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131.
In this paper, several studies were conducted to evaluate the genotoxicity of two pesticides, Imidacloprid and RH-5849, for earthworm (Eisenia fetida). Earthworms were exposed in different exposure systems to evaluate their acute toxicity and the genotoxicity of the two pesticides was evaluated by using the method of sperm deformity assessment, micronucleus test of root tip cells in Vicia faba, a mouse bone-marrow micronucleus test, and comet assay. LC(50) (interpolated concentration at which 50% mortality of test population occurs) for earthworms varied in different exposure systems. The results indicated that Imidacloprid was consistently more toxic than RH-5849 in all exposure systems. In this study, sperm deformity test was used to detect the potential adverse influences of pesticides on the reproduction of earthworms. The results demonstrated that significant induction of sperm deformity (p<0.01) and a dose-effect relationship displayed at Imidacloprid concentrations higher than 0.5 mg/kg dry soil. However, the sperm deformity frequency of groups exposed to RH-5849 did not show significant difference (p>0.05) from the control until the dose reached 100 mg/kg dry soil. The results of the V. faba micronucleus tests showed that micronuclei frequency of the exposed group did not show significant difference (p>0.05) from the control until the concentration of Imidacloprid and RH-5849 reached 100 mg/ml. The results of the mouse bone-marrow micronuclei test also indicate that two pesticides did not show significant effects (p>0.05) on the micronuclei frequency in mice bone-marrow cells until the dose reached 100 mg/kg for Imidacloprid and 300 mg/kg for RH-5849 (2/3 LD(50)). Although no genotoxicity was detected by using the micronucleus tests, the results of the comet assay showed that the two pesticides induce significant DNA damage (p<0.01) in earthworms and dose-effect relationships were displayed. The 'earthworm comet assay' is a rapid and sensitive way to screen chemicals or terrestrial environments for their DNA-damaging properties. 相似文献
132.
Pollution characteristics of 23 veterinary antibiotics in livestock manure and manure-amended soils in Jiangsu province,China 总被引:3,自引:0,他引:3
Xin Y. Guo Li J. Hao Pan Z. Qiu Rong Chen Jing Xu Xiang J. Kong 《Journal of environmental science and health. Part. B》2016,51(6):383-392
The aim of this study was to investigate the pollution characteristics of typical veterinary antibiotics in manure and soil of livestock farms in Jiangsu province. This investigation employed solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A total of 53 manure and 50 amended soil samples from 16 livestock farms in Jiangsu province were collected for analysis. In the manure samples, the highest detected frequencies and concentrations were those of tetracyclines (TCs, 54.1 ± 5775.6 μgkg?1), followed by fluoroquinolones (FQs, 8.4 ± 435.6 μgkg?1), sulphonamides (SAs, 3.2 ± 5.2 μgkg?1) and macrolides (MACs, 0.4 ± 110.5 μgkg?1). Statistical analysis was used to illuminate the pollution characteristics of 23 veterinary antibiotics for various animal types and different regions in Jiangsu province. The results showed that the pollution level in cow manure was relatively lower compared with pig and chicken manure due to the relative restriction of medication. Furthermore, contamination was serious in amended soil from chicken farms. The pollution level in manure among different regions was higher to the south and north compared with the centre of the region. The same outcome was found for soil. Antibiotic residues in organic fertilizer were also investigated in this study. We found that although the detected concentration was lower in organic fertilizer than in fresh manure, detection frequencies (10–90%) were high, especially for roxithromycin (90%) in MACs (30–90%). This finding suggests attention should be paid to the pollution levels in organic fertilizer. This study is the first extensive investigation of the occurrence and distribution of many kinds of typical veterinary antibiotics in manure and soil from livestock farms of Jiangsu province. This investigation systematically assesses veterinary antibiotics usage and related emissions in southeast China. 相似文献
133.
对聚亚磺酰氨基酰胺(PSAA)作为新型抗氧化反渗透膜材料的可能性,以及聚合条件和成膜条件对膜性能的影响作了初步研究。 相似文献
134.
现行城市污水生物处理系统能耗高、工艺复杂,而且污水中蕴含着能量的有机物、可作为肥料的氮和磷在处理过程中被转化、分解或以固废被处置,从而导致资源浪费.探讨了先通过生物吸附/吸收作用将污水有机物、氮、磷从水中转移到污泥中,达到污水净化的目的;再使污泥将污染物释放出来.把有机物转化为甲烷、氮、磷沉淀后回收,污泥经活化后再次用于吸附的城市污水资源化生物净化新工艺.该工艺可以最大限度地避免污染物的氧化,将极大降低能耗,同时实现资源的回收.在此论述了实现该途径的可能性与存在的问题. 相似文献
135.
本实验研究甲醛污染的淡水和海水对细菌、植物和动物的生物学效应。甲醛的毒害作用是显著的。含0.036—0.36%甲醛的纯水能引起鼠伤寒沙门氏菌组氨酸缺陷型菌株TA100的回复突变,含0.036%、0.0036%、0.00036%甲醛的水溶液行短期(6h)处理紫露草花枝基部,24h休复后发现四分体细胞中微核率显著增高。含0.0018%、0.0036%、0.018%甲醛的水处理蚕豆根,引起根尖细胞中微核率明显增高。0.00018%甲醛的海水使马粪海胆幼虫在45min内死亡。0.0072%甲醛的海水使该幼虫在2min内死亡。0.0072%甲醛的海水能使贻贝担轮幼虫在5min内死亡。0.00018%甲醛的海水使贻贝幼虫在48h内死亡。0.000108%甲醛的海水使马粪海胆幼虫在72h内死亡。实验证明蚕豆根尖细胞和海胆幼虫是良好的监测淡水与海水污染的材料,甲醛能引起DNA中碱基对置换突变。甲醛在海水中产生增效效应。 相似文献
136.
燃煤电厂烟气脱硫技术发展现状 总被引:3,自引:0,他引:3
综述近年来国内外应用及正在研究开发的脱硫工艺,包括国内应用的石灰石-石膏,海水,磷铵复肥,喷雾干燥,炉内喷钙,电子束烟气脱硫及国外的尿素,改进的石灰石-石膏,再生法脱除SO2和NOX等新方法,并对其中发生的化学反应,特点及存在的问题进行了较详细的分析。 相似文献
137.
部分氮杂环类化合物的遗传毒性及其QSAR研究 总被引:1,自引:0,他引:1
本文利用蚕豆细胞微核试验评价了10种氮杂环类化合物的遗传毒性,一化合物的最低未占据轨道能Elumo、分子的量负的原子净电荷q建立了较好的相关方程:MN=-2.96(1.14)+4.93(0.48)Elumo+13.68(2.72)q^-R^2=0.94 SE=0.71 F=53.92 P〈0.0005推测此类化合物的至于致毒机制可能是它们作为电荷给予体和氢键予体作用于生物受体而引起的突变。 相似文献
138.
农药废水是一种典型的高浓度有机工业废水 ,有机污染物浓度高 (CODCr>10 0 0 0mg L) ,可生化性差 (氯苯农药废水BOD5 CODCr=0 .0 3 ,对邻硝基氯苯农药废水BOD5 CODCr=0 .0 5 )。采用微电解和Fenton试剂氧化两种物化手段对菊酯、氯苯和对邻硝氯苯 3种废水按比例配制而成的综合农药废水进行预处理 ,结果表明 :在废水pH为 2— 2 .5时 ,经微电解处理后 ,BOD5 CODCr比值在 0 .45以上 ,可生化性提高 ;Fenton试剂对综合农药废水CODCr去除率为 60 %左右 ,色度去除率接近 10 0 % 相似文献
139.
复合型除尘器除尘脱硫一体化工艺实验研究 总被引:2,自引:0,他引:2
试验研究了专利产品“高压静电滤槽复合型卧式除尘器”的除尘脱硫一体化工艺。试验表明,在布袋前方的末级电场中实行半干法脱硫工艺具有可行性,可达到除尘脱硫一体化目的。试验同时研究了钙硫比、脱硫灰循环率、饱和温距、喷水量和SO2浓度等对脱硫率的影响。该工艺适用于以低硫煤为燃料的锅炉进行除尘脱硫。 相似文献
140.
水热处理为纤维素废弃物资源化应用开辟了一条新的途径,文中就水热处理技术的特点、水热条件下纤维素的降解过程进行了介绍,并着重综述了纤维素废弃物水热制H2方面的研究进展,同时对纤维素及其废弃物的水热处理和资源化研究前景进行了展望。 相似文献