苯并(a)芘在黄河水体不同粒径颗粒物上的表面吸附和分配作用特征

模拟实验研究了苯并(a)芘在黄河水体不同粒径颗粒物上的吸附作用,重点探讨了颗粒物粒径对苯并(a)芘的表面吸附和分配作用的影响.结果表明:(1)苯并(a)芘在黄河水体颗粒物上的吸附符合表面吸附-分配作用复合模式(2)苯并(a)芘在粒径d≥0.025 mm颗粒物上的吸附以表面吸附为主,表面吸附对吸附的贡献在68.7%至82.4%之间;当苯并(a)芘液相平衡浓度为0～8.87μg·L-1时,其在粒径0 007 mm≤d＜0.025 mm颗粒物上的吸附以表吸附作用为主,当液相平衡浓度大于8.87μg·L-1时,吸附以分配作用为主;苯并(a)芘在粒径d＜0.007 mm颗粒物上的吸附以分配作用为主;(3)苯并(a)芘在不同粒径颗粒物上的表面吸附对总吸附的贡献大小顺序为:(d≥0.025 mm)＞(0.007 mm≤d＜0 025 mm)＞(d＜0.007 mm);(4)苯并(a)芘在不同粒径颗粒物中的分配系数与有机质含量呈线性相关,其标化分配系数Koc约为1.26×105L·kg-1.     

Antioxidant responses to benzo[a]pyrene, tributyltin and their mixture in the spleen of Sebasticus marmoratus

It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase （GPx） activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase （GST） activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH （glutathione） by BaP or TBT alone. MDA （malondialdehyde） contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.     

两株假单胞菌对蒽菲芘的降解作用

从污染污泥中分离出两株假单胞菌PCN5及PCB2。研究了它们对蒽、菲、芘的降解性能及生长繁殖情况。结果表明，单基质存在下，10h，PCN5对蒽的降解转化率为91．8％，芘为75．6％，菲仅为26．25％；相反PCB2对菲的降解效果最好，蒽最差；混合基质体系中，两菌株都有良好的降解效果，对芘的降解效果较差；130h，PCN5对蒽、菲、芘混合体系中的TOC去除率为38．9％，PCB2对相应体系的去除率为73．7％；混合体系中两株的生长曲张相似，细菌浓度均呈指数增长趋势，PCN5的最大浓度约是原加入量的10000倍，PCB2是原加入量的8000倍。     

天津污灌区苯并(a)芘的分布和迁移通量模型

建立了估算苯并 (a)芘在天津污灌区气、水、土壤及沉积物相间的迁移通量和浓度分布的逸度模型框架 ,利用通量资料作为模型输入 ,利用实测浓度数据验证了模型的可靠性 .结果表明 ,模型对大气、地表水、土壤和沉积物中浓度的估算大体吻合 ,沉积物和土壤是苯并 (a)芘的主要环境归宿 ,而大气中的平衡浓度相对较低 ,水体及土壤中的苯并 (a)芘可能通过作物和鱼体富集而进入生态系统 .     

Water solubility enhancements of pyrene by single and mixed surfactant solutions

ＩｎｔｒｏｄｕｃｔｉｏｎＳｕｒｆａｃｔａｎｔｓｅｎｈａｎｃｅｔｈｅｒｅｍｅｄｉａｔｉｏｎｏｆＮＡＰＬ ｃｏｎｔａｍｉｎａｔｅｄｓｉｔｅｓｂｙｉｎｃｒｅａｓｉｎｇｔｈｅａｑｕｅｏｕｓ ｐｈａｓｅｃｏｎｃｅｎｔｒａｔｉｏｎｏｆｔｈｅＮＡＰＬｖｉａｍｉｃｅｌｌｅｆｏｒｍａｔｉｏｎ ,ｍｉｃｒｏｅｍｕｌｓｉｆｉｃａｔｉｏｎ ,ｏｒｍｏｂｉｌｉｚｉｎｇｔｈｅＮＡＰＬｐｈａｓｅ (Ｋｉｌｅ ,1989;Ｅｄｗａｒｄｓ,1991;Ｇｕｈａ ,1998ａ ;Ｋｏ ,1998;Ｚｉｍｍｅｒｍａｎ ,1999;Ｂｅｔｔａｈａｒ,1999;Ｗｉｌｌｓｏｎ ,1999;Ｐａ…     

Combined effect of tributyltin and benzo[a] pyrene on the levels of sex hormone and vitellogenin in female Sebastiscus marmoratus

Tributyltin（TBT）, an organometal used as an antifouling biocide, has been reported to induce masculinization of fish. Benzo [a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, has been reported that its microsomal metabolites can produce an estrogenic response when tested in vitro. This study was therefore designed to examine the potential in vivo influence of TBT, BaP and their mixture on sex hormone levels in serum of Sebastiscus marmoratus, which were given 2 separate intraperitoneally （ip） injections（a single injection every 7 d） of TBT（0.5, 1, 5 and 10 mg/kg）, BaP（0.5, 1, 5 and 10 mg/kg）, or both in combination（0.5, 1, 5 and 10 mg/kg）; control fish received olive oil vehicle only. Six days after the 2nd injection, serum samples were collected and analyzed for sex hormone levels and alkali labile protein phosphorus （ALPP）, which is related to the yolk precursor protein vitellogenin. The pollutants at all doses significantly reduced serum testosterone, estradiol and ALPP content after 2 injections compared with the corresponding controls. The reduction of the estradiol levels should be response for the decrease of the vitellogenin levels. The results in the present study suggested that aromatase seems not the major target acted by TBT and BaP in fish. This study demonstrated that TBT or BaP exposure both inhibit the reproductive potential in female Sebastiscus marmoratus. Combined effect of TBT and BaP on the serum testosterone, estradiol and ALPP was not antagonism from the anticipation.     

Metabolism of benzo[a]pyrene in peroxynitrite/Fe(III) porphyrin system

The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene (B[a]P) metabolism. Three model systems consisting of different iron porphyrins were compared, and the results showed that the peroxynitrite/T(p-Cl)PPFeCl system was the highest catalytic efficiency in the metabolism of B[a]P. We analyzed the B[a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B[a]P induced by peroxynitrite.     

Reduced-glutathione concentrations in Boleophthalmus pectinirostris tissues exposed to benzo(a)pyrene

ＩｎｔｒｏｄｕｃｔｉｏｎＢｅｉｎｇａｔｙｐｉｃａｌｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓ(ＰＡＨｓ) ,ｂｅｎｚｏ[ａ]ｐｙｒｅｎｅ(ＢａＰ)ｄｅｓｅｒｖｅｓｓｅｒｉｏｕｓｓｔｕｄｙｂｅｃａｕｓｅＰＡＨｓａｒｅｎｏｗｒｅｃｏｇｎｉｚｅｄａｓｍａｊｏｒｅｎｖｉｒｏｎｍｅｎｔａｌｐｏｌｌｕｔａｎｔｓ .ＥｘｐｏｓｕｒｅｔｏＰａＨｓｉｓｖｉｒｔｕａｌｌｙｕｎａｖｏｉｄａｂｌｅａｎｄｉｓｓｔｒｏｎｇｌｙｓｕｓｐｅｎｄｅｄｏｆｂｅｉｎｇａｃａｕｓａｔｉｖｅｆａｃｔｏｒｉｎｃｅｒｔａｉｎｔｕｍｏ…     

Phytotoxicity assessment of phenanthrene, pyrene and their mixtures by a soil-based seedling emergence test

Seedling emergence tests were conducted in a meadow brown soil using five plant species ( i. e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mixtures. The soil was amended with up to 1000mg/kg soil of phenanthrene or 600 mg/kg soil of pyrene. Seedling emergence and root growth were measured. The results indicated that root elongation was more sensitive than seedling emergence. Root length decreased with increasing phenanthrene or pyrene concentrations(p≤0.05). Phenanthrene was more phytotoxic than pyrene. The lowest observable adverse effect concentration(LOAEC) was 10mg/kg for phenanthrene when tested with green onion, and 50mg/kg for pyrene when tested with wheat. Among the five species, wheat was found to be the most sensitive. When amended jointly at or below their respective LOAEC, phenanthrene and pyrene produced a synergistic toxic effect.     

Uptake and accumulation of phenanthrene and pyrene in spiked soils by Ryegrass(Lolium perenne L.)

Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.