Badola Neha, Sobhan Faisal, Chauhan Jaspal Singh
Aquatic Ecology Lab, Department of Himalayan Aquatic Biodiversity, Hemvati Nandan Bahuguna Garhwal University (A Central University), Srinagar-Garhwal, Uttarakhand 246174, India.
Department of Oceanography, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh.
Sci Total Environ. 2023 Nov 25;901:165924. doi: 10.1016/j.scitotenv.2023.165924. Epub 2023 Jul 30.
The River Ganga has been explored for microplastics (MPs) majorly in the lower or middle course, while the upper course from where the river starts its journey remains untouched. This study investigates the occurrence and distribution of MPs in the river environment (water and sediment) and common fishes inhabiting the upper stretch of River Ganga in the Uttarakhand state of India. A volume-reduce method by using sieve filtration was used to take water and sediment samples from the study area while fish samples were collected using net method. The samples underwent alkali digestion, microscopic examination, and chemical analysis using Fourier Transformed Infrared Spectroscopy (FTIR). An average of 118.5 ± 49.65 particles per 1000 L and 131.5 ± 53.60 particles/kg dry weight were found in water and sediment respectively. While in the fishes, Tor tor, Schizothorax richardsonii, Labeo dero and Gara gotyla gotyla MPs were 53.13 ± 63.77, 36.33 ± 22.34, 15.42 ± 9.33 and 12.63 ± 5.93 particles/individual respectively. A positive correlation was observed between the number of MPs in fish and their body length, weight, and gut weight, while no correlation was found between feeding habit and MP accumulation. The majority of MPs detected were fibers ranging from 100 μm to 1 mm in size. Polymer types varied among water, sediment, and fish samples, with polyethylene (PE) predominant in water, polypropylene (PP) dominant in sediment, and polyethylene terephthalate (PET) and polystyrene (PS) most abundant in fish samples.
恒河主要在中下游河段对微塑料（MPs）进行了探索，而这条河流开始其旅程的上游河段仍未被涉足。本研究调查了印度北阿坎德邦恒河上游河段的河流环境（水和沉积物）以及栖息在该河段的常见鱼类中微塑料的存在情况和分布。通过筛网过滤的体积减少法从研究区域采集水和沉积物样本，而鱼类样本则采用网捕法收集。样本经过碱消化、显微镜检查以及使用傅里叶变换红外光谱（FTIR）进行化学分析。在水中平均每1000升发现118.5±49.65个颗粒，在沉积物中平均每千克干重发现131.5±53.60个颗粒。在鱼类中，印度野鲮、宽头裂腹鱼、长背野鲮和吉罗鱼体内的微塑料分别为53.13±63.77、36.33±22.34、15.42±9.33和12.63±5.93个/个体。观察到鱼类体内微塑料数量与其体长、体重和肠重之间呈正相关，而在摄食习性与微塑料积累之间未发现相关性。检测到的大多数微塑料为尺寸在100μm至1mm之间的纤维。聚合物类型在水、沉积物和鱼类样本中各不相同，水中以聚乙烯（PE）为主，沉积物中以聚丙烯（PP）为主，鱼类样本中以聚对苯二甲酸乙二酯（PET）和聚苯乙烯（PS）最为丰富。
