Showing papers in "Environmental Science and Pollution Research in 2011"

Hexachlorocyclohexane (HCH) as new Stockholm Convention POPs--a global perspective on the management of Lindane and its waste isomers.

Abstract: Purpose Hexachlorocyclohexane (HCH) isomers (α-, β- and γ- (Lindane)) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention, and therefore, the legacy of HCH and Lindane production became a contemporary topic of global relevance. This article wants to briefly summarise the outcomes of the Stockholm Convention process and make an estimation of the amount of HCH waste generated and dumped in the former Lindane/HCH-producing countries.

Applications of polychlorinated biphenyls.

Abstract: Background, aim, and scope In the 50 years or so that polychlorinated biphenyls (PCBs) were manufactured in the USA and elsewhere, they were widely used in numerous applications because of their desirable properties. The purpose of this paper is to review and summarize in one place the factual information about the uses of PCBs, as well as to correct some misconceptions that have arisen over the years. The focus is on applications in the USA for which there is ample documentation. However, use patterns were probably similar worldwide.

Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide nanoparticles: effect of particle size, solid concentration, and exhaustion

Abstract: Adsorption of metals (Pb, Cd, Cu, Ni, Zn) to TiO2 nanoparticles and bulk particles was examined for use as a contaminant removal substrate as a function of particle size, sorbent concentration, and exhaustion. Adsorption experiments were conducted with 0.01, 0.1, and 0.5 g/L nanoparticles in a pH 8 solution and in spiked San Antonio tap water. When results were normalized by mass, nanoparticles adsorbed more than the bulk particles but when results were surface-area normalized, the opposite was observed. The adsorption data shows the ability of the TiO2 nanoparticles to remove Pb, Cd, and Ni from solution with similar adsorption at 0.1 and 0.5 g/L. Adsorption kinetics for all metals tested was described by a modified first order rate equation with the nanoparticles having a faster rate of adsorption than the bulk particles. The nanoparticles were able to simultaneously removal multiple metals (Zn, Cd, Pb, Ni, Cu) from both pH 8 solution and spiked San Antonio tap water. Exhaustion experiments showed that both the nanoparticles and bulk particles were exhausted at pH 6 but at pH 8, exhaustion did not occur for the nanoparticles. Comparison of K d, distribution coefficient, with other literature showed that the nanoparticles were better sorbents than other metal oxide nanoparticles and a commercial activated carbon.

Behavioural ecotoxicology, an “early warning” signal to assess environmental quality

Abstract: Background In this review, the position of behavioural ecotoxicology within the available means to assess the status of marine environments is described as filling the gap for the needed “early warning” signals. A few examples of studies performed since the 1960s are discussed to highlight the sensitivity of these approaches in investigating the effects of chemicals, including priority pollutants and emerging contaminants, relative to conventional toxicity tests measuring survival.

Source apportionment of PM 10 and PM 2.5 at multiple sites in the strait of Gibraltar by PMF: impact of shipping emissions

Abstract: The impact of shipping emissions on urban agglomerations close to major ports and vessel routes is probably one of the lesser understood aspects of anthropogenic air pollution. Little research has been done providing a satisfactory comprehension of the relationship between primary pollutant emissions, secondary aerosols formation and resulting air quality. In this study, multi-year (2003–2007) ambient speciated PM10 and PM2.5 data collected at four strategic sampling locations around the Bay of Algeciras (southern Spain), and positive matrix factorisation model were used to identify major PM sources with particular attention paid to the quantification of total shipping emissions. The impact of the emissions from both the harbour of Algeciras and vessel traffic at the Western entrance of Mediterranean Sea (Strait of Gibraltar) were quantified. Ambient levels of V, Ni, La and Ce were used as markers to estimate PM emitted by shipping. Shipping emissions were characterised by La/Ce ratios between 0.6 and 0.8 and V/Ni ratios around 3 for both PM10 and PM2.5. In contrast, elevated La/Ce values (1–5) are attributable to emissions from refinery zeolitic fluid catalytic converter plant, and low average V/Ni values (around 1) result mainly from contamination from stainless steel plant emissions. The direct contribution from shipping in the Bay of Algeciras was estimated at 1.4–2.6 μg PM10/m3 (3–7%) and 1.2–2.3 μg PM2.5/m3 (5–10%). The total contribution from shipping (primary emissions + secondary sulphate aerosol formation) reached 4.7 μg PM10/m3 (13%) and 4.1 μg PM2.5/m3 (17%).

Polyfluorinated surfactants (PFS) in paper and board coatings for food packaging.

Abstract: In this study, we explore the identity of a range of polyfluorinated surfactants (PFS) used for food contact materials, primarily to impart oil and water repellency on paper and board. PFS are of interest, as they can be precursors of poly- and perfluorinated alkyl substances (PFAS), of which several are persistent and are found worldwide in human blood and in the environment. To determine the elemental composition of PFS, we combined information from patents, chemical suppliers and analyses of industrial blends using ultra performance liquid chromatography-negative electrospray ionisation quadrupole time-of-flight mass spectrometry. At a high pH of 9.7, both non-ionic and anionic PFS were ionised and were recognised by negative mass defects of exact masses, and neutral fragment losses of n × 20 or n × 100 Da. More than 115 molecular structures were found in industrial blends from the EU, US and China, belonging to the groups of polyfluoroalkyl-mono- and di-ester phosphates (monoPAPS, diPAPS and S-diPAPS), -ethoxylates, -acrylates, -amino acids, -sulfonamide phosphates and -thio acids, together with residuals and synthesis byproducts. In addition, a number of starting materials such as perfluorooctane sulfonamide N-alkyl esters were analysed. Di- and trialkylated PAPS and S-diPAPS were found in migrates from European food contact materials. This study highlights the need to monitor for more types of PFS in order to map the sources of PFAS in humans and the environment.

Still present after all these years: persistence plus potential toxicity raise questions about the use of atrazine

Abstract: As one of the worlds’ most heavily applied herbicides, atrazine is still a matter of controversy. Since it is regularly found in ground and drinking water, as well as in sea water and the ice of remote areas, it has become the subject of continuous concern due to its potential endocrine and carcinogenic activity. Current findings prove long-held suspicions that this compound persists for decades in soil. Due to the high amount applied annually all over the world, the soil burden of this compound is considered to be tremendous, representing a potential long-term threat to the environment. The persistence of chemicals such as atrazine has long been underestimated: Do we need to reconsider the environmental risk?

Microbial communities to mitigate contamination of PAHs in soil—possibilities and challenges: a review

Abstract: Background, aim, and scope Although highly diverse and specialized prokaryotic and eukaryotic microbial communities in soil degrade polycyclic aromatic hydrocarbons (PAHs), most of these are removed slowly. This review will discuss the biotechnological possibilities to increase the microbial dissipation of PAHs from soil as well as the main biological and biotechnological challenges.

Heavy metal contamination and risk assessment in water, paddy soil, and rice around an electroplating plant

Abstract: The objective of this paper is to assess the impact of long-term electroplating industrial activities on heavy metal contamination in agricultural soils and potential health risks for local residents. Water, soil, and rice samples were collected from sites upstream (control) and downstream of the electroplating wastewater outlet. The concentrations of heavy metals were determined by an atomic absorption spectrophotometer. Fractionation and risk assessment code (RAC) were used to evaluate the environmental risks of heavy metals in soils. The health risk index (HRI) and hazard index (HI) were calculated to assess potential health risks to local populations through rice consumption. Hazardous levels of Cu, Cr, and Ni were observed in water and paddy soils at sites near the plant. According to the RAC analysis, the soils showed a high risk for Ni and a medium risk for Cu and Cr at certain sites. The rice samples were primarily contaminated with Ni, followed by Cr and Cu. HRI values >1 were not found for any heavy metal. However, HI values for adults and children were 2.075 and 1.808, respectively. Water, paddy soil, and rice from the studied area have been contaminated by Cu, Cr, and Ni. The contamination of these elements is related to the electroplating wastewater. Although no single metal poses health risks for local residents through rice consumption, the combination of several metals may threaten the health of local residents. Cu and Ni are the key components contributing to the potential health risks.

Isotopes for improved management of nitrate pollution in aqueous resources: review of surface water field studies.

Abstract: Environmental agencies have to take measures to either reduce discharges and emissions of nitrate or to remediate nitrate-polluted water bodies where the nitrate concentrations exceed threshold values. Isotope data can support the identification of nitrate pollution sources and natural attenuation processes of nitrate. This review article gives an overview of the information available to date regarding nitrate source apportionment in surface waters with the ambition to help improving future studies. Different isotope approaches in combination with physicochemical and hydrological data can successfully be used in source apportionment studies. A sampling strategy needs to be developed based on possible nitrate sources, hydrology and land use. Transformations, transport and mixing processes should also be considered as they can change the isotope composition of the original nitrate source. Nitrate isotope data interpreted in combination with hydrological and chemical data provide valuable information on the nitrate pollution sources and on the processes nitrate has undergone during its retention and transport in the watershed. This information is useful for the development of an appropriate water management policy.

Forecasting hourly PM(10) concentration in Cyprus through artificial neural networks and multiple regression models: implications to local environmental management.

Abstract: In the present work, two types of artificial neural network (NN) models using the multilayer perceptron (MLP) and the radial basis function (RBF) techniques, as well as a model based on principal component regression analysis (PCRA), are employed to forecast hourly PM10 concentrations in four urban areas (Larnaca, Limassol, Nicosia and Paphos) in Cyprus. The model development is based on a variety of meteorological and pollutant parameters corresponding to the 2-year period between July 2006 and June 2008, and the model evaluation is achieved through the use of a series of well-established evaluation instruments and methodologies. The evaluation reveals that the MLP NN models display the best forecasting performance with R 2 values ranging between 0.65 and 0.76, whereas the RBF NNs and the PCRA models reveal a rather weak performance with R 2 values between 0.37-0.43 and 0.33-0.38, respectively. The derived MLP models are also used to forecast Saharan dust episodes with remarkable success (probability of detection ranging between 0.68 and 0.71). On the whole, the analysis shows that the models introduced here could provide local authorities with reliable and precise predictions and alarms about air quality if used on an operational basis.

Antibiotic contaminants in coastal wetlands from Vietnamese shrimp farming.

Abstract: Background and purpose Shrimp culture has been expanded rapidly in recent years in coastal wetland zone of Vietnam due to favorable natural conditions. However, this industry has caused several negative impacts to the environment. One of the critical issues is the excessive application of antibiotics including human medicines. These chemicals could be released from shrimp ponds and then accumulated and contaminated of the ecosystem. This review article discusses a whole range of findings that address various aspects of the usage, occurrence and potentially environmental risks of antibiotics released from shrimp farming, with emphasis on the South Vietnam coastal wetland.

Investigation of ZnO nanoparticles' ecotoxicological effects towards different soil organisms

Abstract: Nanomaterials have widespread applications in several industrial sectors. ZnO nanoparticles (NPs) are among the most commonly used metal oxide NPs in personal care products, coating and paints. However, their potential toxicological impact on the environment is largely unexplored. The aim of this work was to evaluate whether ZnO nanoparticles exert toxic and genotoxic effects upon terrestrial organisms: plants (Lepidium sativum, Vicia faba), crustaceans (Heterocyipris incongruens), insects (Folsomia candida). To achieve this purpose, organisms pertaining to different trophic levels of the soil ecosystem have been exposed to ZnO NPs. In parallel, the selected soil organisms have been exposed to the same amount of Zn in its ionic form (Zn2+) and the effects have been compared. The most conspicuous effect, among the test battery organisms, was obtained with the ostracod H. incongruens, which was observed to be the most sensitive organism to ZnO NPs. The root elongation of L. sativum was also mainly affected by exposure to ZnO NPs with respect to ZnCl2, while collembolan reproduction test produced similar results for both Zn compounds. Slight genotoxic effects with V. faba micronucleus test were observed with both soils. Nanostructured ZnO seems to exert a higher toxic effect in insoluble form towards different terrestrial organisms with respect to similar amounts of zinc in ionic form.

Uptake and distribution of metals by water lettuce ( Pistia stratiotes L.)

Abstract: Water quality impairment by heavy metal contamination is on the rise worldwide. Phytoremediation technology has been increasingly applied to remediate wastewater and stormwater polluted by heavy metals. Laboratory analysis and field trials were conducted to evaluate the uptake of metals (Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) by an aquatic plant, water lettuce (Pistia stratiotes L.), and metal distribution in the plant. The growth of water lettuce reduced Al, Fe, and Mn concentrations in water by >20%, K and Cu by >10%, and Ca, Mg, Zn, and Na to a lesser extent. A larger proportion of Ca, Cd, Co, Fe, Mg, Mn, and Zn was adsorbed or deposited on the external root surfaces while more Al, Cr, Cu, Ni, and Pb were absorbed and accumulated within the roots. Water lettuce has a great ability in concentrating metals from its surrounding water with a concentration factor (CF) ≥102. The bio-concentration factor (BCF), which excludes the part on the root surfaces, is a more appropriate index than the CF for the differentiation of hyperaccumulation, accumulation, or non-accumulation plants for metals. Water lettuce is a hyperaccumulator for Cr, Cu, Fe, Mn, Ni, Pb, and Zn and can be applied for the remediation of surface waters. Further study on the bioavailability of metals in the water lettuce is needed for the beneficial use of metal-enriched plant biomass.

Indoor air quality differences between urban and rural preschools in Korea

Abstract: Background, aims, and scope Preschool indoor air quality (IAQ) is believed to be different from elementary school or higher school IAQ and preschool is the first place for social activity. Younger children are more susceptible than higher-grade children and spend more time indoors. The purpose of this study was to compare the indoor air quality by investigating the concentrations of airborne particulates and gaseous materials at preschools in urban and rural locations in Korea.

Exploring the metal phytoremediation potential of three Populus alba L. clones using an in vitro screening.

Abstract: Purpose This work was planned for providing a useful screening tool for the selection of Populus alba clones suitable for phytoremediation techniques. To this aim, we investigated variation in arsenic, cadmium, copper, and zinc tolerance, accumulation and translocation in three poplar clones through an in vitro screening. Poplars have been widely proposed for phytoremediation, as they are adaptable to grow on contaminated areas and able to accumulate metals. The investigation of possible differences among poplar clones in metal tolerance and accumulation deserves to be deeply studied and exploited for the selection of the more suitable tool for phytoremediation purposes.

Inventory of heavy metal content in organic waste applied as fertilizer in agriculture: evaluating the risk of transfer into the food chain

Abstract: In this work, an environmental risk assessment of reusing organic waste of differing origins and raw materials as agricultural fertilizers was carried out. An inventory of the heavy metal content in different organic wastes (i.e., compost, sludge, or manure) from more than 80 studies at different locations worldwide is presented. The risk analysis was developed by considering the heavy metal (primarily Cd, Cu, Ni, Pb, and Zn) concentrations in different organic residues to assess their potential environmental accumulation and biotransfer to the food chain and humans. A multi-compartment model was used to estimate the fate and distribution of metals in different environmental compartments, and a multi-pathway model was used to predict human exposure. The obtained hazard index for each waste was concerning in many cases, especially in the sludge samples that yielded an average value of 0.64. Among the metals, Zn was the main contributor to total risk in all organic wastes due to its high concentration in the residues and high biotransfer potential. Other more toxic metals, like Cd or Pb, represented a negligible contribution. These results suggest that the Zn content in organic waste should be reduced or more heavily regulated to guarantee the safe management and reuse of waste residues according to the current policies promoted by the European Union.

Toxic effect of tetracycline exposure on growth, antioxidative and genetic indices of wheat (Triticum aestivum L.)

Abstract: Introduction More attention has been paid to tetracycline contamination in view of its rapid increasing concentration in the environment Therefore, it is important to set up rapid, simple, and accurate methods for monitoring tetracycline ecotoxicity

Nitrogen-efficient rice cultivars can reduce nitrate pollution

Abstract: Environmental pollution by un-utilized nitrogenous fertilizer at the agricultural field is one of the key issues of the day. Rice-based cropping system, the mainstay of Indian agriculture, is one of the main sources of unused N-fertilizer since rice utilizes only 30–40% of total applied N, and the rest goes to waste and creates environmental as well as economic loss. Identification of rice genotypes that can grow and yield well at low nitrogen levels is highly desirable for enhancement of nitrogen use efficiency (NUE). In the present study, we have identified large variability in the NUE of rice cultivars on the basis of plant with low, medium, and high levels of N in nutrient solution. To establish the basis of this wide variability in NUE, nitrate uptake kinetics and enzymes of nitrate assimilation were studied. The data of nitrate uptake kinetics revealed that the nitrate uptake is mediated by low-affinity transporter system (LATS) in N-inefficient rice cultivars and by both LATS and high-affinity transporter systems (HATS) in N-efficient genotypes. Activities of nitrate reductase, nitrite reductase, glutamine synthetase, glutamate synthase, and the soluble protein content were found to be increased in moderately N-efficient and low N-efficient cultivars with increase in external supply of nitrogen. However, a non-significant decrease in these enzymes was recorded in high N-efficient cultivars with the increase in N supply. This study suggests that the HATS, high NR, and glutamine synthetase activity and the soluble protein content distribution have a key role in N efficiency of rice genotypes. These parameters may be considered in breeding and genetic engineering programs for improving the NUE of rice, which might be helpful in reducing the fertilizer loss, hence decreasing environmental degradation and improving crop productivity through improvement of nitrogen utilization efficiency in rice.

Chlorpyrifos degradation by the cyanobacterium Synechocystis sp. strain PUPCCC 64.

Abstract: Indiscriminate use of insecticides leads to environmental problems and poses a great threat to beneficial microorganisms. The aim of the present work was to study chlorpyrifos degradation by a rice field cyanobacterium Synechocystis sp. strain PUPCCC 64 so that the organism is able to reduce insecticide pollution in situ. The unicellular cyanobacterium isolated and purified from a rice field was identified by partial 16S rRNA gene sequence as Synechocystis sp. strain PUPCCC 64. Tolerance limit of the organism was determined by studying its growth in graded concentrations (2.5–20 mg/L) of chlorpyrifos. Chlorpyrifos removal was studied by its depletion from the insecticide supplemented growth medium, and its biodegradation products were identified in the cell extract, biomass wash, and growth medium. The organism tolerated chlorpyrifos up to 15 mg/L. Major fraction of chlorpyrifos was removed by the organism during the first day followed by slow uptake. Biomass, pH, and temperature influenced the insecticide removal and the organism exhibited maximum chlorpyrifos removal at 100 mg protein/L biomass, pH 7.0, and 30°C. The cyanobacterium metabolized chlorpyrifos producing a number of degradation products as evidenced by GC-MS chromatogram. One of the degradation products was identified as 3,5,6-trichloro-2-pyridinol. Present study reports the biodegradation of chlorpyrifos by Synechocystis sp. Biodegradation of the insecticide by the cyanobacterium is significant as it can be biologically removed from the environment. The cyanobacterium may be used for bioremediation of chlorpyrifos-contaminated soils.

Trace analysis of persistent toxic substances in the main stream of Jiangsu section of the Yangtze River, China.

Abstract: The Jiangsu section of the Yangtze River is the downstream of the whole river, serving as an important drinking water source. Persistent toxic substances (PTS), from the industries such as automobile, textile, chemical, and electronic production, are not listed in the National Standard yet and not monitored and controlled. However, pollution of PTS can threaten the environment and human health. In order to understand the pollution status of the PTS contamination and recommend future rationalization of countermeasure, the PTS including organochlorine pesticides (OCPs), polyaromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs), and phthalates (PAEs) were investigated. Samples were collected at 15 sites from five main stream sections of the Yangtze River in Jiangsu Province. PTS were extracted using solid phase extract method. The analysis of OCPs, PCBs was performed using GC/ECD and PAHs, PAEs was performed by GC/MS. The method detection limits are low and the recoveries are from 58.1% to 110.3%. The total concentrations of OCPs, PCBs, PAHs, and PAEs were 0.27∼2.15 ng l−1, <0.21∼44.4 ng l−1, 0.012∼3.576 μg l−1 and 0.178∼1.474 μg l−1, respectively. γ-HCH, PCB28, PCB101, phenanthrene, anthracene, di-n-butyl phthalate, diethyl phthalate, and di-(2-ethylhexyl) phthalate are the major detected PTS. The concentration of most of the PTS was below the environmental quality standards for surface water of China. The pollution status of OCPs, PCBs, PAHs, and PAEs were analyzed. PTS contamination levels of the five main stream sections were relatively low.

Evaluation of hexachlorocyclohexane contamination from the last lindane production plant operating in India.

Abstract: Purpose α-Hexachlorocyclohexane (HCH), β-HCH, and lindane (γ-HCH) were listed as persistent organic pollutants by the Stockholm Convention in 2009 and hence must be phased out and their wastes/stockpiles eliminated. At the last operating lindane manufacturing unit, we conducted a preliminary evaluation of HCH contamination levels in soil and water samples collected around the production area and the vicinity of a major dumpsite to inform the design of processes for an appropriate implementation of the Convention.

Detection of human-induced environmental disturbances in a show cave

Abstract: We investigated the effects of human-induced disruption in a subterranean stable environment containing valuable Palaeolithic paintings and engravings (Ardales Cave, Southern Spain) using a double analytical approach. An environmental monitoring system was installed in the cave to record temperature, relative humidity, carbon dioxide (CO2) and radon (222Rn) concentrations in air. In the same stations, an aerobiological sampling was conducted to quantify the level of airborne microorganisms. The combination of different methods allowed us to detect the extent of human-induced changes, confirming that these can be very hazardous in certain cave areas that should be apparently outside the scope of human disturbances, either by their remoteness to the visitor entrance or by being briefly visited. The detection of evident anomalies in the environmental parameters and airborne microorganism concentration in the cave area housing the high density of paintings and engravings helps to control human disturbances and supports the direct application of this double approach for cave management purposes.

Calcium invigorates the cadmium-stressed Brassica napus L. plants by strengthening their photosynthetic system.

Abstract: Cadmium (Cd) in plants interrupts numerous metabolic processes and reduces the water and nutrient uptake that cause chlorosis, growth retardation, and ultimately plant death. Response of Brassica napus L. to calcium (Ca) enrichment in growth medium for reducing Cd toxicity stress by strengthening the photosynthesis organelles and their functionality was explored in this study. B. napus seedlings of two cultivars (ZS 758 and ZS 72) were exposed to Cd toxicity at 500 μM in hydroponics, and it was ameliorated with Ca at 2.0 mM. The study included determinations and evaluations pertaining to physiological attributes of plant growth, chlorophyll, and photosynthesis. Cadmium stress significantly depressed the seedling growth and reduced photosynthetic rate (Pn), stomatal conductivity (Gs), and transpiration rate (Tr). Further, Cd toxicity markedly decreased the electron transport rate of PSII, effective quantum yield of photochemical energy conversion in PSII [Y(II)], photosynthetic active radiation, coefficient of photochemical quenching (qP), and chlorophyll fluorescence decrease ratio (RFd). Addition of Ca in Cd-stressed plants antagonized the toxicity effects on all the above-mentioned attributes. Calcium amendment also reversed the Cd stress-induced increase in intercellular CO2 concentration (Ci) and non-photochemical quenching, and countered the Cd accumulation in seedlings. This study suggests that Ca2+ in the proximity of plasma membrane is proficient in alleviating Cd toxicity by reducing the cell-surface negativity and competing for Cd2+ ion influx. Consequently, both the plant growth and activity of diurnal photosynthetic system remain the least altered under Cd-provoked toxicity stress.

Influence of organic waste and residue mud additions on chemical, physical and microbial properties of bauxite residue sand

Abstract: Background, aim and scope In an alumina refinery, bauxite ore is treated with sodium hydroxide at high temperatures and pressures and for every tonne of alumina produced, about 2 tonnes of alkaline, saline bauxite processing waste is also produced. At Alcoa, a dry stacking system of disposal is used, and it is the sand fraction of the processing waste that is rehabilitated. There is little information available regarding the most appropriate amendments to add to the processing sand to aid in revegetation. The purpose of this study was to investigate how the addition of organic wastes (biosolids and poultry manure), in the presence or absence of added residue mud, would affect the properties of the residue sand and its suitability for revegetation.

Application of an indicator based on taxonomic relatedness of ciliated protozoan assemblages for marine environmental assessment

Abstract: Ciliated protozoa play important roles in aquatic ecosystems especially regarding their functions in micro-food web and have many advantages in environmental assessment compared with most other eukaryotic organisms. The aims of this study were focused on analyzing the application of an indicator based on taxonomic relatedness of ciliated protozoan assemblages for marine environmental assessment. The spatial taxonomic patterns and diversity measures in response to physical–chemical variables were studied based on data from samples collected during 1-year cycle in the semi-enclosed Jiaozhou Bay, northern China. The spatial patterns of ciliate communities were significantly correlated with the changes of environmental status. The taxonomic distinctness (Δ*) and the average taxonomic distinctness (Δ+) were significantly negatively correlated with the changes of nutrients (e.g., nitrate nitrogen and soluble active phosphate; P < 0.05). Pairwise indices of Δ+ and the variation in taxonomic distinctness (Λ+) showed a decreasing trend of departure from the expected taxonomic breadth in response to the eutrophication stress and anthropogenic impact. The taxonomic relatedness (especially the pairwise Δ+ and Λ+) indices of ciliate communities are robust as an indicator with scientifically operational value in marine environmental assessment.

Bioremediation and reclamation of soil contaminated with petroleum oil hydrocarbons by exogenously seeded bacterial consortium: a pilot-scale study.

Abstract: Purpose Spillage of petroleum hydrocarbons causes significant environmental pollution. Bioremediation is an effective process to remediate petroleum oil contaminant from the ecosystem. The aim of the present study was to reclaim a petroleum oil-contaminated soil which was unsuitable for the cultivation of crop plants by using petroleum oil hydrocarbon-degrading microbial consortium.

Response of denitrification genes nirS , nirK , and nosZ to irrigation water quality in a Chinese agricultural soil

Abstract: Purpose Denitrification is an important biochemical process in global nitrogen cycle, with a potent greenhouse gas product N(2)O. Wastewater irrigation can result in the changes of soil properties and microbial communities of agricultural soils. The purpose of this study was to examine how the soil denitrification genes responded to different irrigation regimes. Materials and methods Soil samples were collected from three rural districts of Beijing (China) with three different irrigation regimes: clean groundwater (CW), reclaimed water (RW), and wastewater (WW). The abundance and diversity of three denitrification microbial genes (nirS, nirK, and nosZ) were examined by real-time polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) molecular approaches. Results and discussion The abundance of nirS in the WW treatment was higher than that in the CW treatment, and no significant difference was found between the RW and CW or WW treatments. The abundance of nirK gene of the RW and WW treatments was higher than that of the CW treatment. There was no difference for nosZ gene among the three treatments. Correspondence analysis based on the DGGE profiles showed that there was no obvious difference in the nosZ gene composition, but nirS and nirK genes changed with different irrigation regimes. Conclusions Irrigation with unclean water sources enhanced the soil NO(3)(-) content and changed the abundance and composition of soil denitrifiers, and different functional genes had different responses. Irrigation with unclean water sources increased the abundance of nirK gene and changed the community structures of nirS and nirK genes, while nosZ gene was relatively stable in the soil. These results could be helpful to explore the mechanisms of the variation of denitrification processes under long-term wastewater irrigation and partially explain the reason of more N(2)O output in the field with wastewater irrigation.

The endocrine disrupting potential of sediments from the Upper Danube River (Germany) as revealed by in vitro bioassays and chemical analysis

Abstract: Introduction The present study was part of a comprehensive weight-of-evidence approach with the goal of identifying potential causes for the declines in fish populations, which have been observed during the past decades in the Upper Danube River.

The OECD validation program of the H295R steroidogenesis assay: Phase 3. Final inter-laboratory validation study

Abstract: In the original article wrong unites were quoted in Table 3 (page 508) and Table 4 (page 510) as well as in the paragraph 3.2 Core chemical exposure experiments on page 509. Also in paragraph 2.3 Selection and testing of chemicals the link to the Supplemental Materials (ESM) was missing.