环境科学  2020, Vol. 41 Issue (10): 4740-4748   PDF    
浙江省台州市电子垃圾拆解地多溴联苯醚浓度水平分布特征和迁移趋势
魏抱楷1, 柳晨1, 王英1, 金军1,2     
1. 中央民族大学生命与环境科学学院, 北京 100081;
2. 北京市食品环境与健康工程技术研究中心, 北京 100081
摘要: 本研究分析了浙江省台州市电子垃圾拆解地及其周边表层土壤和大气中多溴联苯醚(PBDEs)的浓度水平.结果表明,台州市峰江和滨海的拆解园区、农田和居住区土壤中∑12PBDEs含量(以dw计)范围分别为21.8~1310 ng ·g-1和6.19~220 ng ·g-1,PBDEs单体分布没有显著差异.峰江和滨海两地大气中∑12PBDEs质量浓度范围分别为262~3240 pg ·m-3和840~2990 pg ·m-3,浓度中值分别为1410 pg ·m-3和840 pg ·m-3(冬季)、1590 pg ·m-3和1960 pg ·m-3(夏季),除去BDE209外的11种PBDEs单体分布在冬夏两季呈现显著性差异.通过土-气交换逸度分析发现峰江和滨海PBDEs在土-气分布迁移趋势上呈现一定的差异性.峰江PBDEs的迁移趋势主要以土壤挥发为主,土壤是大气中3~5溴代BDEs的排放源,温度的升高可以促进这一过程,这说明峰江土壤中PBDEs已成为污染释放源,建议应对峰江电子垃圾拆解园区土壤和附近农田开展土壤修复.滨海PBDEs的迁移趋势则主要以大气沉降为主,土壤是PBDEs主要的汇,说明滨海的拆解园成为PBDEs的新排放源.
关键词: 多溴联苯醚(PBDEs)      电子垃圾拆解地      土壤      大气      土-气交换     
Polybrominated Diphenyl Ether in E-waste Dismantling Sites in Taizhou City, Zhejiang Province: Concentration, Distribution, and Migration Trend
WEI Bao-kai1 , LIU Chen1 , WANG Ying1 , JIN Jun1,2     
1. College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China;
2. Engineering Research Center for Food Environment and Health, Beijing 100081, China
Abstract: The concentration of polybrominated biphenyl ethers (PBDEs) in surface soil and atmosphere of e-waste dismantling sites in Taizhou city, Zhejiang Province was determined. The concentration ranges of ∑12PBDEs in surface soil of e-waste dismantling site, farmland, and resident areas in Fengjiang Town (FJ) and Binhai Town (BH) were 21.8-1310 ng ·g-1 and 6.19-220 ng ·g-1, respectively. No significant difference was observed in the distribution of PBDEs between the FJ and BH soil. The concentration range of ∑12PBDEs in the atmosphere of FJ and BH were 262-3240 pg ·m-3 and 840-2990 pg ·m-3, respectively. The median levels of PBDEs in the atmosphere of FJ and BH were 1410 pg ·m-3 and 840 pg ·m-3 in winter and 1590 pg ·m-3 and 1960 pg ·m-3 in summer, respectively. However, a significant difference was observed in the distribution of 11 PBDE congeners, except BDE-209, during winter and summer seasons. The migration trend analysis showed the differences between the soil and air of FJ and BH. The main migration trend of 3-5-BDEs was the volatilization from soil to atmosphere, and the increase in temperature promoted the volatilization of these PBDEs from soil to atmosphere in FJ. This indicated that the PBDEs in soil had become a major source of pollution emission and suggested that soil remediation should be carried out at the e-waste dismantling site and parts of farmland in FJ. Contrary to FJ, atmospheric deposition was the major migration trend of PBDEs and the soil was the main sink of PBDEs in BH. This indicated that e-waste dismantling site in BH could be a new source of PBDEs emission in this area.
Key words: polybrominated biphenyl ethers (PBDEs)      e-waste dismantling sites      soil      atmosphere      soil-air exchange     

多溴联苯醚(polybrominated biphenyl ethers, PBDEs)是一类广泛分布于环境介质中的持久性有机污染物[1], 目前已知的同系物共209种, 因其持久性、毒性、致癌性和致突变性可对人类健康产生严重的影响[2].PBDEs等半挥发性有机污染物易通过挥发[3] -沉降[4]作用在环境中广泛分布.同时, 受其理化性质、微生物降解、气候(温度, 蒸气压等)和化学排放等因素的影响, 环境中的PBDEs会在土壤和空气两种介质中不断迁移[5~8].

浙江省台州市属亚热带季风性气候, 是我国重要的电子垃圾拆解地, 主要包括峰江再生金属加工园区和滨海金属资源再生产业基地.其中峰江于2002年底建成并投入使用, 经调查现已废弃[9]; 滨海金属资源再生产业基地则是近年来台州新规划的资源再生产业基地, 目前正在投入使用, 主要处理工艺包括分类、露天燃烧、填埋和酸洗等[10, 11].有研究表明[3], 电子垃圾拆解园区由于家庭作坊式的落后工艺可在处理过程中释放大量有机污染物, 拆解地周边地区受PBDEs等有机污染物污染严重[12~14].目前为止, 有关台州地区电子垃圾拆解地的报道国内多集中在污染严重的峰江地区, 对于近年来新增的滨海拆解园和附近农田及居住区中PBDEs浓度水平和分布趋势研究相对较少, 并且在峰江废弃后, 关于其环境中PBDEs迁移趋势的报道很有限; 而PBDEs在环境中的迁移趋势很可能受外部条件和自身理化性质的影响而出现差异[15].因此研究峰江和滨海地区PBDEs浓度水平分布特征以及探讨两地PBDEs土壤-大气间迁移趋势的差异, 对于治理电子垃圾拆解地环境中PBDEs污染的季节变化和空间差异就具有重要意义.基于此, 本研究以台州市新旧两个典型电子垃圾拆解园区及其周边农田和居住区为对象, 分析PBDEs在表层土壤和大气中的水平分布特征和其在大气-土壤中迁移趋势, 以期为进一步提出环境治理措施提供依据.

1 材料与方法 1.1 材料与标准物质

标准物质12C12-BDE(-15、-28、-47、-66、-85、-99、-100、-139、-153、-154、-183、-190)和同位素内标13C12-BDE-139、13C12-BDE-209购置于美国Cambridge Isotope Laboratories.活性硅胶, 将中性硅胶(农残级, 德国MERCK公司)以3倍体积的二氯甲烷淋洗活化, 180℃烘烤至少1 h, 冷却后充分振荡至无结块, 保存于干燥器中; 酸性硅胶:每100.0 g活性硅胶中加入44.0 g浓硫酸, 充分振荡至无结块; 碱性硅胶:每100.0 g活性硅胶中加入30.0 g NaOH溶液(1 mol·L-1), 充分振荡至无结块.无水硫酸钠(分析纯)450℃灼烧5 h脱除结晶水; 丙酮、二氯甲烷和正己烷(农残级)购置于美国J. B. Baker公司.

1.2 样品采集及保存

于2016年10月在浙江省台州市峰江再生金属加工园区和峰江以东距离16 km的滨海金属资源再生产业基地及其周边的农田、居住区采集0~5 cm表层土壤, 采样点分布见图 1.在1 m2范围内5点取样, 等量均匀混合后为一个土壤样品, 共计采集17个土壤样品.其中, 拆解厂园区内采集5份土壤样品(S1、S2和S12~S14), 居住区域采集5份土壤样品(S3~S6和S15), 农田采集7份土壤样品(S7~S11和S16、S17).土壤样品密实袋中密封保存, -4℃冷藏转运至实验室, -20℃冷冻保存至分析.

S代表土壤样品,A代表大气样品 图 1 浙江省台州市土壤和大气采样点分布情况 Fig. 1 Soil and air sampling sites in Taizhou City, Zhejiang Province

通过PUF被动式采样器采集土壤采样点附近大气样品, 采样时间分为冬夏两个阶段, 共采集10个.冬季采集于2016年10月24日至12月29日(66 d; 大气样品A1、A2、A3和A4)盛行西北风, 夏季采集于2017年7月19日至10月24日(99 d; 大气样品A5、A6、A7、A8、A9和A10)盛行东南风.冬季采样期间的平均温度为17.1℃, 夏季采样期间的平均温度为24.8℃.

1.3 样品前处理

取适量均匀混合后的土壤样品真空冷冻干燥(-70℃), 研磨过60目筛, 称取10.0 g; 将采集到PUF样品去除表面粗颗粒.分别向上述固体样品中依次加入2.5 ng 13C12-BDE-139和25 ng 13C12-BDE-209, 在索氏提取器中用300.0 mL正己烷/丙酮混合溶液(1:1, 体积比)连续提取24 h.将提取液旋转蒸发至4 mL, 再以复合硅胶柱净化.复合硅胶柱自下而上分别装适量石英棉、1.0 g活化硅胶、4.0 g碱性硅胶、2.0 g活化硅胶、8.0 g酸性硅胶和4.0 g无水硫酸钠.以50.0 mL正己烷活化, 注入样品, 20.0 mL正己烷预淋洗, 再以100 mL正己烷/二氯甲烷混合溶液(97:3, 体积比)洗脱.收集洗脱液, 氮吹定容至100 μL.

1.4 样品分析

样品采用Agilent 6890N-5975气相色谱-质谱联用仪分析.

色谱条件:BDE-15、BDE-28、BDE-47、BDE-66、BDE-100、BDE-99、BDE-85、BDE-154、BDE-153、BDE-183和BDE-190采用DB-5MS柱(30 m×0.25 mm i.d, 膜厚0.10 μm; 美国J & W Scientific); BDE-209采用DB-5MS柱(15 m×0.25 mm i.d, 膜厚0.10 μm; 美国J & W Scientific).载气为高纯氦气, 流速为1.0 mL·min-1.采用不分流模式进样, 进样量1.0 μL.

升温程序:除BDE-209外, 初始温度100℃, 保持3 min, 之后以4℃·min-1的速度升至300℃, 保持8 min; BDE-209初始温度为100℃, 保持3 min, 之后以10℃·min-1的速度升至300℃, 保持8 min.

质谱条件:进样口、离子源和四级杆的温度分别为290、150和150℃.使用负化学电离源(NCI), 反应气甲烷, 以选择离子模式(SIM)定量分析.各目标化合物均采用同位素内标法及五点稀释法定量, 标准曲线相关系数R2>0.999 0.

1.5 质量控制

定量限选用10倍信噪比, 土壤、大气样品中PBDEs(除BDE-209)的方法检出限分别为9.92~59.3 pg·g-1(以干重dw计)、0.028 9~2.16 pg·m-3, BDE-209的方法检出限为0.992~1.19 ng·g-1 (以dw计)和2.89~43.3 pg·m-3.每次实验均设置空白组, 其均未检出目标化合物.内标物13C12-BDE-139和13C12-BDE-209回收率分别为(91.4±21.0)%和(86.2±42.9)%.

1.6 统计分析方法

数据的统计分析使用SPSS 20.0软件(美国SPSS).小于检出限(N.D.)的值, 按检出限的0.5倍计算.数据通过非正态性检验后, 使用Spearman相关性检验进行相关性分析, P < 0.05时表示相关性显著.使用非参数卡方检验进行独立样本间差异分析, P < 0.05时表示差异性显著.

2 结果与讨论 2.1 浙江省台州市电子垃圾拆解地区土壤中PBDEs的水平分布特征

浙江省台州市研究区域土壤中Σ12PBDEs (包括BDE-15、BDE-28、BDE-47、BDE-66、BDE-100、BDE-99、BDE-85、BDE-154、BDE-153、BDE-183、BDE-190和BDE-209)含量(以dw计)范围为6.19~1 310 ng·g-1.其中, 峰江土壤中Σ12PBDEs 的含量范围为21.8~1 310 ng·g-1, 中值为147 ng·g-1.滨海土壤中Σ12PBDEs 的含量范围为6.19~220 ng·g-1, 中值是47.2 ng·g-1(表 1).BDE-209是土壤中主要单体, 占比超过65%, 其中滨海土壤中BDE-209占比高于峰江, 但是两地土壤在12种PBDEs单体构成上没有显著性差异(P=0.06). La等[16]的研究结果显示, 含有十溴联苯醚的Saytex 102E和Bromkal 82-0DE是目前使用最广泛的PBDEs商业品, 其中BDE-209的占比分别为96.8%和91.6%, 而目前BDE-209也是我国唯一没有被禁用的溴代阻燃剂, 因此滨海土壤中BDE-209占比高于峰江这一现象可能与峰江拆解园已废弃而滨海拆解园正在使用有关[9].除去BDE-209外的11种PBDEs中BDE-99为两地土壤中PBDEs主要单体(25%~28%), BDE-47次之, 占比20%~25%.

表 1 台州市电子垃圾拆解地周边土壤中PBDEs的含量1) Table 1 Concentration of polybrominated diphenyl ethers in soil from the e-waste dismantling sites in Taizhou City

按照采样地所在的功能区, 除BDE-209外的11种PBDEs(Σ11PBDEs) 的含量中值由高到低顺序为:峰江拆解园>峰江居住>峰江农田>滨海拆解园>滨海居住区>滨海农田, 而BDE-209的含量中值由高到低顺序为:峰江拆解园>峰江居住区>滨海拆解园>峰江农田>滨海居住区>滨海农田, 详见图 2表 1.峰江各功能区土壤中PBDEs的含量水平均显著高于对应的滨海各功能区, 这与峰江历史上长期的电子垃圾拆解活动有关[17, 18].

图 2 浙江省台州市电子垃圾拆解地周边土壤中PBDEs的中值含量 Fig. 2 Median concentrations of polybrominated diphenyl ethers in soil samples from the e-waste dismantling sites in Taizhou City, Zhejiang Province

峰江拆解园内土壤中总PBDEs的含量(Σ12PBDEs :350~1 310 ng·g-1)低于浙江省温岭市电子垃圾回收地区[19]、广东省贵屿镇电子垃圾回收地区[20]和龙塘镇电子垃圾拆解地区[21]及越南兴安省某非法电子垃圾回收地区[22], 与广东省贵屿镇某电子垃圾露天焚烧场地[23]的水平处于同一数量级, 高于中国南部某电子垃圾回收地区[24]含量水平.滨海拆解园土壤中PBDEs的含量(Σ12PBDEs : 56.9~220 ng·g-1)皆低于上述已报道地点, 但高于山西省太原市某工业区[25]和加纳Agbogbloshie电子废料市场[26]的水平.从时间维度来看, 本研究中峰江拆解园土壤中PBDEs的含量较2007年时[Σ10PBDEs (除BDE15和BDE190): 71.6~5 710 ng·g-1] [27]降低, 其中BDE-209水平明显降低, 而3~5溴代BDEs(BDE-28、BDE-47和BDE-85等)水平有所上升.Wang等[28]在浙江省台州市路桥区的调查结果也显示了拆解园土壤中PBDEs的平均含量从2005~2011年下降了近20%.

峰江拆解园周边农田土壤中PBDEs的含量水平(Σ 12PBDEs :21.8~460 ng·g-1)高于广东省清远市[29, 30]电子拆解(回收)地附近农田和2012年台州市拆解地旁农田土壤的研究[31], 而滨海拆解园周边的农田中PBDEs水平(Σ12PBDEs :6.19~14.3 ng·g-1)皆低于上述研究地点, 但高于越南北部Hung Yen省电子垃圾回收地附近水稻田中的含量水平(Σ 14PBDEs:N.D.~8.20 ng·g-1)[22].此外, 本研究区域居住区土壤中PBDEs的含量水平(峰江居住区121~428 ng·g-1, 滨海居住区37.5 ng·g-1)低于我国广东省贵屿电子垃圾回收地[32, 33]和河北省文安废塑料回收地[34]附近居住区的水平, 并低于美国环境保护署(EPA)对居住区土壤中PBDEs的污染状况推荐的初步修复标准的建议限值(Penta-BDEs:120 mg·kg-1和Deca-BDEs:610 mg·kg-1)[35], 但值得关注的是在峰江拆解园区的土壤超过了EPA推荐的居住区土壤的修复建议限值.因此, 鉴于峰江拆解园区周边有居民区, 建议对该区域的土壤进行修复.

2.2 浙江省台州市电子垃圾拆解地区大气中PBDEs的水平分布特征 2.2.1 大气中PBDEs浓度计算

PUF可以捕获大气中的目标污染物, 且具有能耗低和大范围地长期监测的优点[36].本研究中大气样品的采样时间未超过100 d, 大气中气相目标污染物与PUF被动采样器的交换可视为线性吸收[37].大气中目标污染物的浓度水平以式(1)和式(2)计算[36, 38].

(1)
(2)

式中, Veff是有效采样体积(m3); KA是空气传质系数(95 m·d-1)[5, 6], APUF是PUF盘的表面积(0.036 5 m2); t是采样时间(d), MPBDEs是一个PUF盘上PBDEs的质量(ng); cair是大气中气相PBDEs的浓度(ng·m-3).

2.2.2 大气中浓度水平及分布特征

浙江省台州市电子拆解地区大气中Σ 12PBDEs 的浓度水平为26.0~3 240 pg·m-3, 浓度中值为1 250 pg·m-3, 如表 2所示.其中, 峰江大气中Σ 12PBDEs 的浓度水平为26.0~3 240 pg·m-3, 浓度中值为1 400 pg·m-3; 滨海大气中Σ 12PBDEs 的浓度水平837~2 993 pg·m-3, 浓度中值为935 pg·m-3.在冬季, 峰江大气中Σ 12PBDEs 的浓度水平高于滨海; 而在夏季, 两地大气中PBDEs浓度水平均有所提升, 同时滨海浓度略高于峰江, 通过夏季大气中两地12种PBDE单体构成比较, 滨海BDE-209占比(99%)高于峰江(85%), 因此夏季浓度水平高于冬季及滨海夏季浓度高于峰江, 可能与两季的温度差异及峰江拆解园已废弃而滨海拆解园正在使用有关.

表 2 台州市电子垃圾拆解地大气中PBDEs含量1) Table 2 Concentrations of PBDEs in air from the e-waste dismantling sites in Taizhou City

台州市电子垃圾拆解地区大气中PBDEs的浓度水平远高于中国南部某电子垃圾拆解地[39]及越南某市电子拆解地[40]大气中PBDEs浓度, 但低于天津子牙电子垃圾回收经济园[41]、广东清远市电子拆解地[42]和广东贵屿电子拆解地[43]大气中PBDEs水平.与台州地区大气的历史数据相对比, 本研究报道的大气中PBDEs的浓度略低于Li等[44]在2008年检测的台州电子拆解园区附近大气中PBDEs浓度, 但高于Han等[45]和Zhang等[3]分别在2006~2007年和2010~2012年调查的台州电子垃圾拆解地区大气中PBDEs的浓度水平, 表明近年来大气中PBDEs浓度水平没有明显下降, 可能仍存在PBDEs的排放源, 当地电子垃圾拆解活动造成的污染仍不容乐观, 值得进一步关注.

峰江和滨海冬夏两季大气12种PBDEs中BDE-209是主要单体, 占比超过90%, 除去BDE-209剩余11种PBDEs单体分布在冬季差异性不显著(卡方检验P=0.09);同时, 峰江、滨海冬季大气和两地土壤中11种PBDEs单体构成没有显著性差异(峰江:P=0.06;滨海:P=0.09), BDE-99、BDE-47和BDE-183是主要单体, 滨海冬季大气没有发现BDE-28、BDE66和BDE-85, 而这些物质在滨海土壤中有较低的占比, BDE-47占比和峰江冬季大气与滨海土壤相比有所提升, 如图 3所示.而在夏季, 峰江和滨海大气中11种PBDEs构成和冬季两地大气及土壤相比具有显著性差异(峰江冬夏大气, P=0.03, 夏季大气和土壤, P=0.03;滨海冬夏大气, P=0.05, 夏季大气和土壤P=0.03), 峰江夏季BDE-15占比提升; 滨海夏季BDE-15、BDE-28、BDE-66和BDE-85占比明显提升, 这可能与PBDEs在土壤-大气中的迁移趋势有关.

图 3 浙江省台州市峰江和滨海冬夏两季大气和土壤中11种PBDEs组成分布 Fig. 3 Composition profiles of eleven PBDEs congener in soil and air during different seasons from FJ and BH in Taizhou City, Zhejiang Province

2.3 PBDEs在峰江和滨海地区土壤-大气迁移趋势 2.3.1 土壤-大气逸度模型的计算

逸度系数(fugacity fraction, f)常用于描述半挥发性污染物在土壤与空气之间的交换状态[46, 47].本研究中, 土壤逸度(fs)和大气逸度(fa)根据下式分别计算[46]

(3)
(4)

式中, Csoil是土壤中PBDEs的含量(ng·g-1), cair是大气中气相PBDEs的浓度(ng·m-3), R是气体常数[8.314 J· (mol·K)-1], T′是温度(K), φSOM是土壤中有机质的含量(本文取0.01 g·g-1)[48], Koa是辛醇水分配系数(以美国环保署Suite软件计算).

f的值定义为土壤逸度与总逸度的比值, 详见式(5):

(5)

f接近0.5时, 半挥发性污染物在土壤与空气中分布平衡; f>0.5时, 半挥发性污染物从土壤向空气挥发; f < 0.5时, 半挥发性污染物从空气向土壤沉降[12].考虑到f的不确定性和潜在误差, 实践中常取f大于0.7时表示半挥发性污染物从土壤向空气挥发, f值小于0.3时表示半挥发性污染物从空气向土壤沉降[4, 47].

2.3.2 峰江和滨海PBDEs土壤-大气迁移趋势的比较

排除检出率较低的PBDEs(BDE-15、BDE-154和BDE-190)后, 利用公式(3)~(5)计算土壤和大气中PBDEs各单体的逸度系数f.如图 4所示, 峰江拆解园和部分农田冬夏两季BDE-28、BDE-47、BDE-66、BDE-85和BDE-99等3~5溴代BDEs的f值多大于0.7, 环境中BDEs同系物的f值在冬、夏两季具有一定差异, 夏季明显高于冬季.这说明在峰江的BDE-28、BDE-47、BDE-66、BDE-85和BDE-99等3~5溴代BDEs的土气迁移趋势主要以土壤向大气挥发为主, 同时温度的升高会促进PBDEs从土壤向大气的挥发行为.而BDE-153、BDE-183和BDE-209等7~10溴代BDEs的f值在冬季则多小于0.3, 尽管夏季的f值略高于冬季, 但大多小于0.7;说明峰江的BDE-153、BDE-183和BDE-209等7~10溴代BDEs不易从土壤迁移至大气.以上分析表明, 峰江拆解园区在废弃后, 拆解园和部分农田的土壤已成为大气中PBDEs的释放源, 其中3~5溴代BDEs更容易迁移至大气, 这一趋势在夏季更为明显.由于台州市夏季风向以东南风为主, 挥发到大气中的PBDEs对峰江拆解园区下风向的居住区会造成较大的影响(图 1).

图 4 浙江省台州市PBDEs土-气交换土壤逸度与总逸度的比值(f) Fig. 4 Fugacity fractions of PBDEs soil-air exchange in Taizhou City, Zhejiang Province

在滨海农田和居住区, 冬季BDE-15、BDE-47、BDE-99、BDE-100等3~5溴代BDEs的f值多数介于0.3~0.7之间, BDE-153、BDE-183和BDE-209等7~10溴代BDEs的f值小于0.3, 这说明在滨海冬季PBDEs的土气交换趋势主要以大气沉降为主.夏季的f值受温度影响要略高于冬季, 其中滨海拆解园区3~5溴代BDEs的f值变化较明显, BDE-99和BDE-153的f值多大于0.7.夏季大气检出了BDE-28、BDE-66和BDE-85等冬季未检出的物质, 而这些PBDEs单体在夏季的峰江更容易从土壤中挥发, 这说明夏季随着温度的升高不仅滨海拆解园区土壤中3~5溴代BDEs单体更容易迁移至大气, 而且夏季更容易受到峰江电子垃圾拆解地土壤释放3~5溴代BDEs的影响.但总体上看, 滨海地区冬夏两季的f值并不具有显著性差异, 大部分f值仍然小于0.7, 这表明在滨海地区PBDEs的土-气交换趋势主要以大气沉降为主.因此, 滨海地区正在进行的电子垃圾拆解活动是该地区PBDEs主要的来源.

3 结论

本研究结果显示, 现已废弃的台州市峰江电子垃圾拆解园土壤中 Σ12PBDEs 含量水平近年来有所下降, 但依然高于新建的滨海拆解园土壤的水平.台州市电子垃圾拆解地大气中Σ 12PBDEs 浓度水平近年来没有明显下降, 对比冬夏两季浓度和水平分布, 峰江和滨海夏季大气中PBDEs浓度水平要高于冬季, 且PBDEs单体分布呈现显著性差异.土壤-大气交换逸度分析结果表明, 峰江和滨海两地PBDEs在土气迁移趋势上呈现出差异.峰江PBDEs的迁移趋势主要以土壤挥发为主, 3~5溴代BDEs更容易通过挥发从土壤迁移至大气中, 温度的升高可以促进这一过程.峰江土壤的污染较严重, 在拆解园区废弃后拆解园区土壤和附近农田土壤依然是台州地区大气中3~5溴代BDEs的排放源, 因此建议对峰江电子垃圾拆解园区内土壤和附近农田开展土壤修复.而滨海PBDEs迁移趋势主要以大气沉降为主, 土壤是PBDEs主要的汇, 说明位于滨海的拆解园正成为PBDEs的排放新源.

参考文献
[1] D'Silva K, Fernandes A, Rose M. Brominated organic micropollutants-igniting the flame retardant issue[J]. Critical Reviews in Environmental Science and Technology, 2004, 34(2): 141-207.
[2] Cetin B, Odabasi M. Particle-phase dry deposition and air-soil gas-exchange of Polybrominated Diphenyl Ethers (PBDEs) in Izmir, Turkey[J]. Environmental Science & Technology, 2007, 41(14): 4986-4992.
[3] Zhang T, Huang Y R, Chen S J, et al. PCDD/Fs, PBDD/Fs, and PBDEs in the air of an e-waste recycling area (Taizhou) in China:current levels, composition profiles, and potential cancer risks[J]. Journal of Environmental Monitoring, 2012, 14(12): 3156-3163.
[4] Yadav I C, Devi N L, Li J, et al. Environmental concentration and atmospheric deposition of halogenated flame retardants in soil from Nepal:source apportionment and soil-air partitioning[J]. Environmental Pollution, 2018, 233: 642-654.
[5] Park J S, Wade T L, Sweet S. Atmospheric distribution of polycyclic aromatic hydrocarbons and deposition to Galveston Bay, Texas, USA[J]. Atmospheric Environment, 2001, 35(19): 3241-3249.
[6] Yue C Y, Li L Y. Filling the gap:estimating physicochemical properties of the full array of polybrominated diphenyl ethers (PBDEs)[J]. Environmental Pollution, 2013, 180: 312-323.
[7] Meijer S N, Steinnes E, Ockenden W A, et al. Influence of environmental variables on the spatial distribution of PCBs in Norwegian and U.K. soils:implications for global cycling[J]. Environmental Science & Technology, 2002, 36(10): 2146-2153.
[8] Meijer S N, Shoeib M, Jantunen L M M, et al. Air-soil exchange of organochlorine pesticides in agricultural soils. 1. Field measurements using a novel in situ sampling device[J]. Environmental Science & Technology, 2003, 37(7): 1292-1299.
[9] 陈菡, 顾培龙. 浙江省进口废物环境管理现状及对策研究[J]. 环境污染与防治, 2008, 30(12): 96-99.
Chen H, Gu P L. Situation and countermeasure study on environmental management of import waste in Zhejiang[J]. Environmental Pollution and Control, 2008, 30(12): 96-99.
[10] Fu J J, Zhou Q F, Liu J M, et al. High levels of heavy metals in rice (Oryza sativa L.) from a typical E-waste recycling area in southeast China and its potential risk to human health[J]. Chemosphere, 2008, 71(7): 1269-1275.
[11] Zhao G F, Xu Y, Li W, et al. PCBs and OCPs in human milk and selected foods from Luqiao and Pingqiao in Zhejiang, China[J]. Science of the Total Environment, 2007, 378(3): 281-292.
[12] Zhao G F, Wang Z J, Dong M H, et al. PBBs, PBDEs, and PCBs levels in hair of residents around e-waste disassembly sites in Zhejiang Province, China, and their potential sources[J]. Science of the Total Environment, 2008, 397(1-3): 46-57.
[13] Luo X J, Liu J, Luo Y, et al. Polybrominated Diphenyl Ethers (PBDEs) in free-range domestic fowl from an e-waste recycling site in South China:levels, profile and human dietary exposure[J]. Environment International, 2009, 35(2): 253-258.
[14] Zheng J, Chen K H, Luo X J, et al. Polybrominated Diphenyl Ethers (PBDEs) in paired human hair and serum from e-waste recycling workers:source apportionment of hair PBDEs and relationship between hair and serum[J]. Environmental Science & Technology, 2014, 48(1): 791-796.
[15] Degrendele C, Audy O, Hofman J, et al. Diurnal variations of air-soil exchange of semivolatile organic compounds (PAHs, PCBs, OCPs, and PBDEs) in a central European receptor area[J]. Environmental Science & Technology, 2016, 50(8): 4278-4288.
[16] La Guardia M J, Hale R C, Harvey E. Detailed Polybrominated Diphenyl Ether (PBDE) congener composition of the widely used penta-, octa-, and deca-PBDE technical flame-retardant mixtures[J]. Environmental Science & Technology, 2006, 40(20): 6247-6254.
[17] Fu J J, Wang Y W, Zhang A Q, et al. Spatial distribution of polychlorinated biphenyls (PCBs) and Polybrominated Biphenyl Ethers (PBDEs) in an e-waste dismantling region in southeast China:use of apple snail (Ampullariidae) as a bioindicator[J]. Chemosphere, 2011, 82(5): 648-655.
[18] Chi X W, Wang M Y L, Reuter M A. E-waste collection channels and household recycling behaviors in Taizhou of China[J]. Journal of Cleaner Production, 2014, 80: 87-95.
[19] Tang X J, Zeng B, Hashmi M Z, et al. PBDEs and PCDD/Fs in surface soil taken from the Taizhou e-waste recycling area, China[J]. Chemistry and Ecology, 2014, 30(3): 245-251.
[20] Leung A O W, Luksemburg W J, Wong A S, et al. Spatial distribution of polybrominated diphenyl ethers and polychlorinated dibenzo-p-dioxins and dibenzofurans in soil and combusted residue at Guiyu, an electronic waste recycling site in southeast China[J]. Environmental Science & Technology, 2007, 41(8): 2730-2737.
[21] Wang S, Zhang S Z, Huang H L, et al. Characterization of Polybrominated Diphenyl Ethers (PBDEs) and hydroxylated and methoxylated PBDEs in soils and plants from an e-waste area, China[J]. Environmental Pollution, 2014, 184: 405-413.
[22] Matsukami H, Tue N M, Suzuki G, et al. Flame retardant emission from e-waste recycling operation in northern Vietnam:environmental occurrence of emerging organophosphorus esters used as alternatives for PBDEs[J]. Science of the Total Environment, 2015, 514: 492-499.
[23] Luo Q, Wong M H, Wang Z J, et al. Polybrominated diphenyl ethers in combusted residues and soils from an open burning site of electronic wastes[J]. Environmental Earth Sciences, 2013, 69(8): 2633-2641.
[24] Liu H X, Zhou Q F, Wang Y W, et al. E-waste recycling induced polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and dibenzo-furans pollution in the ambient environment[J]. Environment International, 2008, 34(1): 67-72.
[25] Li K, Fu S, Yang Z Z, et al. Composition, distribution and characterization of Polybrominated Diphenyl Ethers (PBDEs) in the soil in Taiyuan, China[J]. Bulletin of Environmental Contamination and Toxicology, 2008, 81(6): 588-593.
[26] Akortia E, Olukunle O I, Daso A P, et al. Soil concentrations of polybrominated diphenyl ethers and trace metals from an electronic waste dump site in the Greater Accra region, Ghana:implications for human exposure[J]. Ecotoxicology and Environmental Safety, 2017, 137: 247-255.
[27] Ma J, Addink R, Yun S, et al. Polybrominated dibenzo-p-dioxins/dibenzofurans and polybrominated diphenyl ethers in soil, vegetation, workshop-floor dust, and electronic shredder residue from an electronic waste recycling facility and in soils from a chemical industrial complex in eastern China[J]. Environmental Science & Technology, 2009, 43(19): 7350-7356.
[28] Wang P, Zhang H D, Fu J J, et al. Temporal trends of PCBs, PCDD/Fs and PBDEs in soils from an e-waste dismantling area in east China[J]. Environmental Science:Processes & Impacts, 2013, 15(10): 1897-1903.
[29] Jiao X C, Tang Q F, Chen S, et al. Spatial distribution and temporal trends of farmland soil PBDEs:processes and crop rotation effects[J]. Environmental Science and Pollution Research, 2016, 23(13): 13137-13146.
[30] Luo Y, Luo X J, Lin Z, et al. Polybrominated diphenyl ethers in road and farmland soils from an e-waste recycling region in Southern China:concentrations, source profiles, and potential dispersion and deposition[J]. Science of the Total Environment, 2009, 407(3): 1105-1113.
[31] Dong Y, Li L, Bie P J, et al. Polybrominated diphenyl ethers in farmland soils:source characterization, deposition contribution and apportionment[J]. Science of the Total Environment, 2014, 466-467: 524-532.
[32] Zhang S H, Xu X J, Wu Y S, et al. Polybrominated diphenyl ethers in residential and agricultural soils from an electronic waste polluted region in South China:distribution, compositional profile, and sources[J]. Chemosphere, 2014, 102: 55-60.
[33] Li N, Chen X W, Deng W J, et al. PBDEs and dechlorane plus in the environment of Guiyu, southeast China:a historical location for E-waste recycling (2004, 2014)[J]. Chemosphere, 2018, 199: 603-611.
[34] Tang Z W, Huang Q F, Cheng J L, et al. Polybrominated diphenyl ethers in soils, sediments, and human hair in a plastic waste recycling area:a neglected heavily polluted area[J]. Environmental Science & Technology, 2014, 48(3): 1508-1516.
[35] EPA-540-R-05-012, Contaminated sediment remediation guidance for hazardous waste sites[S].
[36] Heo J, Lee G. Field-measured uptake rates of PCDDs/Fs and dl-PCBs using PUF-disk passive air samplers in Gyeonggi-do, South Korea[J]. Science of the Total Environment, 2014, 491-492: 42-50.
[37] Pozo K, Harner T, Shoeib M, et al. Passive-sampler derived air concentrations of persistent organic pollutants on a north-south transect in Chile[J]. Environmental Science & Technology, 2004, 38(24): 6529-6537.
[38] Herkert N J, Martinez A, Hornbuckle K C. A model using local weather data to determine the effective sampling volume for PCB congeners collected on passive air samplers[J]. Environmental Science & Technology, 2016, 50(13): 6690-6697.
[39] 陈多宏, 李丽萍, 毕新慧, 等. 典型电子垃圾拆解区大气中多溴联苯醚的污染[J]. 环境科学, 2008, 29(8): 2105-2110.
Chen D H, Li L P, Bi X H, et al. PBDEs pollution in the atmosphere of a typical E-waste dismantling region[J]. Environmental Science, 2008, 29(8): 2105-2110.
[40] Tue N M, Takahashi S, Suzuki G, et al. Contamination of indoor dust and air by polychlorinated biphenyls and brominated flame retardants and relevance of non-dietary exposure in Vietnamese informal e-waste recycling sites[J]. Environment International, 2013, 51: 160-167.
[41] Hong W J, Jia H L, Ding Y S, et al. Polychlorinated Biphenyls (PCBs) and Halogenated Flame Retardants (HFRs) in multi-matrices from an electronic waste (e-waste) recycling site in Northern China[J]. Journal of Material Cycles and Waste Management, 2016, 20(1): 80-90.
[42] Luo P, Bao L J, Wu F C, et al. Health risk characterization for resident inhalation exposure to particle-bound halogenated flame retardants in a typical E-waste recycling zone[J]. Environmental Science & Technology, 2014, 48(15): 8815-8822.
[43] Chen D H, Bi X H, Liu M, et al. Phase partitioning, concentration variation and risk assessment of Polybrominated Diphenyl Ethers (PBDEs) in the atmosphere of an e-waste recycling site[J]. Chemosphere, 2011, 82(9): 1246-1252.
[44] Li Y M, Jiang G B, Wang Y W, et al. Concentrations, profiles and gas-particle partitioning of PCDD/Fs, PCBs and PBDEs in the ambient air of an E-waste dismantling area, southeast China[J]. Chinese Science Bulletin, 2008, 53(4): 521-528.
[45] Han W L, Feng J L, Gu Z P, et al. Polybrominated diphenyl ethers in the atmosphere of Taizhou, a major e-waste dismantling area in China[J]. Bulletin of Environmental Contamination and Toxicology, 2009, 83(6): 783-788.
[46] Li Y F, Harner T, Liu L Y, et al. Polychlorinated biphenyls in global air and surface soil:distributions, air-soil exchange, and fractionation effect[J]. Environmental Science & Technology, 2010, 44(8): 2784-2790.
[47] Pokhrel B, Gong P, Wang X P, et al. Distribution, sources, and air-soil exchange of OCPs, PCBs and PAHs in urban soils of Nepal[J]. Chemosphere, 2018, 200: 532-541.
[48] HJ 25.3-2014, 污染场地风险评估技术导则[S].
HJ 25.3-2014, Technical guidelines for risk assessment of contaminated sites[S].