Clear and present danger? The use of a yeast biosensor to monitor changes in the toxicity of industrial effluents subjected to oxidative colour removal treatments

Discharges of coloured effluents into surface waters provide conspicuous evidence of the impact of industry on the environment. The textile industry is an obvious candidate for sources of such discharges. Conventional treatment methods appear to alleviate this situation by removing colour, however the affect on toxicity is less obvious. The objective of this study was to examine the changes in effluent toxicity during the course of two alternative wastewater treatment methods, ozonation and electrochemical oxidation, using a novel toxicity biosensor, GreenScreen EM. The biosensor is capable of measuring both general acute toxicity (cytotoxicity), and more specifically genotoxicity, that is damage to a cell's DNA structure, replication or distribution, caused by substances that may be mutagenic and/or carcinogenic. The biosensor utilises a modified strain of the brewers yeast Saccharomyces cerevisiae, incorporating a gene encoding green fluorescent protein (GFP) linked to the inducible promoter of the DNA damage responsive RAD54 gene. Upon exposure to a genotoxin, the production of GFP is up-regulated in parallel with RAD54, and the resulting cellular fluorescence provides a measure of genotoxicity. Acute toxicity is simultaneously determined by monitoring relative total growth of the cell culture during incubation. The results presented in this paper show that a reduction in colouration does not necessarily correspond to a reduction in effluent toxicity.     

CO2泡沫混凝土碳封存潜力分析

CO₂捕集、利用与封存是碳中和技术体系的重要组成部分,混凝土在大规模吸收CO₂方面具有巨大的发展潜力.为了掌握CO₂泡沫混凝土的碳封存潜力,分析了CO₂泡沫混凝土的固碳机制,建立了CO₂泡沫混凝土固碳能力的数学模型,估算了CO₂泡沫混凝土的固碳和储碳能力.结果表明,CO₂泡沫混凝土碳封存能力的99%以上是由混凝土骨架的化学碳化方式完成的,而泡孔的储碳能力较弱;按照30%碳化率估算,我国每年生产的混凝土在全生命周期内的碳封存量平均为2.18亿t,超过大兴安岭林区森林1 a的碳汇;近5年,我国CO₂泡沫混凝土的碳封存潜力为5.80亿t ·a^-1,在煤电一体化矿区的固废和废气资源化利用方面具有很好的应用前景.CO₂泡沫混凝土在凝固前的稳定性是下一步要重点解决的技术难题.     

鄂尔多斯TSP和PM_(10)中有机氯农药的分布与来源

于2012年5月在内蒙古鄂尔多斯的东胜、纳林希里、棋盘井和上湾等4个采样点连续采集大气TSP和PM10样品,利用GC-MS分析了其中18种OCPs。结果表明:除了硫丹Ⅱ、硫丹Ⅰ和α-HCH未检出,β-HCH部分检出以外,其余14种OCPs均有100%检出。鄂尔多斯东胜、纳林希里、棋盘井和上湾TSP中∑OCPs浓度依次为2.63、9.85、5.09和6.22ng/m3;在PM10中为2.13、8.74、4.84和6.77ng/m3。∑OCPs中比重超过15%的有ADs、HCs和DDTs。TSP中∑OCPs浓度基本高于PM10中浓度,并且它们存在较好的正相关,相关系数r达到0.8846。污染源分析表明,纳林希里HCHs、CDs和DDTs可能均有外源输入。     

拟除虫菊酯农药的微波辅助无极汞灯下的降解机理研究

在水溶液中,以微波辅助无极汞灯(Microwave-Assisted Eletrodeless Discharge Mercury Lamp,MW-EDML)降解氯氰菊酯、甲氰菊酯和功夫菊酯等3种拟除虫菊酯农药(Synthetic pyrethroids,SPs),采用固相萃取(Solid Phase Extraction,SPE)富集后,用GC-MS鉴定降解产物,并根据降解产物重点探讨了SPs的降解机理。3种SPs的主要降解产物有6种,其降解途径有:酯键水解、氰基水解、脱羧、醚键断裂、氧化、苯环的羟基化以及与溶剂反应等。实验结果还表明:MW-EDML是个高效、简便的降解SPs类农药手段,可应用于其他有机污染物的降解过程。     

Corporate environmental performance expectations in the 1990s: More than just compliance

What do General Motors and Ben and Jerry's Homemade Ice Cream have in common? Both companies have endorsed the CERES principles, a model corporate code of environmental conduct developed by the Coalition for Environmentally Responsible Economies (CERES). This model code generally goes well beyond what is now typically required of industry to maintain compliance with already stringent requirements established by regulatory agencies. And the CERES principles are not the only game in town. Many other environmental initiatives have surfaced both in the United States and abroad over the past few years. This article discusses six sets of current initiatives and provides managers with a vital tool for discussing these initiatives with top management and others throughout their organizations.     

The potential effect of ISO 14000 standards on environmental audit training in the United States

Training has been an important component of the environmental audit profession since its outset some 15–20 years ago. Training and education have taken on a variety of forms—from audit texts and articles, to formal courses, to videotapes, to on-the-job training programs. These efforts have helped to advance the sophistication of environmental auditing over the past few years. Now, with the advent of the international ISO 14012 Environmental Auditor Qualification Guidelines,¹ the auditing profession in the United States and around the world likely will be transformed in the near future. In fact, many organizations are now reengineering their programs in anticipation of the emerging Guidelines. The expected transformation holds for training and education programs as well. This article suggests some of the ways in which environmental audit training is likely to be reshaped as a result of ISO 14012. Offerors of training courses and seminars would be wise to anticipate the changes and modify their programs accordingly. A quick response could provide a competitive advantage. Moreover, corporate audit program managers should conduct critical evaluations of commercial offerings to assure that the programs' contents are consistent with ISO 14012 “auditor certification” expectations.