海南万泉河入海河口微塑料赋存特征及风险评价

Occurrence and Risk Assessment of Microplastics in Estuaries Area of Wanquan River,Hainan

为探索海南万泉河入海河口区的微塑料赋存特征,采用现场调查和实验室分析相结合的方法研究微塑料分布和组成特征,解析其潜在来源,并结合聚合物风险指数法、污染负荷指数法和潜在生态风险指数法评估其生态风险。结果表明:万泉河入海河口微塑料丰度为0.32~0.74个/m^(3),平均丰度为(0.53±0.13)个/m^(3);微塑料成分主要为聚丙烯(PP,34.8%)、聚酯纤维(PES,23.7%)和聚乙烯(PE,20.0%);形状多为片状(58.4%),其次为纤维状(32.3%);颜色呈现出多样化,以半透明(41.6%)和白色(36.8%)为主;粒径以1.0~4.0 mm的微塑料为主,占比为42.2%。特征分析显示,微塑料主要来源于旅游活动、渔业生产和居民生产生活污水,且受风力、海流、径流和海水稀释的影响,微塑料丰度值呈区域分布不均匀现象。与国内外研究相比,万泉河入海河口的表层海水微塑料丰度处于较低污染水平。风险评价结果也表明,该区域微塑料整体污染水平较低,但对于高化学毒性的塑料制品的危害应不容忽视。

To probe the storage characteristics of microplastics in estuaries of Wanquan river,Hainan,the distribution and composition of microplastics were explored by combination of on-site investigation and laboratory analysis.The potential sources were analyzed,and the ecological risks were assessed by the polymer risk index,pollution load index,and potential ecological risk index.Results showed that microplastics abundance in Wanquan river estuaries were ranged from 0.32 to 0.74 ind/m^(3) and the mean value was(0.53±0.13)ind/m^(3).The components of microplastics were polypropylene(PP,34.8%),polyester(PES,23.7%)and polyethylene(PE,20.0%).Microplastics shapes were mostly in the form of fragments(58.4%),followed by fibers(32.3%).While colors displayed a wide variety,with a predominance of translucent(41.6%)and white(36.8%)colors.Size of microplastics were ranged from 1.0 to 4.0 mm,accounting for 42.2%.The characteristic analysis indicated that microplastics primarily originated from tourism activities,fisheries production,and domestic sewage from residents.Furthermore,microplastics abundance exhibited a regional distribution unevenly,which influenced by wind power,ocean currents,runoff,and seawater dilution.Compared with domestic and abroad studies,the surface seawater microplastics in the estuary of Wanquan river were at a relatively low pollution level.The risk assessment results also showed that the overall pollution level of microplastics in this region were low,but control measures should be taken for plastic products with high chemical toxicity.