Abstract：
The occurrence of microplastics (MPs) was investigated in the Arvand River (Iran). The Arvand River (200 Km) is a major water body that flows through land with diverse use and it meets the Persian Gulf. This study constitutes the first assessment of MP pollution (prevalence and physico-chemical characteristics) in the Arvand river, both in the sediment and in the water. MP monitoring has been carried out in 24 stations located along the river. The MP pollution found ranged between 1 and 291 items·L-1 and 70 to 15,620 items·kg-1 (dw), in water and sediment, respectively. The majority of MPs were fibres, black/grey and yellow/orange in colour, and mainly 250-500 μm and >1000 μm in size. Polyethylene terephthalate (PET), polypropylene (PP), nylon (NYL), high-density polyethylene (HDPE), and polystyrene (PS) were found in sediment samples. All these polymers, except HDPE, were also identified in the water samples. PET and PP were dominant in the water samples; whereas PET and PS were the most abundant in the sediments. The vicinity of urban wastewater effluents could be behind MP pollution in both water and sediments. Significant differences (p < 0.05) of MP concentrations were affected by different land uses when comparing MP levels in undisturbed natural area with urban areas. A strong correlation between MP fibres and fragments found with PCA biplots revealed their similar distribution in water. In the sediment samples, fibre and fragment MP particles were significantly correlated with colloidal particles (e.g., clay and organic matter) suggesting a relevant role of colloidal particles in the aquatic ecosystem of the Arvand River in transporting MPs. This study contributes to the better understanding of the presence of MP in major rivers, which are systems that have been scarcely investigated for this type of pollution, and it can inform interventions to reduce MP inputs to the river and sea.
摘要：
在Arvand河（伊朗）调查了微塑料（MP）的发生。Arvand河（200公里）是一个主要的水体，流经土地，用途多样，与波斯湾相遇。这项研究构成了对Arvand河中MP污染（患病率和物理化学特征）的首次评估，在沉积物和水中。沿河的24个站点进行了MP监测。发现的MP污染范围为1至291项·L-1和70至15,620项·kg-1（dw），在水和沉积物中，分别。大多数议员是纤维，黑色/灰色和黄色/橙色，主要是250-500μm和>1000μm。聚对苯二甲酸乙二醇酯(PET),聚丙烯（PP），尼龙(NYL),高密度聚乙烯(HDPE),在沉积物样品中发现了聚苯乙烯（PS）。所有这些聚合物，除了HDPE，在水样中也被发现。PET和PP在水样中占主导地位；而PET和PS在沉积物中含量最高。城市废水废水附近可能是水和沉积物中MP污染的背后。当比较未受干扰的自然区域与城市区域的MP水平时，MP浓度的显着差异（p<0.05）受不同土地利用的影响。MP纤维与PCA双曲线发现的碎片之间的强相关性表明它们在水中的分布相似。在沉积物样本中,纤维和碎片MP颗粒与胶体颗粒显著相关(例如，粘土和有机物）表明胶体颗粒在Arvand河的水生生态系统中在运输MPs中的相关作用。这项研究有助于更好地了解MP在主要河流中的存在，这些系统很少针对这种类型的污染进行研究，它可以为干预措施提供信息，以减少对河流和海洋的MP输入。
