在2009—2010年南半球夏季,用大流量采样器(high-volume air sampler,HVAS)和聚胺酯泡沫(polyurethane foam,PUF)被动采样器采集了南极菲尔德斯半岛和阿德利岛6个点的大气样品,分析了HBCDs的浓度水平、异构体组成、气相-颗粒相分配和空...在2009—2010年南半球夏季,用大流量采样器(high-volume air sampler,HVAS)和聚胺酯泡沫(polyurethane foam,PUF)被动采样器采集了南极菲尔德斯半岛和阿德利岛6个点的大气样品,分析了HBCDs的浓度水平、异构体组成、气相-颗粒相分配和空间分布趋势.主动和被动采集大气样品中ΣHBCDs浓度(α-HBCD、β-HBCD、γ-HBCD的浓度)范围分别为n.d.(未检出)—2.73 pg·m^(−3)和0.41—3.39 pg·m^(−3),与北极和偏远地区浓度水平一致,远低于城市和工业区的污染水平.HBCDs在主动采集的颗粒相和气相中的平均比例分别为67%和33%,颗粒相以α-HBCD(57%)为主,气相以γ-HBCD(53%)为主;被动采集的PUF样品中γ-HBCD(64%)占优势.经过主动采样和被动采样的对比研究,对采样速率进行校正后,PUF被动采样器可以用于南极大气样品的采集.南极大气中HBCDs的检出,表明HBCDs具有持久性和潜在的长距离大气传输能力;南极长城站附近大气中HBCDs浓度水平略高,反映了有限的人类活动对南极环境产生了影响.展开更多
为了解六溴环十二烷(HBCDs)在海洋沉积物中的好氧微生物降解特性,在以HBCDs为唯一碳源的无机培养基中添加海洋沉积物悬浮液,利用HPLC-MS/MS测定HBCDs降解率,并驯化分离得到HBCDs降解菌株,进行菌种鉴定.结果显示:海洋沉积物好氧微生物对H...为了解六溴环十二烷(HBCDs)在海洋沉积物中的好氧微生物降解特性,在以HBCDs为唯一碳源的无机培养基中添加海洋沉积物悬浮液,利用HPLC-MS/MS测定HBCDs降解率,并驯化分离得到HBCDs降解菌株,进行菌种鉴定.结果显示:海洋沉积物好氧微生物对HBCDs的降解半衰期为38-61 d;在120 d中HBCDs共降解了72%;从海洋沉积物中富集、分离得到5株能够以HBCDs为唯一碳源的降解菌株,分别命名为CTF711-A、CTF711-C、CTF711-D、CTF711-E和CTF711-X,结合形态学观察、生理生化试验和16S r DNA序列分析,将其依次鉴别为假单胞菌属、红球菌属、不动杆菌属、微杆菌属和盐单胞菌属,除假单胞菌属外,其余菌株对HBCDs的降解能力还尚未见报道.同时将这5株菌分别培养与混合培养,混合菌株对HBCDs降解率最高.本研究报道了5株不同属的HBCDs好氧降解菌株,且混合菌株对HBCDs降解效果较好,结果可为HBCDs的生物修复提供理论和应用依据.展开更多
The present study was conducted to examine the concentrations,profiles,and mass distributions of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecanes(HBCDs),and polybrominated dibenzo-p-dioxins/furans(PBDD/Fs...The present study was conducted to examine the concentrations,profiles,and mass distributions of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecanes(HBCDs),and polybrominated dibenzo-p-dioxins/furans(PBDD/Fs)based on the particle sizes of house dust samples from five homes in Japan.After removal of impurities from house dust from vacuum cleaner bags,selected indoor dust samples were size fractionated(>2 mm,1-2 mm,0.5-1 mm,250-500 mm,106-250 mm,53-106 mm,and<53 mm).Fluffy dust was collected separately for particle size analysis.PBDEs,HBCDs,and PBDFs were detected in all the samples analyzed.In general,PBDE levels of particulate and fluffy dust were comparable and the highest concentrations were found in 106-250 mm or 53-106 mm fractions.HBCD concentrations in fluffy dust were higher than those in particulate dust,and their levels were the highest in 106-250 mm and 250e500 mm factions,respectively.The highest concentrations of all three compound groups were not found in particles<53 mm in size,suggesting that the distribution of brominated flame retardants does not depend solely on the surface area-to-volume ratios of dust particles.The concentrations of PBDEs and PBDD/Fs depended principally on the concentrations in particles<53 mm in size because the predominant mass of particulate dust were found in this fraction.The mesh size used for sample preparation will thus have little effect on the concentrations as long as particles<53 mm are included.In contrast,HBCD concentrations increased by as much as 80%when particles>250 mm in size and fluffy dust were included.The conclusion is that particulate dust<250 mm in size without fluffy dust should be used to analyze dust for brominated flame retardants.展开更多
文摘为了解六溴环十二烷(HBCDs)在海洋沉积物中的好氧微生物降解特性,在以HBCDs为唯一碳源的无机培养基中添加海洋沉积物悬浮液,利用HPLC-MS/MS测定HBCDs降解率,并驯化分离得到HBCDs降解菌株,进行菌种鉴定.结果显示:海洋沉积物好氧微生物对HBCDs的降解半衰期为38-61 d;在120 d中HBCDs共降解了72%;从海洋沉积物中富集、分离得到5株能够以HBCDs为唯一碳源的降解菌株,分别命名为CTF711-A、CTF711-C、CTF711-D、CTF711-E和CTF711-X,结合形态学观察、生理生化试验和16S r DNA序列分析,将其依次鉴别为假单胞菌属、红球菌属、不动杆菌属、微杆菌属和盐单胞菌属,除假单胞菌属外,其余菌株对HBCDs的降解能力还尚未见报道.同时将这5株菌分别培养与混合培养,混合菌株对HBCDs降解率最高.本研究报道了5株不同属的HBCDs好氧降解菌株,且混合菌株对HBCDs降解效果较好,结果可为HBCDs的生物修复提供理论和应用依据.
基金supported by“Environment Research and Technology Development Fund”(K22057)from the Ministry of the Environment,Japan.
文摘The present study was conducted to examine the concentrations,profiles,and mass distributions of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecanes(HBCDs),and polybrominated dibenzo-p-dioxins/furans(PBDD/Fs)based on the particle sizes of house dust samples from five homes in Japan.After removal of impurities from house dust from vacuum cleaner bags,selected indoor dust samples were size fractionated(>2 mm,1-2 mm,0.5-1 mm,250-500 mm,106-250 mm,53-106 mm,and<53 mm).Fluffy dust was collected separately for particle size analysis.PBDEs,HBCDs,and PBDFs were detected in all the samples analyzed.In general,PBDE levels of particulate and fluffy dust were comparable and the highest concentrations were found in 106-250 mm or 53-106 mm fractions.HBCD concentrations in fluffy dust were higher than those in particulate dust,and their levels were the highest in 106-250 mm and 250e500 mm factions,respectively.The highest concentrations of all three compound groups were not found in particles<53 mm in size,suggesting that the distribution of brominated flame retardants does not depend solely on the surface area-to-volume ratios of dust particles.The concentrations of PBDEs and PBDD/Fs depended principally on the concentrations in particles<53 mm in size because the predominant mass of particulate dust were found in this fraction.The mesh size used for sample preparation will thus have little effect on the concentrations as long as particles<53 mm are included.In contrast,HBCD concentrations increased by as much as 80%when particles>250 mm in size and fluffy dust were included.The conclusion is that particulate dust<250 mm in size without fluffy dust should be used to analyze dust for brominated flame retardants.
