymer present. Evaluation of qualitative measurements of various polymer types has been done, including rayon, nylon, polyethylene (PE), polystyrene (PS), polypropylene (PP), polyurethane (PU), alkyd, epoxy, and the polyethylene–polypropylene copolymer (PE + PP). Quantitative analysis performed and illustrated using analytical tools to document the amount of microplastic (particles 100 g⁻¹). Rayon, nylon, and polyethylene are the most abundant polymers throughout the sampled regions whereas polypropylene which were found to be the least abundant. Microplastic concentration is highest in the regions of Laboni point (111) and Kolatoli (97) in the Cox’s Bazar beach. On the contrary, Himchori (6) and Bardeil (5) areas show the lowest abundance of microplastic that can be correlated with the growth of tourism centered urbanization. The findings of this work can help identify potential sources of microplastics that can be utilized to improve the coastal environment and provide valuable clues to coastal zone management in Cox’s Bazar regions.

摘要

海洋环境中微塑料的积累备受关注，并被认为是孟加拉国沿海沉积物中日益严重的问题。这项研究代表了考克斯巴扎尔海滩沉积物中微塑料污染的大规模丰度、表征及其聚合物类型。为了了解与 Cox's Bazar 沿海地区微塑料污染相关的潜在影响，对 Cox's Bazar 沿海地区收集的样本进行了微塑料和聚合物类型的量化、识别和空间分布。通过视觉和扫描电子显微镜 (SEM) 鉴定分析的所有沉积物都含有微塑料颗粒 (<5 mm)。大多数检测到的微塑料被发现是纤维状的（< 1 毫米），其中微塑料占总量的70%以上。通过使用衰减全反射-傅里叶变换红外 (ATR-FTIR) 光谱，该研究确定了存在的聚合物类型。已经对各种聚合物类型的定性测量进行了评估，包括人造丝、尼龙、聚乙烯 (PE)、聚苯乙烯 (PS)、聚丙烯 (PP)、聚氨酯 (PU)、醇酸树脂、环氧树脂和聚乙烯-聚丙烯共聚物 (PE +聚丙烯）。使用分析工具进行定量分析并说明微塑料的数量（颗粒 100 g 聚乙烯 (PE)、聚苯乙烯 (PS)、聚丙烯 (PP)、聚氨酯 (PU)、醇酸树脂、环氧树脂和聚乙烯-聚丙烯共聚物 (PE + PP)。使用分析工具进行定量分析并说明微塑料的数量（颗粒 100 g 聚乙烯 (PE)、聚苯乙烯 (PS)、聚丙烯 (PP)、聚氨酯 (PU)、醇酸树脂、环氧树脂和聚乙烯-聚丙烯共聚物 (PE + PP)。使用分析工具进行定量分析并说明微塑料的数量（颗粒 100 g^-1 )。人造丝、尼龙和聚乙烯是整个采样区域中含量最高的聚合物，而聚丙烯含量最低。Cox's Bazar 海滩的 Laboni point (111) 和 Kolatoli (97) 地区的微塑料浓度最高。相反，Himbori (6) 和 Bardeil (5) 地区的微塑料丰度最低，这与以旅游为中心的城市化发展相关。这项工作的结果可以帮助确定可用于改善沿海环境的微塑料的潜在来源，并为考克斯巴扎尔地区的沿海地区管理提供有价值的线索。