六株真菌对土壤中芘和苯并芘的降解及其动力学

研究了6株真菌对土壤中芘和苯并芘(BaP)的降解动态,用Michaelis-Menton和Monod动力学模型对结果进行拟合.结果表明,6株真菌对芘和BaP的降解速率有显著性差异,降解率相差不大.产黄青霉(Penicillium chrysogenum,SF04),在42d内对BaP的降解能力最强,可达71.31%,对芘的降解能力相对最弱.镰刀菌(Fusariumsp.,SF11),黑曲霉(Aspergillusniger,SF05),木霉(Trichodermasp.,SF02)和毛霉(Mucorsp.,SF06)42d对芘的降解率分别为86.22%,86.18%,85.41%,85.04%,对BaP的降解率分别为71.11%,69.44%,69.05%,69.72%.木霉(Trichodermasp.,SF02)和毛霉(Mucorsp.,SF06)对芘和BaP的降解速率均很快.     

Submicron particle-bound polycyclic aromatic hydrocarbons in the Polish teaching rooms: Concentrations, origin and health hazard

The goal of the work was to investigate the concentrations of the 16 US EPA priority polycyclic aromatic hydrocarbons(PAH) bound to submicrometer particles(particulate matter, PM_1) suspended in the air of university teaching rooms and in the atmospheric air outside. Two teaching rooms were selected in two Polish cities, Gliwice, southern Poland,and Warsaw, central Poland, differing with regard to the ambient concentrations and major sources of PM and PAH. The variabilities of indoor and outdoor 24-hr concentrations of PM_1-bound PAH, the ratio(I/O) of the indoor to outdoor 24-hr concentrations of PM_1-bound PAH, probable sources of PAH and the level of the hazard from the mixture of the 16 PAH(ΣPAH) to humans at both sites were analyzed. In both Warsaw and Gliwice, the mean concentrations of PM_1-bound ΣPAH were slightly higher in the atmospheric air than in the rooms. The indoor and outdoor concentrations of individual PAH in Gliwice were correlated,in Warsaw – they were not. Most probably, the lack of the correlations in Warsaw was due to the existence of an unidentified indoor source of gaseous PAH enriching PM_1 in phenanthrene, fluorene, and pyrene. Although the ambient concentrations of PM_1-bound PAH were low compared to the ones observed earlier at both sites, they were much higher than in other urbanized European areas. However, because of low mass share of heavy PAH in ΣPAH, the various indicators of the health hazard from the 16 PAH mixture were low compared to other regions.     

高分子量多环芳烃--苯并[a]芘的生物降解研究进展

多环芳烃(PAHs)是一类广泛分布于海洋环境中的含有两个以上苯环的有机化学污染物.苯并[a]芘(BaP)是一种由5个苯环组成的分布广泛、致癌性极强的多环芳烃化合物,人们将其作为多环芳烃的指示物,通过研究其在环境中的产生、迁移、转化、降解及毒理作用来判断多环芳烃的污染情况.BaP已成为国内外环境监测的重要指标之一.本文综述了不同环境中BaP的来源与分布,BaP在环境中的行为,微生物对BaP的代谢途径,以及微生物降解BaP的相关限制因子,并结合作者在这方面研究的部分工作与目前国际研究的热点,提出值得进一步探究的有关问题.图4表3参51     

兰州地区苯并(a)芘的环境多介质迁移和归趋模拟

利用Level Ⅲ逸度模型模拟计算了稳态假设下苯并(a)芘在兰州地区大气、水体、土壤和沉积物中的相间迁移通量、浓度分布.结果表明:大气的平流输入和化石燃料燃烧是该区域苯并(a)芘的主要来源,土壤是其最大的储库,占总残留量的99.6%;在大气、水体、土壤和沉积物中的浓度分别为1.61×10-10 mol·m-3、9.39×10-7 mol·m-3、7.13×10-4 mol·m-3和9.17×10-5mol·m-3,模型计算浓度与同期实测浓度吻合较好,验证了模型的可靠性,并通过灵敏度分析,确定了模型的关键参数.     

苯并[a]芘对马氏珠母贝鳃组织抗氧化酶活性的影响

将马氏珠母贝（Pinctada martensi）暴露于不同质量浓度（1、4和8μg.L-1）苯并[a]芘B[a]P中,检测暴露后第3、7和10天后,马氏珠母贝鳃组织抗氧化酶（超氧化物歧化酶SOD、谷胱甘肽硫转移酶GST和过氧化氢酶CAT）对苯并[a]芘胁迫的生态毒理效应。结果表明：暴露时间为3、7 d时,SOD活性无明显变化,随着暴露时间的延长,SOD活性在第10天时被激活;在胁迫初期,GST活性被激活,随后表现出逐渐降低的趋势,在暴露后10 d,不同质量浓度组GST活性变化趋于稳定。当暴露质量浓度相同时,表现出明显的时—效关系;而CAT活性在第7天被激活,随着时间的延长,高质量浓度（4和8μg.L-1）组表现出先升高后下降的趋势,并表现出一定的时-效关系。SOD、GST和CAT均可作为B[a]P污染的生物标志物,活性变化相对于SOD,GST和CAT对B[a]P的胁迫更加敏感。     

Identification of 1-hydroxypyrene in urine of dogs after pyrene injection and its excretion

With high performance liquid chromatograph and fluorospectrometry, 1-hydroxypyrene is identified as a metabolite of pyrene in the urine of dogs after intramuscular injection of pyrene. When three successive doses of 1,2 and 5 μmol/kg wt. pyrene administered, urinary excretion of 1-hydroxypyrene reaches the peak level between 24th and 48th hours. Excreted 1-hydroxypyrene consists of only about 0.05% of injected pyrene.     

Adsorption and partition of benzo(a)pyrene on sediments with different particle sizes from the Yellow River

Experiments have been carried out to study the sorption of Benzo(a)pyrene(Bap) on sediment particles from the Yellow River using a batch equilibration technique. Effects of particle size on the adsorption and partition of Bap were investigated with the particle content of 3 g/L. Several significant results were obtained from the study. (1) Isotherms of Bap could be fitted with the dual adsorption-partition model under different particle sizes, and the measured value of the adsorption and partition was in agreement with the theoretical value of the dual adsorption-partition model. (2) When the particle diameter was d ⩾ 0.025 mm, the adsorption was predominant in the sorption of Bap, which accounted for 68.7%–82.4% of the sorption. For the particles with the size of 0.007 mm⩽d<0.025 mm, the adsorption was predominant when the equilibrium concentration of Bap was 0–8.87 μg/L in the water phase; and the partition was predominant when the equilibrium concentration of Bap was higher than 8.87 μg/L in the water phase. When the particle diameter was d<0.007 mm, the partition was predominant. (3) On the point of particle size, the contribution of adsorption to sorption followed the order: “d⩾0.025 mm”>“0.007 mm ⩽d<0.025 mm” >“d<0.007 mm”. (4) The partition coefficients of Bap in solids with different particle sizes were linearly correlated with the organic content, and the K _oc of Bap was about 1.26 × 10⁵ (L/kg). Translated from Acta Scientiae Circumstantiae, 2006, 26(2): 269–274 [译自: 环境科学学报]     

Relationships between indoor and outdoor air pollution by carcinogenic PAHs and PCBs

PAHs and PCBs were collected simultaneously indoors and outdoors at eight non-smoking homes located in four buildings in high-traffic areas of Rome. The purpose was to evaluate the relevance of indoor air in contributing to the overall exposure of the urban population. The vertical distribution was also investigated by collecting outdoor samples at both road and roof level, and indoor samples in both a high and a low floor flat of each building. At one coal-heated building, samples were collected during both the heating and the non-heating season. No evident PAH source was present indoors. Indoor and outdoor daily concentrations of benzo[a]pyrene (BaP) ranged, respectively, 0.1–4.6 ng m⁻³ and 0.7–2.3 ng m⁻³. With the heating on, indoor PAH concentrations equalled or exceeded those outdoors, with BaP indoor/outdoor ratios up to 4; during the warm season, ratios decreased to 0.2–0.6. Indoor PAHs at the low floors exceeded the high-floor ones when the heating was off (vehicle exhausts being the dominant source), while being equal or lower with the heating on; the vertical gradient of indoor PAHs between different floors was within a factor of 2. Outdoor PAHs at roof level were 20–70% of those at road level, which in turn exceeded those at the medium-traffic station up to a factor of 4. The outdoor concentrations of Σ6 indicator PCBs ranged 0.1–1.6 ng m⁻³. Indoor PCB concentrations exceeded those outdoors by an approximate factor of 2–50. No vertical gradient was observed. The results indicated that indoor air may contribute to the overall exposure to PAHs and PCBs more than the urban air. They were also consistent with recent findings suggesting that indoor air can be a relevant source of PCBs for outdoor air.     

苯并[a]芘对赤子爱胜蚓线粒体编码基因表达影响研究

根据ISO 11268-1:1993方法,完成了土壤中苯并[a]芘对赤子爱胜蚓(Eisenia fetida)的人工污染模拟实验.并采用Clontech PCR-SelectTM cDNA Subtration Kit构建了污染组和对照组蚯蚓之间的抑制消减文库.经测序和比对分析,在苯并[a]芘诱导上调文库中发现5个线粒体DNA(mtDNA)编码的基因,且在上调文库中具有较高的频率.它们分别为:细胞色素c氧化酶亚基Ⅰ、Ⅱ、Ⅲ,NADH氢脱氢酶亚基1,ATP合成酶亚基.研究表明,土壤中苯并[a]芘污染改变了蚯蚓线粒体基因组的表达水平,线粒体基因组表达异常是多环芳烃污染胁迫的重要分子生物标记物.