Study on removal of silver and polyethylene terephthalate from exposed radiography films using enzyme protease

Journal of Material Cycles and Waste Management - In the proposed method, crude enzymes extracted from waste dry leaves of 15 different plants showing protease activity were used for removal of...     

Biomanagement of petrochemical sludge using an exotic earthworm Eudrilus eugineae

Petrochemical industry have severe problem in disposing effluent and semisolid sludge despite repeated recycling. It requires further treatment prior to disposal of sludge. In recent years biological treatment methods received much attention and considered as an efficient low-cost treatment. One such method is vermiculture treatment The end product of vermicompost is rich in essential micro and macronutrients along with microorganisms in a very simple form. Adding cast, not only improves the soil structure and fertility but also leads to improvement in overall plant growth and thus increase their yield. The present study was carried out to dispose the petrochemical sludge biologically using an exotic earthworm Eudrilus eugineae. The petrochemical sludge at various concentrations 25, 50 and 75% were subjected to vermicomposting treatment for a period of 60 days. During the period of study, data were collected on life form of earthworm and chemical analysis of the sludge before and after treatment. The microbial analysis was carried out fortnightly. The results indicate that 25 and 50% concentration of sludge was ideal for the vermicomposting, whereas the higher concentration inhibits the vermicomposting.     

Impacts of microwave pretreatments on the semi-continuous anaerobic digestion of dairy waste activated sludge

Microwave (MW) irradiation is one of the new and possible methods used for pretreating the sludge. Following its use in different fields, this MW irradiation method has proved to be more appropriate in the field of environmental research. In this paper, we focused on the effects of MW irradiation at different intensities on solubilization, biodegradation and anaerobic digestion of sludge from the dairy sludge. The changes in the soluble fractions of the organic matter, the biogas yield, the methane content in the biogas were used as control parameters for evaluating the efficiency of the MW pretreatment. Additionally, the energetic efficiency was also examined. In terms of an energetic aspect, the most economical pretreatment of sludge was at 70% intensity for 12 min irradiation time. At this, COD solubilization, SS reduction and biogas production were found to be 18.6%, 14% and 35% higher than the control, respectively. Not only the increase in biogas production was investigated, excluding protein and carbohydrate hydrolysis was also performed successfully by this microwave pretreatment even at low irradiation energy input. Also, experiments were carried out in semi continuous anaerobic digesters, with 3.5 L working volume. Combining microwave pretreatment with anaerobic digestion led to 67%, 64% and 57% of SS reduction, VS reduction and biogas production higher than the control, respectively.     

Biosorption of Cu (II) ions by indigenous copper-resistant bacteria isolated from polluted coastal environment

The concentrations of copper in water and sediment samples of Cuddalore coastal area, Tamil Nadu, India were examined. The isolation, characterization, screening, and metal sorption capabilities of copper-resistant bacteria (CURB) also were investigated. Biosorption capabilities and growth time varied among the resistant isolates. All isolates reduced more than 80% of copper from copper-treated broth. However, Bacillus cereus CURB-4 strain absorbed more copper ions (99.9%) than other resistant isolates. Changes in structural group position and synthesis of extracellular polysaccharides (EPS) of CURB-4 strain under copper stress and controlled conditions also were examined. Under copper stress condition, CURB-4 produced more EPS (71 ± 0.6%) compared to control conditions (66 ± 0.4%). Fourier transform infrared spectroscopy revealed that the changes in functional group position of EPS were observed in stressed condition. Overall, synthesis of EPS in bacteria is a protective barrier against environmental stress.     

Synthesis of nickel nanoparticles by chemical and green route and their comparison in respect to biological effect and toxicity

Recent reports demonstrated an increase in the synthesis of nanoparticles (NP) and its applications. The chemical preparation of NP may be harmful. Thus, in this study, the biological activity and toxicology of nickel nanoparticles (NiNP) synthesized through chemical and green routes were compared. Chemical synthesis of NiNP was mediated by polyethylene glycol and hydrazine hydrate as stabilizing and reducing agent, respectively. Desmodium gangeticum aqueous root extract was used to prepare NiNP without any stabilizing and reducing agent. Nickel nanoparticles synthesized by both methods were characterized (ultraviolet–visible spectroscopy, X-ray diffractrometry, Fourier transform infrared spectroscopy, zeta potential and vibrating sample magnetometer) and compared. There was no major significant difference in the nature of the NP prepared by both methods. However, green synthesized NiNP showed reduced size and better monodispersity compared to chemical synthesized one. Free radical scavenging activities and antibacterial activities of NiNP prepared by chemical and green route suggest that these NP, prepared by green route possess reliable antioxidant and antibacterial activity. Evaluation of toxicity in animal and cell line suggests that NiNP synthesized by green route are nontoxic.     

Public preferences for visual quality and management in the Kackar Mountains National Park (Turkey)

There are 37 national parks in Turkey, encompassing the most important mountain ecosystems, with high biological, natural, cultural and historical diversity. These parks also have aesthetic and recreational potential, and are valuable components within the country's nature protection programmes. Globally, a landscape can be regarded as the face of an ecosystem and constitutes a relationship between natural structure and visual features. There have been several studies on whether visual quality can provide indicators for landscape planning. Visual quality can also be assessed as a manifesto for community participation. This paper attempts to extend the understanding of visual quality assessment for national parks, using the Kackar Mountains National Park (KMNP) in north-eastern Turkey as an example. A detailed survey of visual quality preferences, landscape factors (10 main and 40 sub-factors) and semantic factors (naturalness, variety, fascination, vividness, unity, interesting and exciting) affecting these preferences was made using 30 represenative slides selected from the park. The highest preference was found to be 6.54, while the lowest was 2.30. Regression analysis enabled us to determine the relationship between visual quality and visual landscape attributes. The R2 value for naturalness was 0.482, while naturalness together with lake and fog percentage was 0.641. The assessment of preferences for the studied views in various landscape units can be evaluated and used for land-use decisions and future planning in KMNP.     

Use of sub-micron sized resin particles for removal of endocrine disrupting compounds and pharmaceuticals from water and wastewater

Endocrine disrupting compounds(EDCs) and pharmaceuticals pose a challenge for water and wastewater treatment because they exist at very low concentrations in the presence of substances at much higher concentrations competing for adsorption sites.Sub-micron sized resin particles(approximately 300 nm in diameter)(SMR) were tested to evaluate their potential as a treatment for EDCs including:17-β estradiol(E2),17-α ethinylestradiol(EE2),estrone(E1),bisphenol A(BPA),and diethylstilbestrol(DES) as well as 12 pharmaceuticals.SMR were able to remove 98%of spiked E2,80%of EE2,87%of BPA,and up to 97%of DES from water.For a 0.5 ppm mixture of E2,EE2,E1,BPA and DES,the minimum removal was24%(E2) and the maximum was 49%(DES).They were also able to remove the pharmaceuticals from deionized water and wastewater.Overall,SMR are a promising advanced treatment for removal of both EDCs and pharmaceuticals.     

Levels of heavy metals in tissues of shingi fish (Heteropneustes fossilis) from Buriganga River, Bangladesh

Heavy metal pollution was reported in commercially valuable freshwater edible fish in the Buriganga River, Bangladesh. The concentrations of As, Pb, Cd, Cr, Zn, and Cu were investigated in the muscle, gill, stomach, intestine, and liver of Heteropneustes fossilis caught at three stations to assess the degree of fish pollution by heavy metals. Significant differences in concentrations of analyzed elements were observed among different tissues, but not among the stations. The ranges of the measured concentrations (μg/g dry weight) in the tissues of H. fossilis were as follows: arsenic concentration was (0.2–0.4), (0.82–0.90), (3.29–3.99), (2.20–2.80), and (2.41–2.90), that of lead was (1.79–2.20), (4.95–6.55), (10.36–13.38), (5.74–9.70), and (18.20–18.79), that of cadmium was (0.3–0.4), (2.87–4.27), (1.03–1.63), (1.55–4.59), and (2.25–5.50), that of chromium was (1.40–1.70), (3.52–3.72), (2.28–5.29), (2.77–3.79), and (4.25–8.65), that of zinc was (24.47–28.82), (16.82–18.80), (20.22–22.20), (22.86–26.68), and (60.82–67.80), and that of copper was (7.80–8.50), (6.22–6.81), (38.21–44.25), (17.07–21.03), and (43.24–47.30) in the muscle, gill, stomach, intestine, and liver, respectively. This research showed that the liver appeared to be the main heavy metal storage tissue, while the muscle had the lowest levels of analyzed metals. The concentrations of metal in the muscles not exceeded the acceptable levels for a food source for human consumption.     

Soil concentrations and source apportionment of polybrominated diphenyl ethers (PBDEs) and trace elements around a heavily industrialized area in Kocaeli,Turkey

Air pollutants are transported by dry deposition, wet deposition, and gas exchange accumulated in soil. Therefore, soil is an important environmental medium reflecting the level and the spatial distribution of air pollutants such as polybrominated diphenyl ethers (PBDEs) and heavy metals. Soil concentrations of seven PBDE congeners and 21 trace elements were determined in a heavily industrialized region (Dilovasi) in Kocaeli, Turkey. At all sites, Σ₇PBDE concentrations ranged from 0.70 to 203 with a mean value of 26.3 μg kg^?1 (dry weight). The congener profiles and mass inventories of PBDEs and their interactions with soil organic matter (SOM) were also investigated. BDE-209 was the dominant congener at all sites, followed by BDE-99 and/or -47. The estimated inventory of PBDEs for the Dilovasi district was 310 kg. However, there are several additional industrial regions in Kocaeli city. Considering the total land area, the potential inventory would be much larger for this city. The relationship between the PBDE concentrations in soil and SOM content indicated that factors other than soil properties have a greater influence on soil concentrations. Crustal enrichment factors (EFs) were determined; correlation analysis and factor analysis (FA) were also applied to generated data set to identify and apportion the sources polluting the soil. Sn, Mn, Ca, As, Zn, Pb, and Cd had significantly high average EF values, indicating that their soil concentrations were mainly influenced by anthropogenic activities. In FA, six factors were extracted with a cumulative variance of 84.4 % and industrial activities and traffic were found to be the main factors affecting the soil profile.     

Application of molecularly imprinted and non-imprinted polymers for removal of emerging contaminants in water and wastewater treatment: a review

Over the past decade, several studies have reported trace levels of endocrine disrupting compounds, pharmaceuticals, and personal care products in surface waters, drinking water, and wastewater effluents. There has also been an increased concern about the ecological and human health impact of these contaminants, and their removal from water and wastewater has become a priority. Traditional treatment processes are limited in their ability to remove emerging contaminants from water, and there is a need for new technologies that are effective and feasible. This paper presents a review on recent research results on molecularly imprinted (MIP) and non-imprinted (NIP) polymers and evaluates their potential as a treatment method for the removal of emerging contaminants from water and wastewater. It also discusses the relative benefits and limitations of using MIP or NIP for water and wastewater treatment. MIP, and in particular NIP, offer promising applications for wastewater treatment, but their toxicity and possible health effects should be carefully studied before they are considered for drinking water treatment. More research is also required to determine how best to incorporate MIP and NIP in treatment plants.