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Wastewater from textile industry is considered one of the major environmental challenges due to the large volume of highly colored, polluted and toxic effluent. This study investigated the treatability of real textile wastewater by pilot-scale anoxic-aerobic Membrane Bioreactor (MBR) system without sludge wasting for operation period of 100 days. The proposed system was investigated under different Internal Recycle (IR) ratios and the impact of IR ratio on Total Organic Carbon (TOC), Total Nitrogen (TN) and Color removals were examined. Under IR ratios between anoxic and aerobic tanks of 0.0, 0.5 and 2.0, the respective average removal efficiency of TN was 20.9%,53.4% and 71.7%, whereas average color removal of 81%, 85% and 88%, respectively was noted. The results indicated that increase of recycle ratio from 0.5 to 2.0 enhanced TN removal to about 71% and color removal to above 85%. The IR between anoxic and aerobic tanks has a significant role in TN and color removal due its effect on the development of bacterial communities. On the other hand, the results indicate over 93% TOC removal, which was independent of IR ratio.

Dimethoate is an organophosphate (OP) insecticide used in agriculture to kill insects. However, information on the effect of the insecticide on non-target organisms like phytoplankton is sparse. When dimethoate enters water ecosystems, it affects the photosynthesis of the phytoplankton cells. The effect of dimethoate on the photosynthesis mechanism of three Chlorophyceaen and two Bacillariophyceaen species was studied measuring oxygen production, chlorophyll fluorescence and xanthophyll pigments. Oxygen evolution rates of the five phytoplankton species decreased with increasing dimethoate concentrations. OJIP fluorescence characteristics in presence of dimethoate was similar to those of DCMU inhibition. DCMU is a PSII inhibitor used as a positive control. Non-photochemical quenching (NPQ) development and the concentration of specific xanthophyll pigments decreased with increasing insecticide concentration, giving another evidence for the target of dimethoate in the selected phytoplankton species. Dark relaxation kinetics did not show a photoinhibition of the cells in presence of dimethoate. Perfekthion, the commercial formulation of dimethoate, inhibited the photosynthesis of the tested phytoplankton species stronger than dimethoate, leading probably to photoinhibition.

In the current study, three different photo-assisted sources were used to evaluate the photo-Fenton oxidation process for the pollutant degradation of mature landfill leachate. Solar, UV, and LED visible light photo sources were adopted in this Fenton process. Fenton dosages (FeSO4 : H2O2) 1:30, 1.5:30, 2:30, and 2.5:30g/L were used in the investigation, which was conducted under a variety of pH settings (2 to 3.5) and at experimental reaction duration of 30, 60, 90, and 120 minutes. To analyze and compare the efficiency of the solar, UV, and LED visible light photo Fenton processes for pollutant degradation, Taguchi experimental design orthogonal arrays (L16) was employed. To analyse the significance of this experimental design for landfill leachate treatment, Larger the Better was selected. The highest levels of pollutant degradation in the Solar Photo Fenton method was identified when compared to UV, and LED visible light photo Fenton processes. The maximum removal of 95% color, 83% COD, 89% TSS, 94% Cr, 86% Cd, and 93% Cu was achieved in Solar Photo Fenton process at pH-3, Fenton dosage 1.5:30 g/L and reaction period 60 minutes.

To assess the indoor air quality an investigation was conducted in Lucknow from November 2014 to October 2015. In total seven pollutants viz. SO2, NO2, CO2, CO, NH3, H2S, PM10 and PM2.5 were assessed in five urban and five rural houses. House selection was done after questionnaire survey with respiratory patients in two medical colleges. The average concentrations of PM10 (280 and 315 µg m-3) and PM2.5 (185 and 210 µg m-3) were highest in winter season. Excessive consumption of crude fuel to combat cold conditions was associated with high particulate concentrations in rural houses. Smoking was a common habit recognized indoors. Skin irritation was common during rainy season whereas complaints of cataract, cough and sneezing were prevalent in winters. Air quality index was calculated using three different methods and was poorest in winter season in rural houses particularly with values 716.1, 457.0 and 7.427 as calculated.