应用聚丙烯酰胺的环境与生态行为研究

聚丙烯酰胺(PAM)在油田中的大量使用,其环境和生态行为及降解产物对环境的潜在危害,都亟待去研究。本文分析论述了其物理、化学性质及化学降解、机械降解、热降解、生物降解性,及影响其在土壤中的被吸附的因素和生态毒理学研究,提出有待进一步研究的课题为:PAM在油藏条件下的降解机理和降解速度;PAM及其衍生物在环境中的存在形式及其迁移转化的方式,在生物体内的存在形式及其在生物圈内的迁移转化等。     

渤海湾滨海湿地土壤微生物实验室简介

正渤海湾滨海湿地土壤微生物实验室以渤海湿地"水体-土壤-生物"生态环境系统为主体研究对象,围绕该环境中污染物在环境介质中的迁移、蓄积、代谢和转化过程,借助现代分析表征手段和方法,研究污染物的环境化学行为和生态毒理效应,以及土壤微生物在转化过程中的响应及作用。实验室依托国家自然科学基金(项目编号:41201244)及河北环境工程学院实验中心,以研究污染物在海洋-河流-土壤-生物等介质间的传输和转化途径及由此导致的生态环境危害机制为主要研究内容,研究方向和相关内容如下:(一)滨海湿地系统中土壤微生物的环境生物化学     

土壤中铬的迁移转化研究进展

随着工业的发展,土壤铬污染问题日益突出,对人体和环境产生巨大危害。了解铬在土壤环境中的迁移转化行为对于预测其变化趋势和控制环境污染具有重要意义。对土壤中铬的来源、价态、危害及其在土壤中的迁移转化作用进行了综述,并重点指出影响铬迁移转化的土壤p H值、有机质、氧化还原电位、土壤类型和微生物作用等因素的研究现状,以及就进一步研究土壤中铬迁移转化的方向进行了展望。     

环境中铬污染的生态效应及其防治

从生态效应的角度介绍了重金属铬在环境中的迁移、转化规律，重点论及了铬污染对人体健康厦水生生物等其他生物的影响、对水体自净作用的影响，指出Cr^6＋的生态效应远比Cr^3＋大的多。目前治理含铬工业废水和受铬污染土壤几种有效方法，旨在引起人们对环境中铬污染的生态效应产生足够的重视和防范。     

全氟化合物的分布、累积及生态毒理学效应

全氟化合物(Perfluorinated compounds,PFCs)污染在全球范围内已普遍存在,其在环境中的浓度增长迅速,受到人们越来越多的关注。环境中PFCs的迁移转化规律决定其环境效应,是进行环境和健康风险评价的基础。目前关于PFCs的研究主要集中于水体及生物体内PFCs的分析检测,对其生态毒理效应的研究尚处于初步阶段。本文介绍了PFCs研究现状,综述了PFCs在环境中的分布模式、生物体内的蓄积规律以及环境中PFCs的生态毒理效应等方面的最新研究进展,同时也阐述了PFCs污染对人体健康的影响,并提出了未来PFCs研究亟待解决的问题。     

昌吉州土壤、粮食中重金属污染及评价

重金属在环境中不能分解,当进入土壤后能长期蓄积在土壤中,并通过土壤在环境中迁移转化:经食物和水对人体产生危害。轰动世界的公害“水俣病”和“痛痛病”就是由汞和镉引起的。由于重金属呈慢性积累性中毒,常被人们所忽视。为摸清重金属汞、砷、铬、镉、铅在昌吉州土壤及粮食中的含量,1985年我们采集了土壤、粮食样品,对其所含重金属进行了化验,现将调查结果报告如下:     

有机农药对土壤的污染及生物修复技术研究

农药的大量使用污染了大气、水体及生态系统。有机农药以直接施用、拌种、喷撒、随降水落入等方式进入土壤。农药在土壤中会以吸附、扩散稀释和降解等几种方式发生转化，并改变土壤结构、对土壤中生物的生存及酶的活性产生影响。生物修复技术可以通过动植物、微生物及根际环境对农药污染的降解来治理土壤中的农药，是治理农药污染的一种推荐方法。     

西湖和东苕溪沉积物重金属化学形态分析

不同赋存形态重金属的环境行为和生态效应不同,水体沉积物中重金属的迁移转化及其潜在环境危害更大程度上取决于其赋存形态。本研究在西湖和东苕溪设置12个采样点采集沉积物样品,采用改进BCR分步提取法,提取了重金属污染物的4种化学形态,分别为弱酸提取态、可还原态、可氧化态及残渣态。结果表明:沉积物中Cd以弱酸提取态为主,对外界环境的变化极其敏感,并易于发生迁移转化,生态风险较高。Cu离子对有机质表现出极强的亲和力导致Cu的可氧化态含量较高也有一定的生态风险。Pb会被Fe-Mn氧化物所吸附导致Pb的可还原态含量较高,存在较高的潜在生态危害。Mn的弱酸提取态、可还原态和残渣态含量都较高,在迁移的过程中变化地较快,能够逐渐降低Mn对自然环境的危害。其他各重金属(As、Cr、Zn)则都以残渣态为主,潜在危害较低。     

我国天然水体中环境雌激素的污染现状及其生态效应研究进展

作为一种新兴的环境污染物,环境中的雌激素存在于各种介质中,并且已经被证实对生物存在危害。结合国内外的研究成果,综述了不同种类的环境雌激素在我国天然水体中污染现状以及环境雌激素对人类、水生生物和微生物的生态效应。在此基础上,对我国未来开展环境雌激素相关研究和如何应对环境雌激素污染问题进行了展望。     

论有机质在湖泊水环境中的作用

国内外学者在湖泊水环境方面开展了大量的研究,然而主要集中在各种形态氮、磷等营养盐上,对有机质的来源、循环及生态学效应的研究比较缺乏。近期研究表明：有机质是水体及沉积物中的重要组分,沉积物中有机质可经分解、矿化,释放到上覆水体,重新进入营养循环;同时,有机质对重金属及有机污染物的迁移转化有着重要影响。本文简要分析了湖泊有机质已有的研究进展,论述了有机质在湖泊水环境中的重要作用、主要技术突破及难点,指出有机质研究对水环境质量评价、污染控制和生态修复都具有重要意义。研究表明,开展有机质在水环境中循环转化、生物有效性及其与富营养化之间关系的研究,将是湖泊水环境研究领域未来的主要研究方向之一。     

Response of antibiotics and resistance genes to high-intensity and low-intensity manure management

The purpose of this study was to determine the response of antibiotics and antibiotic resistance genes (ARG) to manure management. A pilot field study was conducted using horse manure containing no antibiotics, into which chlortetracycline (CTC), tylosin (TYL), and monensin (MON) were spiked and compared to unspiked controls. Subsequently, a large-scale field study was conducted comparing manure from a dairy with minimal use of antibiotics and a feedlot with regular subtherapeutic use of antibiotics. The manures were subjected to high-intensity management (HIM) (amending, watering, and turning) and low-intensity management (LIM) (no amending, watering, or turning) and were monitored for antibiotic concentrations and levels of tetracycline ARG [tet(W) and tet(O)] using quantitative real-time polymerase chain reaction. All three antibiotics in the pilot study dissipated more rapidly in HIM manure, with half-lives ranging from 4 to 15 d, compared to LIM manure, with half-lives ranging from 8 to 30 d. Levels of tet(W) were significantly higher after 141 d of treatment, but levels of tet(O) were significantly lower in all treatments. In the large-scale study, the feedlot manure had higher initial concentrations than the dairy manure of tetracycline (TC), oxytetracycline (OTC), and CTC as well as tet(W) and tet(O). Tetracycline and OTC dissipated more rapidly in HIM manure, with half-lives ranging from 6 to 15 d, compared to LIM manure, with half-lives ranging from 7 to 31 d. After 6 mo of treatment, tet(W) and tet(O) decreased significantly in feedlot manure, whereas dairy manure required only 4 mo of treatment for similar results.     

Taxing Meat: Taking Responsibility for One’s Contribution to Antibiotic Resistance

Antibiotic use in animal farming is one of the main drivers of antibiotic resistance both in animals and in humans. In this paper we propose that one feasible and fair way to address this problem is to tax animal products obtained with the use of antibiotics. We argue that such tax is supported both by (a) deontological arguments, which are based on the duty individuals have to compensate society for the antibiotic resistance to which they are contributing through consumption of animal products obtained with the use of antibiotics; and (b) a cost-benefit analysis of taxing such animal products and of using revenue from the tax to fund alternatives to use of antibiotics in animal farming. Finally, we argue that such a tax would be fair because individuals who consume animal products obtained with the use of antibiotics can be held morally responsible, i.e. blameworthy, for their contribution to antibiotic resistance, in spite of the fact that each individual contribution is imperceptible.     

水环境中抗生素的污染现状及其去除方法研究进展

抗生素是用于防治人类和动物病菌性疾病,以及促进动物生长的一大类化学品.基于目前国内外大量使用抗生素的情况,本文针对抗生素对环境水体造成的污染,从环境水体中抗生素的来源入手,分析了抗生素在环境水体中的残留与污染水平.并讨论了目前国内外抗生素去除的研究情况,主要对常规处理技术、化学氧化、吸附3种手段进行了分析,最后对抗生素...     

Harm to Others: The Social Cost of Antibiotics in Agriculture

It has become increasingly clear that the use of antibiotics in conventionally raised livestock contributes to the emergence of antibiotic-resistant bacteria. In this paper, I argue that the harm principle of classical liberalism should guide agricultural policy in general, and the regulation of antibiotics in livestock in particular. After developing an interpretation of the harm principle, and framing the choice to produce and consume animals treated with antibiotics as a classic prisoner’s dilemma, I consider some policy responses to the problem, including a ban on the non-therapeutic use of antibiotics.     

Statewide Survey of Hormones and Antibiotics in Surface Waters of Delaware

Water‐quality surveys have confirmed the presence of hormones and antibiotics in surface waters of the United States, which may be of concern to aquatic life. We investigated the concentrations of hormones and antibiotics in surface waters of the state of Delaware to determine – how they compared against environmental thresholds, how they varied across the state, and if they were correlated with land use type. Fifty surface water locations were sampled during early spring and late summer. Water samples were initially screened with ELISA followed by analysis with LC/MS/MS. The measured ranges of hormone concentrations were: 0‐3.71 ng/l for estrone, 0‐4.65 ng/l for estrone‐3‐sulfate, and 0‐6.27 ng/l for 17β‐estradiol. The measured ranges of antibiotics were: 0‐3.30 ng/l for sulfamerazine, 0‐10.74 ng/l for sulfamethoxazole, and 0‐2.29 ng/l for tetracycline. The predicted no‐effect concentration (PNEC) for estrone was exceeded for three samples and the PNEC for 17β‐estradiol was exceeded for 11 samples. In general, concentrations and detection frequencies were lower in the summer than the spring. The highest concentrations of hormones and antibiotics were spatially distributed in agricultural and urban areas; however, the correlations between land use type and the concentrations were weak. This study was the first statewide survey of hormones and antibiotics for Delaware and provided important baseline data on these emerging contaminants.     

Antibiotic uptake by plants from soil fertilized with animal manure

Antibiotics are commonly added to animal feed as supplements to promote growth of food animals. However, absorption of antibiotics in the animal gut is not complete and as a result substantial amounts of antibiotics are excreted in urine and feces that end up in manure. Manure is used worldwide not only as a source of plant nutrients but also as a source of organic matter to improve soil quality especially in organic and sustainable agriculture. Greenhouse studies were conducted to determine whether or not plants grown in manure-applied soil absorb antibiotics present in manure. The test crops were corn (Zea mays L.), green onion (Allium cepa L.), and cabbage (Brassica oleracea L. Capitata group). All three crops absorbed chlortetracycline but not tylosin. The concentrations of chlortetracycline in plant tissues were small (2-17 ng g(-1) fresh weight), but these concentrations increased with increasing amount of antibiotics present in the manure. This study points out the potential human health risks associated with consumption of fresh vegetables grown in soil amended with antibiotic laden manures. The risks may be higher for people who are allergic to antibiotics and there is also the possibility of enhanced antimicrobial resistance as a result of human consumption of these vegetables.     

Degradation and removal methods of antibiotics from aqueous matrices--a review

Over the past few years, antibiotics have been considered emerging pollutants due to their continuous input and persistence in the aquatic ecosystem even at low concentrations. They have been detected worldwide in environmental matrices, indicating their ineffective removal from water and wastewater using conventional treatment methods. To prevent this contamination, several processes to degrade/remove antibiotics have been studied. This review addresses the current state of knowledge concerning the input sources, occurrence and mainly the degradation and removal processes applied to a specific class of micropollutants, the antibiotics. In this paper, different remediation techniques were evaluated and compared, such as conventional techniques (biological processes, filtration, coagulation, flocculation and sedimentation), advanced oxidation processes (AOPs), adsorption, membrane processes and combined methods. In this study, it was found that ozonation, Fenton/photo-Fenton and semiconductor photocatalysis were the most tested methodologies. Combined processes seem to be the best solution for the treatment of effluents containing antibiotics, especially those using renewable energy and by-products materials.     

高级氧化技术降解水体中抗生素的研究进展

抗生素是一类用于阻止和治疗微生物传染性疾病的人用和兽用药物,在人类和动物疾病治疗领域以及水产养殖业有着广泛的用途。近年来,抗生素作为一种新型污染物不断排入水体并且在水体中持续存在,对水生态环境以及人类健康造成了威胁。化学和生物等降解技术引起广泛关注,其中高级氧化技术(AOPs)由于其具有适用范围广、反应速率快、氧化能力强等特点,被成功应用到自然水体和污水中抗生素等多种有机污染物的降解。基于近年来的研究成果,综述了几种常见AOPs对抗生素的降解过程和机理,对比分析了对抗生素的降解效果,最后展望了AOPs应用于抗生素降解的研究方向和挑战。     

典型广谱抗生素的污染现状和处理技术研究进展

典型广谱抗生素是一类对生态环境和人类健康具有潜在威胁的新型污染物,其污染现状及相关处理技术受到国内外越来越多的关注。本文概述了典型广谱抗生素在环境中的污染现状,并介绍了几种针对低浓度抗生素污染原水的处理技术,包括离子交换、吸附法、膜滤法及化学氧化法等,为微污染水源中抗生素的处理提出进一步可能的研究方向。     

Sorption kinetics of chlortetracyline and tylosin on sandy loam and heavy clay soils

Antibiotics may appear in the environment when manure, sewage sludge, and other organic amendments are added to soils. There is concern that the presence of antibiotics in soils may lead to the development of antibiotic-resistant bacteria which may spread to the rest of the environment. This paper aims at evaluating the sorption kinetics of two antibiotics frequently used in pig production. The results indicate that sorption of chlortetracycline (CTC) and tylosin (TYL) in sandy loam and clay occurs very fast. More than 95% of the CTC adsorption is completed within 10 min on both soils and of TYL within 3 h. These results suggest that 24-h soil and antibiotic solution mixtures is enough for sorption studies. Also, there is less likelihood that these antibiotics will leach through soil and appear in the ground water since their sorption on soils is very high unless they are carried by soil particles through preferential flow. There was also no effect of soil sterilization on sorption kinetics of these antibiotics thus suggesting that there is minimal probability of the antibiotics degrading by microorganisms during 24- to 48-h adsorption studies.