Water conservation due to greywater treatment and reuse in urban setting with specific context to developing countries

In India, the per capita water availability is reducing day by day due to rapid growth in population and increasing water demand. Greywater treatment and reuse is one of the feasible options in developing countries like India to overcome this problem. A greywater collection, treatment and reuse system was designed and implemented in an urban household having a water requirement of 165 liter per capita per day (lpcd) and a greywater generation rate of 80 lpcd. An upflow-downflow greywater treatment plant having a screening, sedimentation, filtration and disinfection as major treatment processes was constructed and treated greywater is used for toilet flushing and to irrigate the vegetables in the backyard of the household. Greywater characterisation indicates that COD and BOD are sufficiently reduced during the treatment and there is also substantially reduction in Escherichia coli count. The payback period of this greywater treatment and reuse system is estimated to be 1.6 year.     

Evaluation of Extracted Chitosan from Portunus Pelagicus for the Preparation of Chitosan Alginate Blend Scaffolds

In recent years there is a growing need in generating a biocompatible and cost effective porous scaffold for tissue engineering purposes. Therefore, this study focused on conversion of the shell waste of locally available crab variety P.pelagicus (Blue swimming crab) into the chitosan scaffold. As the poor mechanical strength of chitosan limits its usage in tissue engineering, it was blended with alginate. The scaffolds were prepared by the freeze gelation method which requires less time and minimum energy, with fewer residual solvent and easier to scale up. To the best of our knowledge there are no reports on scaffold preparation from the extracted chitosan, blended with alginate by freeze gelation method. The biological properties of chitosan-alginate scaffolds (Cts–Alg) were evaluated and compared with those of chitosan scaffolds. The prepared scaffolds were characterized by SEM, swelling property, in vitro enzymatic degradation, and hemo, biocompatibility properties. Chitosan-alginate scaffolds had an average pore size of 40 μm and tensile strength of 0.564 ± 0.0.018 % MPa. Its swelling ratio was 27.5 ± 0.28 %, with mass loss percentage of 10 ± 0.33 % after 4 weeks of degradation. It has exhibited good hemocompatible properties too. Mouse fibroblast 3T3 cells were able to adhere and proliferate well in the blended scaffold. All these results indicated that chitosan-alginate scaffold is a suitable alternative substitute for tissue engineering.     

Simultaneous sampling of gas- and aerosol-phase TDI with a triple filter system

A new triple filter system sampler/model is proposed for the precise and accurate simultaneous sampling and determination of gas- and aerosol-phase 2,4-toluene diisocyanate (TDI). The system consists of two front Teflon filters for sampling aerosol-phase TDI and a final coated glass fiber filter to collect gas-phase TDI. The aerosol-phase TDI is collected on the first Teflon filter, while the second Teflon filter is used to estimate gaseous TDI adsorbed by the first. According to the gas adsorption test of two Teflon filters in series, the TDI gas adsorption fraction of the two filters is almost the same. Results of the evaporation test using pure TDI aerosols collected on the Teflon filter show that significant evaporation of the compound does not occur during sampling. These two findings allow the use of a model to estimate accurate gas- and aerosol-phase TDI concentrations. The comparison test with an annular denuder shows that the triple filter system can minimize the TDI sampling bias between the dual filter and the annular denuder systems.     

Impact of industrialization on groundwater quality – a case study of Peenya industrial area, Bangalore, India

The present study aims at identifying the groundwater contamination problems in Bangalore city in India. Groundwater samples from 30 different locations of the industrial area were collected. Analytical techniques as described in the Standard methods for the examination of water and wastewater were adopted for physico-chemical analysis of these samples and the results compared with the Bureau of Indian Standards (BIS) guideline values for potable water in the light of possible health hazards. The investigations reveal that most of the study area is highly contaminated due to the excessive concentrations of one or more water quality parameters such as Nitrates, Total Hardness, Calcium, Magnesium, Total dissolved solids, Sulphates and Fluorides, which have rendered nearly 77% of the water samples tested, non- potable. Discussions held by the authors with the local public as well as the Primary health centre authorities of the area revealed that a lot of people in the area are suffering from severe health problems on using this water. The findings show that there is a clear correlation between the ill health faced by the public and contamination of the said groundwaters.     

Diversity of phytoplanktons in a waste stabilization pond at Shimoga Town, Karnataka State, India

To understand the diversity of phytoplanktons in waste stabilization pond effluents the hitherto study is undertaken. Species diversity indices of Shannon-Wiener and Simpson were applied to phytoplanktons. The diversity indices are of mathematical function to explain the abundance of each species. The total numbers of algae identified were 71 species belonging to Cyanophyceae, Chlorophyceae, Euglenophyceae, Bacillariophyceace and Desmidaceae. Chlorella and Scenedesmus were the dominant forms among the algal genera throughout the study period. Phytoplanktons play a vital role in improving the water quality of wastewater in waste stabilization ponds. Diversity indices provide important information about rarity and commonness of species in a community. The diversity indices of all the species explained the water was moderately polluted with less diversity level and highest possible equal number of different species of phytoplanktons. Greater impact of pollution leads to the lesser diversity of phytoplanktons.     

Effect of cortisol on female freshwater fish Notopterus notopterus

In the present study, effect of cortisol on the ovary of the freshwater fish Notopterus notopterus was studied during four phases of the reproductive cycle. The hormone was injected 60microg/fish for ten days. Cortisol in fish is known to increase the metabolic activity. After the hormone treatment the ovarian somatic index and the hepatosomatic index increases during non breeding phase. The young oocytes transferred into vitellogenic oocytes in all the phases after cortisol treatment. The cortisol induced increased ovarian activity may be due to increase in the metabolic activity through the involvement of hepatic cells specially during non-breeding period providing support for energy production for reproductive activity in the freshwater fish N. notopterus.     

Performance enhancement of solar photovoltaic system for roof top garden

Environmental Science and Pollution Research - The photovoltaic (PV) for irrigation system is an emerging technology to harness the solar energy. The performance of the PV modules depends on the...     

Effect of Zn salts and hydrolyzing agents on the morphology and antibacterial activity of zinc oxide nanoparticles

Environmental Chemistry Letters - Zinc oxide nanoparticles (ZnONPs) are considered safe as antibacterials. Those nanoparticles should preferably have uniform size and shape, but conditions to...     

Evaluation of vibrant muscles over the shoulder region among workers of the hand screen printing industry

This study focuses on evaluation of the muscle activities associated with shoulder pain among workers of the hand screen printing (HSP) industry. Activities of three major muscles which showed higher muscle activity for a HSP job were observed for fatigue using surface electromyography (SEMG). The anatomical sites were chosen on the basis of a statistical survey and a visual inspection conducted before the experiment. Activities of the deltoid, teres major and infraspinatus were recorded using SEMG and the nature of muscle activities was studied for about 50?m of cloth printing. Data collected were processed using LabVIEW 2014 and the activities were analyzed using statistical tests and regression analyses. The results showed an increased risk of shoulder disorders with an increase in working time. Some of the risks which might cause disorders were predicted from the results; inspection and possible mitigations were suggested.     

Soil and plant selenium at a reclaimed uranium mine

Selenium (Se) associated with reclaimed uranium (U) mine lands may result in increased food chain transfer and water contamination. To assess post-reclamation bioavailability of Se at a U mine site in southeastern Wyoming, we studied soil Se distribution, dissolution, speciation, and sorption characteristics and plant Se accumulation. Phosphate-extractable soil Se exceeded the critical limit of 0.5 mg/kg in all the samples, whereas total soil Se ranged from a low (0.6 mg/kg) to an extremely high (26 mg/kg) value. Selenite was the dominant species in phosphate and ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extracts, whereas selenate was the major Se species in hot water extracts. Extractable soil Se concentrations were in the order of KH2PO4 > AB-DTPA > hot water > saturated paste. The soils were undersaturated with respect to various Se solid phases, albeit with high levels of extractable Se surpassing the critical limit. Calcium and Mg minerals were the potential primary solids controlling Se dissolution, with dissolved organic carbon in the equilibrium solutions resulting in enhanced Se availability. Adsorption was a significant (r2 = 0.76-0.99 at P < 0.05) mechanism governing Se availability and was best described by the initial mass isotherm model, which predicted a maximum reserve Se pool corresponding to 87% of the phosphate-extractable Se concentrations. Grasses, forbs, and shrubs accumulated 11 to 1800 mg Se/kg dry weight. While elevated levels of bioavailable Se may be potentially toxic, the plants accumulating high Se may be used for phytoremediation, or the palatable forage species may be used as animal feed supplements in Se-deficient areas.