Electrochemical degradation of amoxicillin in acidic aqueous medium using TiO2-based electrodes modified by oxides of transition metals

Environmental Science and Pollution Research - One of the most widely used antibiotics is amoxicillin (AMX), which is the most widely used in humans and animals, but it is discharged metabolically...     

广州东站室内停车场空气中羰基化合物调查

汽车尾气是大气中羰基化合物的主要来源之一.利用实验室已经建立起来的羰基化合物的检测方法,对广州东站室内停车场内空气进行了检测,结果表明,汽车尾气中检测出21种目标化合物,浓度最高的羰基化合物分别是甲醛、乙醛和丙酮,占总的羰基化合物的76.2%(质量分数).     

An overview of the environmental pollution and health effects associated with waste landfilling and open dumping

Environmental Science and Pollution Research - Landfilling is one of the most common waste management methods employed in all countries alike, irrespective of their developmental status. The most...     

Fate of pharmaceuticals and personal care products in wastewater treatment plants - Conception of a database and first results

We created a database in order to quantitatively assess the occurrence and removal efficiency of pharmaceuticals and personal care products (PPCPs) in wastewater treatment plants (WWTPs). From 117 scientific publications, we compiled 6641 data covering 184 PPCPs. Data included the concentrations of PPCPs in WWTP influents and effluents, their removal efficiency and their loads to the aquatic environment. The first outputs of our database allowed to identify the most investigated PPCPs in WWTPs and the most persistent ones, and to obtain reliable and quantitative values on their concentrations, frequency of detection and removal efficiency in WWTPs. We were also able to compare various processes and pointed out activated sludge with nitrogen treatment and membrane bioreactor as the most efficient ones.     

Eye Irritation as an Effect of Photochemical Air Pollution

One of the most annoying aspects of photochemical air pollution, particularly in the Southern California Air Basin, has been eye irritation. The most aggravating combination of driving in heavy traffic in Los Angeles, suffering from tearing and burning of the eyes together with very limited visibility, was a strong motivation for the public to demand that effective control actions be taken.     

The Nature and Sources of Haze in the Shenandoah Valley/Blue Ridge Mountains Area

In order to investigate the nature and sources of regional haze, the General Motors mobile Atmospheric Research Laboratory was used in the summer of 1980 to monitor ambient air quality in the Shenandoah Valley of northern Virginia. On the average, 92% of the total light extinction was due to scattering by particles; the remainder was due to scattering by gases and absorption by gases and particles. Sulfate aerosols were the most Important visibility-reducing species. Averaging 55% of the fine participate mass, sulfates (and associated water) accounted for 78% of the total light extinction. The second most abundant fine particulate, accounting for 29% of the fine mass, was carbon—most of which was organic. Most of the remaining particulate mass and extinction were due to crustal materials. It is estimated that 78–86% of the total light extinction was caused by anthropogenic aerosol, most of which originated in major source areas of the midwest.     

北运河沉积物/水界面上重金属迁移转化规律

分析测定了6种元素(Cr、Co、Mn、Cu、Pb、Zn)在北运河水系10个采样点水体和表层沉积物中的含量和形态分布,利用SPSS 19.0统计软件对重金属在不同形态中的含量进行相关性分析。结果显示,北运河下游重金属污染程度高于上游;Cr、Cu、Pb、Zn在底泥可提取态中所占比例相当高,多数采样点都超过10.0%。所研究的重金属多数在底泥Fe-Mn结合态与悬浮物、可交换态、硫化物和有机质结合态均存在相关性;Mn是北运河地化循环中最为活跃的元素。     

An Evaluation of Control Systems and Mass Emission Rates from Dryer-Drum Hot Asphalt Plants

The problems associated with the design and operation of appropriate air pollution control equipment for particulate emissions from dryer-drum hot asphalt plants are discussed by outlining the basic process involved, the quantities of particulate matter being emitted, and possible methods of control. The most difficult problem seems to be the emission of a fine aerosol of unburned hydrocarbons generated as a result of the simultaneous heating and mixing of the asphaltic material. From the information presented, it was concluded that in most circumstances the venturi scrubber would be the most viable alternative to meet the 0.04 gr/dscf limitation imposed by the New Source Performance Standards promulgated by the EPA.     

Understanding the External Pressure and Behavior of Commercial Banks’ Environmental Risk Management: An Empirical Study Undertaken in the Yangtze River Delta of China

The present study employed a quantitative survey to ascertain whether the external pressure of environmental risk management (ERM) on commercial banks was a contributing factor to their ERM behavior. Data was obtained using questionnaires from 204 branches of commercial banks located in the Yangtze River Delta of China. The relationship between external pressure and behavior was tested using a linear structural relations model through path analysis. The results revealed that external pressure of ERM was significantly and positively related to the behavior and that pressure from governmental regulations was the most important contributing factor in the passive feedback behavior and preventive behavior of commercial banks. The pressure from markets was the most important contributing factor in banks’ active participation behavior; the pressure from community and NGOs was the most important contributing factor in their enthusiastic behavior.     

Formation of organochlorine compounds in kraft pulp bleaching processes

The most abundant volatile organochlorine compounds (VOCCs), trichloroacetic and dichloroacetic acids and AOX, were determined in bleaching effluent and waste water from three kraft pulp mills during ClO₂ bleaching. 0.6–7.7 g of VOCCs per ton bleached pulp were formed, the most abundant being chloroform and dichloroacetic acid methyl ester. Most of the VOCCs were removed during treatment, and it was estimated that 2–30 t of VOCCs would be removed annually from activated sludge treatment plants in Finnish kraft pulp mills using elemental chlorine free bleaching, most likely by volatilization. Dichloroacetic acid was formed in considerably higher amounts than trichloroacetic acid, and both compounds were removed effectively during treatment. The formation of all organochlorine compounds decreased considerably when non-chlorinated bleaching was employed.     

Sensitivity of submersed freshwater macrophytes and endpoints in laboratory toxicity tests

The toxicological sensitivity and variability of a range of macrophyte endpoints were statistically tested with data from chronic, non-axenic, macrophyte toxicity tests. Five submersed freshwater macrophytes, four pesticides/biocides and 13 endpoints were included in the statistical analyses. Root endpoints, reflecting root growth, were most sensitive in the toxicity tests, while endpoints relating to biomass, growth and shoot length were less sensitive. The endpoints with the lowest coefficients of variation were not necessarily the endpoints, which were toxicologically most sensitive. Differences in sensitivity were in the range of 10-1000 for different macrophyte-specific endpoints. No macrophyte species was consistently the most sensitive. Criteria to select endpoints in macrophyte toxicity tests should include toxicological sensitivity, variance and ecological relevance. Hence, macrophyte toxicity tests should comprise an array of endpoints, including very sensitive endpoints like those relating to root growth.     

废轮胎热解衍生油非加氢脱硫

衍生油是废轮胎热解过程中最重要的产品之一,其最有意义的一种用途是作为燃料来得到较高的附加值.但是衍生油的硫含量较高,且具有恶臭味道,妨碍了它作为燃料的广泛应用.在管式反应器上分别考察了氧化锌、混合脱硫剂、A.D.A和MDEA+环丁砜法对废轮胎高温热解气的非加氢脱硫效果,并对不同的脱硫工艺作了简要的经济评价.结果发现,白土、陶土和石灰粉混合脱硫剂与氧化锌的热解气直接脱硫效果较好,衍生油的硫含量可降低到0.11％左右.采用油气分离的A.D.A脱硫工艺最经济.     

Risk assessment of metals and organic pollutants for herbivorous and carnivorous small mammal food chains in a polluted floodplain (Biesbosch, The Netherlands)

A risk assessment was made for a carnivorous and a herbivorous food chain in a heavily polluted natural estuary (Biesbosch), by determining the most critical pollutants and the food chain most at risk. Exposure of food chains to metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) was assessed by analyzing dietary concentrations, internal concentrations, and biomarkers of exposure. Common shrew (Sorex araneus) and bank vole (Clethrionomys glareolus) were selected as representative small mammal species for the carnivorous and herbivorous food chain, respectively, and earthworms (Lumbricus rubellus) and snails (Cepaea nemoralis) as representative prey species for the carnivorous food chain. Metals contributed most to the total risk for small mammals and earthworms. PCBs, but not PAHs, contributed to the overall risk for S. araneus at regularly flooded locations. The carnivorous food chain appeared most at risk given the higher exposure levels and bioaccumulating potency found for contaminants in S. araneus.     

Bioremediation of soil contaminated with polynuclear aromatic hydrocarbons (PAHs): a review

Polynuclear aromatic hydrocarbons (PAHs) constitute a group of priority pollutants which are present at high concentrations in the soils of many industrially contaminated sites. Criteria established for the removal or treatment or both of soils contaminated with PAHs vary widely within and between nations. The bioremediation of contaminated soils with in-situ, on-site, and bioreactor techniques is reviewed, together with the factors affecting PAH degradation. Current in-situ remediation techniques are considered ineffective for the removal of most PAHs from contaminated soil. On-site 'landforming' methods have been used successfully (and within a reasonable period of time) to degrade only those PAHs with three or fewer aromatic rings. Bioreactors have proved most effective for soil remediation, since conditions for enhanced degradation can be achieved most readily. However, bioreactors are still at the development stage, and further research is required to optimise their efficiency and economy for routine use. Degradation of the more recalcitrant high-molecular-weight PAHs is contaminated soil has not been particularly successful to date. Further research needs are identified to help develop bioremediation into a most cost-effective technology. The importance of full site assessments and treatability studies for successful application in the field is emphasised.     

The effects of various soil factors and amendments on the degradation of pesticide mixtures

Soil disposal is the most common method of handling dilute pesticide wastes. The effects of several soil factors on the degradation of a pesticide mixture were investigated. Atrazine, captan, carbaryl, 2,4-D, diazinon, fenitrothion, and trifluralin were studied under varying laboratory conditions of soil type, pH, moisture content, organic matter content, microbial activity, and pesticide concentration. Of the variables investigated, pesticide concentration was the single most important factor with degradation rates much slower at high (1000 ppm) levels of fortification than moderate (100 ppm) levels. Under most conditions, chemical degradation was at least as significant as microbial degradation. Effects of other factors varied considerably and were pesticide dependent.     

Changes in concentration of lead and cadmium in water from three rivers in Derbyshire

River water from three sites in different streams in Derbyshire was sampled during different periods within 1 year to evaluate fluctuations in cadmium and lead concentration. The results indicate that most of the cadmium was in solution, while most of the lead was associated with particles at all sites. Period of sampling appeared to have a greater effect on the concentration of cadmium and lead than flow rate: metal levels were higher in spring than in autumn. Nevertheless, the total lead concentration increased with flow rate, presumably because more particles were then brought into suspension; however, the lead concentration in the filtrate was reduced at higher flow rates, presumably due to dilution in the greater water volume. Dissolved cadmium concentration increased with rising flow rate at relatively low flow rates and was diluted at high flow rates. The data suggest that particles with which most of the lead is associated remain in suspension for a considerable time even when flow rate decreases.     

An assessment of the relationship between functional groups of weather elements and atmospheric pollution in Calgary,Canada

Nine regularly observed meteorological elements were classified into four functional groups—ventilation, energy, wet deposition and Chinook—and the contribution of each group to the air pollution process in Calgary, Canada, assessed by multiple correlation. While ventilation was the dominant process in most situations, the energy terms were the most significant during a smog. Heavy air pollution often occurred during a Chinook if the wind was weaker than 3 m s⁻¹. A linear combination of weather elements successfully separated clean from polluted air except on weekends and in very cold weather.     

Effects of iron(III)chelates on the solubility of heavy metals in calcareous soils

In this study I evaluated the effects of complexing agents on the solubility of heavy metals in an incubation experiment up to 56 days when complexing agents were applied as Fe-chelates (Fe-EDDS(S,S), Fe-EDDS(mix), Fe-EDTA and Fe-EDDHA) on calcareous soils at a level sufficient to correct Fe chlorosis (0.1 mmol kg⁻¹). Of these ligands, EDDHA was the most efficient in keeping Fe in water-soluble form, and EDDS increased the solubility of Cu and Zn most, and only EDTA increased the solubility of Cd and Pb. EDTA increased the solubility of Ni steadily during the incubation period, equalling about 5-8% of the added EDTA concentration. [S,S]-EDDS was biodegraded within 56 days, whereas EDDS(mix) was less biodegradable. Ni-chelates were the most recalcitrant against biodegradation. The study shows that even a moderate input of chelates to soil increases the solubility of toxic heavy metals and their risk of leaching.     

Identification of Community Odor Problems by Use of an Observer Corps

To evaluate the major odors affecting a community, approximately 120 high school students recorded odor observations. Simultaneous odor observations were made three times daily for 14 consecutive days each in a fall and spring survey. The observers were tested for olfactory sensitivity, and population characteristics were recorded for analyses of the human variables. These data were analyzed to show the areas most severely affected, the major objectionable odor types, the time when odors were most frequent, and the associated weather parameters. A critique of the procedures employed and the results of the survey are presented.     

Trace metals assessment in water, sediment, mussel and seagrass species--validation of the use of Posidonia oceanica as a metal biomonitor

The accumulation of trace metals (Cd, Co, Cr, Hg, Ni and Pb) was measured in water, sediment, the mussel Mytilus galloprovincialis and the seagrass Posidonia oceanica. Samples were collected in three locations of the north-western Mediterranean (Canari, Livorno and Porto-Torres) which present different levels and sources of human impact. Analyses in the different compartments (water, sediment, M. galloprovincialis and P. oceanica) have allowed to identify Canari as the most Cd, Co, Cr and Ni contaminated site; Livorno as the most Hg contaminated and Porto-Torres as the most Pb contaminated. Furthermore, for the first time, metal concentrations found in P. oceanica have been compared with those found in the water column, in the sediment and in the recognized metal bio-indicator species M. galloprovincialis and the results obtained have led to the same conclusions. Thus, this study allows to validate the use of P. oceanica as metal biomonitor of coastal waters.