我国东部沿海水生食物网和海产品物流中短链氯化石蜡污染源解析及其健康风险

Given the rapid economic growth in the eastern seaboard of China, the coastal waters as the largest fishery of China, have been suffering from severe environmental pollution. The ocean is one of the major sinks of persistent organic pollutants (POPs). After entering into the sea, POPs can bioaccumulate and biomagnify through the marine food web, posing exposure risks to ecological environment and human health. This project will collect some commercial seafood in the main fishing ground of the east coast of China, and examine the levels of short chain chlorinated paraffins (SCCPs), a new POP. Numerical modeling will be performed to elucidate the environmental behavior and cycling of SCCPs, including the primary pathways of SCCPs entering the marine environment, contamination to the sea water and sediment, bioaccumulation through the marine food chain. The factors that may influence the SCCPs environmental fate and cycling in the marine environment, including emission, environmental parameters, and physicochemical properties will be investigated. The sources of SCCPs in the marine environment and web food will be identified. To examine the potential human health exposure risks to SCCPs via consumption of seafood through the seafood trade, the trade information from the origin to destination of the two primary commercial seafood: shrimp and ribbon fish will be collected. Shrimp is a bentonic organism living in the bottom of the marine food web, and the ribbon fish is a top predator in the marine food web in the east coast sea waters of China. By simulating the exposure risks embodied in the seafood trade, the human health risk induced by ingesting the seafood contaminated by SCCPs from the east coast can be assessed quantitatively. The results will provide new insights into protecting the ecosystem and ensuring safety of marine food of coastal waters in east China.

东部沿海海域作为我国主要渔场分布地，因周边地区快速的经济发展而遭受了严重的环境污染。海洋是持久性有机污染物（POPs）的最终归宿之一，POPs进入海洋环境后会沿食物链累积和放大，对海洋生态环境和人体健康造成危害。本研究拟以新型POPs短链氯化石蜡（SCCPs）为研究对象，选取东部沿海主要渔场集散地，采集分析主要海产品中SCCPs浓度；通过数值模拟阐明SCCPs入海、多介质环境行为及生物累积和放大特征，明确影响这些行为和过程的源排放、环境参数及理化性质等主控因子，识别水生环境和食物网中SCCPs的来源；以位于水生食物链底层的底栖生物虾和食物链上层的带鱼为例，调查分析东部沿海这两种海产品从生产到消费的物流信息；利用模拟和观测的两种海产品中SCCPs浓度，评估我国居民因食用东部沿海SCCPs污染的海产品导致的健康风险。该研究可为决策部门保护我国东部沿海海洋生态环境和保障海洋食物安全提供科技支撑。

该项目以新型POPs短链氯化石蜡（SCCPs）为研究对象，选取我国东部沿海主要渔场集散地，采集分析主要海鱼带鱼中SCCPs浓度；更新建立了我国2008-2021年SCCPs大气网格化排放清单，并以此作为输入数据，利用耦合多介质交换的大气迁移模型，模拟了经大气迁移、干湿沉降、气-土交换、气-水交换、水-底泥交换等行为过程后，东部沿海水体和底泥中SCCPs空间分布；基于海洋食物网模型，结合东部沿海带鱼空间捕捞量数据，模拟东部沿海带鱼中SCCPs的浓度水平；基于贸易引力模型估算我国省际间带鱼贸易量，结合食品区块链溯源技术，利用模拟和观测的带鱼中SCCPs浓度，评估我国居民因食用东部沿海SCCPs污染的带鱼导致的健康风险。主要研究结果如下：. （1）基于观测的我国东部沿海带鱼中SCCPs浓度为11.14-105.2ng/g ww，平均为32.86ng/g ww；空间呈现出东海＞渤海＞黄海＞南海的趋势；SCCPs主要以C11和C12同族体为主，其相对丰度分别为35.34％和30.44％。.（2）我国2021年SCCPs大气总排放量为1323吨，其主要分布在京津、长三角、珠三角、山东半岛等地区。另外，SCCPs排放主要集中在作为添加剂在金属切削液的使用过程（47.3%）、氯化石蜡生产过程（40.3%）和作为增塑剂使用过程的排放（9.1%）。.（3）我国东部海域海水中SCCPs平均浓度为 21.0（四分位范围（IR）：9.5-26.4）ng/L，沉积物浓度为 27.3（IR：17.3-31）ng/g ww。高污染主要出现在在山东、江苏、浙江和珠江三角洲的河口及海岸带地区。.（4）海洋食物网模拟结果显示，我国东部沿海的带鱼体内SCCPs浓度为11.5（IR：2.4-13 ng/g ww），空间分布与观测结果一致，但是整体上较观测结果偏低。.（5）我国人群食用带鱼的平均SCCPs暴露量为1.01 ng kg-1 day-1。不同产地带鱼差异显著，食用产于天津（17.9）、莱州湾（16.68）上海（6.07）沿海带鱼导致更高的暴露量。总体上，我国居民因摄入SCCPs污染带鱼导致的暴露量低于每日最高可接受暴露水平。.（6）我国沿海带鱼贸易导致海域污染较严重的江苏、上海、河北和浙江地区的人群 SCCPs 暴露量下降，而导致海域污染较轻的广西、辽宁、福建和海南省的人群暴露量增加。