设施蔬菜生产与食用过程酞酸酯的人体暴露及区域差异研究

With the growth of greenhouse area and amount of greenhouse vegetable consumption in China, the human exposure risk to phthalate esters has increased from greenhouse vegetable production and consumption systems. The exposure parameter is an important key to evaluate this exposure accurately, but most of current studies basically adopted the recommended or reference values to quantify the local exposure levels to phthalate esters. There are large variations in soil properties, greenhouse types, vegetable species grown, behavior of populations in the greenhouse planting area, as well as differing dietary habits of the populations among different regions in China, thus, it is hard to accurately exposure the local exposure levels to phthalate esters by adopting the recommended or reference values. Also, vegetable transportation between regions has been ignored in current studies. In order to solve above problems, we will choose Shaanxi province as object to do the exposure assessment at regional level. We will divide Shaanxi into three regions, involving southern Shaanxi (SS), central Shaanxi (CS), and northern Shaanxi (NS). Firstly, we will respectively select typical greenhouse vegetable production areas in SS, CS, and NS, and get the concentration of phthalate esters in greenhouse soil, air, and vegetables by collecting and analyzing samples. Secondly, we will select specific populations who are workers in greenhouse area, adults who live the periphery, and general vegetable edible people to keep the activity diary in greenhouse area and food diary, and statistically get the local exposure parameters. Then, the vegetable trade matrix will be constructed among the three regions, which affect the concentration of phthalate esters in greenhouse vegetables consumed by local people. Finally, the exposure dose of different populations will be quantified, accompanied by regional variations analysis. The aim of this project is to provide data and scientific support for human exposure risk assessment of greenhouse vegetable systems, and offer a reference to other regions.

随着我国设施面积与设施蔬菜消费量的激增，设施蔬菜生产及食用过程中酞酸酯的人体暴露风险增加。这一暴露评估的关键之一，主要暴露参数的研究，基本仍处于直接采用推荐值或参考值来量化酞酸酯的暴露水平。然而，不同区域的土壤、温室类型、蔬菜种类差别大，各人群在设施菜地的行为活动不同、蔬菜摄入习惯迥异，沿用统一的暴露参数不能准确评估不同区域各类人群对这一系统的酞酸酯暴露水平。同时，区域间蔬菜流通频繁，这一因素在以往研究中也被忽略。针对以上问题，本项目拟分别在陕南、关中、陕北筛选设施蔬菜生产基地，通过特定样品采集，测试分析酞酸酯浓度；开展特定人群在设施菜地的行为活动和蔬菜食入特征的周期性调查，获得相应的暴露参数；同时，构建蔬菜区域流通矩阵，来准确评估各人群对设施蔬菜生产及食用的酞酸酯暴露水平，并综合剖析区域差异。研究结果可为设施蔬菜系统的酞酸酯暴露风险评估提供基础数据和科学依据，为其他地区所借鉴。

针对设施蔬菜系统中多介质邻苯二甲酸酯(酞酸酯，PAEs)污染特征不清和设施大棚工作人群潜在高PAEs暴露水平不明问题，开展系统研究。鉴于我国西部，尤其是西北地区的相关研究仍处于空白，该项目选择陕西地区的典型设施蔬菜基地为研究对象，通过设施大棚季节性多介质采样、人群筛选、季节性尿液收集、实验室测试与分析、跟踪随访、暴露场景模型与生物标志物监测相结合等研究方法，开展了设施蔬菜系统中多介质的PAEs污染特征及人体暴露研究。.研究结果主要表现在3方面：1）阐明了设施蔬菜大棚土壤、空气、蔬菜中PAEs的污染特征。DEHP和DnBP是各介质主要的PAE类化合物。陕北、关中、陕南的设施土壤中PAEs浓度的地区差异显著，总体表现为：陕南(843 μg/kg) > 关中 (363 μg/kg) > 陕北 (283 μg/kg)，且日光温室土壤 > 塑料大棚土壤。不同类型蔬菜中PAEs含量有差异：叶菜类蔬菜 > 茄果类 >根茎类，且冬季蔬菜中的PAEs含量高于夏季。设施大棚空气中PAEs以气态为主。农膜是设施蔬菜系统中PAEs最主要的来源。2) 揭示了设施蔬菜系统中多介质PAEs的迁移、分配规律。表现为DnBP主要由土壤向大气挥发，而DEHP主要由大气向土壤沉降的趋势。与土壤相比，空气是设施蔬菜中PAEs，尤其是DEHP累积的重要途径。指出PAEs在各介质间的迁移、分配规律受到大气温度、土壤有机质及农膜使用的综合影响。3) 综合评估了设施大棚工作人员的PAEs暴露水平。结果显示62.3%的样本暴露风险指数高于1，其中夏季高达79.4%；呼吸暴露和设施蔬菜摄入两大暴露途径的贡献量占其暴露总量的比重超过20%。.因此，为降低设施大棚工作人群PAEs的暴露风险，同时，为保证设施蔬菜安全，逐步停止使用含有DBP与DEHP的农膜势在必行。研究为设施蔬菜系统中PAEs的全过程管控提供了理论与数据支撑，并为其他地区所借鉴。