我国典型电子垃圾拆解地持久性有毒化学污染物污染现状

电子垃圾拆解所引起的环境问题已经受到广泛关注,根据联合国环境规划署统计,全球约70%的电子垃圾通过各种途径进入我国,而我国自身也产生大量的电子垃圾。我国电子垃圾拆解活动采用的工艺较为原始,位于广东的贵屿和浙江的台州是我国最大的两个电子垃圾拆解地,拆解过程中电子垃圾本身含有和不当处置所产生的大量持久性有毒化学污染物(如重金属、二 NFDA1 英类、溴代阻燃剂等)释放到环境中,对拆解地生态系统及居民健康造成严重的威胁。本文重点针对我国电子垃圾拆解所造成的持久性有毒污染物(PTS)污染现状、管理措施和法规、拆解区居民所面临的持久性有毒污染物暴露健康风险及其相关研究最新进展进行了分析和概括,并对电子垃圾拆解区域持久性有毒污染物及新型环境污染物研究和发展方向作了展望。     

“互联网+回收”情境下基于演化博弈的电子废弃物回收合作机理研究

基于“互联网+回收”情境,研究网络回收商和流动回收小贩在电子废弃物回收中的竞合关系,构建演化博弈模型,刻画演化博弈过程,分析相关因素对演化稳定策略走向的影响。研究结果表明,网络回收商和流动回收商小贩选择合作策略的概率与违约惩罚力度、合作后的超额收益正相关,与合作后的共同成本、单独选择合作策略付出的成本以及因搭便车行为增加的收益负相关。由于分别存在最优的超额收益分配率和共同成本分摊率,网络回收商和流动回收小贩选择合作策略的概率最大。     

中国电子废弃物押金返还政策决策模型及效应

应用博弈论研究了中国电子废弃物押金返还政策的决策模型及效应。研究表明,电子废弃物非正规回收环境成本较高时,社会福利最大化下的押金返还政策既能提高社会福利又能减少非正规回收数量;这时,只要押金返还额足够高,就可以使电子废弃物完全由正规回收者环保回收;合意的最小押金返还额取决于两类回收者单位电子废弃物处理利润:正规回收者处理利润越高、非正规回收者处理利润越低,合意的最小押金返还额越小;正规回收者单位电子废弃物处理利润越大、消费者对电子废弃物残值估计的最大值越小,社会福利越大。电子废弃物非正规回收环境成本较低时,不宜再使用社会福利最大化作为押金返还政策的决策目标。     

Determination of 41 polybrominated diphenyl ethers in soil using a pressurised solvent extraction and GC-NCI-MS method

A rapid and reliable analytical method based on pressurised solvent extraction (PSE) and GC-NCI-MS was developed for the determination of 41 different PBDEs in soil. All PBDEs, including mono- to hepta-BDEs (sum of 39 congeners), one nona-BDE and deca-BDE, were efficiently extracted from soil samples using the extraction technology of PSE. The extract was then cleaned up on a florisil column. Satisfactory separation of 41 PBDE congeners was obtained on a 15-m DB-5MS capillary column, saving the use of another 30-m column specific for the separation of mono- to hepta-BDEs. PBDEs were identified and quantified by GC-MS in negative chemical ionisation (NCI) mode, and further confirmed in semi electron impact (SEI) mode when the ion source was also NCI. The method detection limits ranged from 0.01 to 0.03?ng?g^?1?dw for mono- to hepta-BDEs, 1.43?ng?g^?1?dw for the nona-BDE and 0.20?ng?g^?1?dw for deca-BDE. The applicability of the method was tested in soil samples collected from an e-waste recycling site at Guiyu. Twenty-one PBDEs (mono- to deca-) were detected, and eighteen congeners were quantified. The concentration range of PBDEs was 0.78–436?ng?g^?1?dw. BDE-47, BDE-99, BDE-153, BDE-183, BDE-206 and BDE-209 were the dominant congeners, and BDE-209 accounted for 62% of the total PBDEs. The congener profiles of PBDEs in soil samples were similar to those in three commercial PBDE products (Penta-, Octa- and Deca-BDE), and Deca-BDE product was the most important contributor.     

Determination of polybrominated diphenyl ethers in freshwater fishes from a river polluted by e-wastes

Analytical method using mass spectrometric techniques was applied for the determination of polybrominated diphenyl ethers (PBDEs) in freshwater fishes. Fish samples collected from Nanyang River contaminated by the recycling electron-wastes (e-wastes) materials were prepared by using Soxhlet extraction and multiple-step column chromatographic clean-up. PBDEs were determined by gas chromatography (GC) coupled with ion trap mass spectrometry (for mono- to hepta-BDEs) and quadrupole mass spectrometry (for BDE-209). The method performance was evaluated with the recovery of ¹³C-labeled internal standards and with the analysis of certified reference biota. The obtained recoveries ranged from 75 to 125% with a relative standard deviation of lower than 10% for 16 PBDE congeners. The total PBDE (ΣPBDE) concentrations in fishes showed the following trend: grass carp < mud carp < crucian carp < silver carp < carp. ΣPBDE concentrations in the abdomen, back and tail muscles of carp ranged from 766, 458 and 530 ng/g w.w., and 53, 52, 45 ng/g w.w. in grass carp, respectively. The ΣPBDE concentrations in abdomen muscles were no significantly higher than in back and tail muscles in carp, crucian carp, grass carp and mud carp. PBDE congener concentrations in muscles correlated well with their lipid content. BDE-47 and BDE-28 were the most abundant congeners followed by BDE-17, BDE-15, BDE-66, BDE-154 and BDE-153 in fishes collected from Guiyu.     

Polybrominated Diphenyl Ethers and Heavy Metals in a Regulated E-Waste Recycling Site,Eastern China: Implications for Risk Management

Serious pollution of multiple chemicals in irregulated e-waste recycling sites (IR-sites) were extensively investigated. However, little is known about the pollution in regulated sites. This study investigated the occurrence of 21 polybrominated diphenyl ethers (PBDEs) and 10 metals in a regulated site, in Eastern China. The concentrations of PBDEs and Cd, Cu, Pb, Sb, and Zn in soils and sediments were 1–4 and 1–3 orders of magnitude lower than those reported in the IR-sites, respectively. However, these were generally comparable to those in the urban and industrial areas. In general, a moderate pollution of PBDEs and metals was present in the vegetables in this area. A health risk assessment model was used to calculate human exposure to metals in soils. The summed non-carcinogenic risks of metals and PBDEs in the investigated soils were 1.59–3.27 and 0.25–0.51 for children and adults, respectively. Arsenic contributed to 47% of the total risks and As risks in 71.4% of the total soil samples exceeded the acceptable level. These results suggested that the pollution from e-waste recycling could be substantially decreased by the regulated activities, relative to poorly controlled operations, but arsenic pollution from the regulated cycling should be further controlled.     

电子废物拆解区禽肉中二噁英及其类似物污染分析

为了了解某市电子废物拆解区二噁英及其类似物污染情况,于2017年9月至2017年10月期间,从电子废物拆解区内的村落居民家中,随机采集了鸡、鸭、鹅、鸽及鹌鹑各2批次成年放养家禽样本,研究其肉质中17种二噁英(PCDD/FS)及12种二噁英类多氯联苯(DL-PCBs)的污染水平。利用高分辨气相色谱/高分辨双聚焦磁式质谱联用(HRGC/HRMS)对采集的10批次家禽样本进行分析。结果发现,参照欧盟现行《2014/663/EU》行动标准及《(EU) No 1259/2011》最大限量标准,6批次样本超过了二噁英毒性当量行动标准(1. 25pg/g fat),其中3批次样本(2. 40pg/g fat、2. 56pg/g fat、1. 94pg/g fat)超过最大限量标准(1. 75pg/g fat); 2批次样本(0. 930pg/g fat、2. 14pg/g fat)超过了DL-PCBs当量行动标准限量(0. 75pg/g fat); 1批次样本(3. 33pg/g fat)超过二噁英和DL-PCBs毒性当量总量最大限量标准(3. 0pg/g fat)。证实该地区存在一定程度的二噁英和DL-PCBs污染。