The present study was aimed to analyze the influence of industrial and agricultural wastes on quality ofKosi river water, Rampur, UP, India. The results of the present study revealed pH values of between 7.2 and 6.3 (neutral to slightly acidic), the electrical conductivity between 129.4 μs/cmto399.3 μs/cm. The maximum EC value was observed at S5 in spring season. The turbidity of each was 0.4 to 7.067 NTU. The highest turbidity observed at S5 in winters. Total hardness of 73 (mg/L) and 506.33 (mg/L) were evident at S4 and S7 sites respectively. The BOD values ranged from 10.5 (mg/L) at S4 to 137.4 (mg/L) at S5. Higher BOD values at each site are reflecting the great extent of pollution. The minimum COD recorded at S3 (32.60 mg/L) however maximum recorded at S5 (168.65 mg/L). The results of the heavy metals showed a significant increase in the concentration of Pb, Zn, Cu, Hg and As at S5 as compared to the other sites. The As concentration was 0.04, 0.08, 0.85, 0.72 and 0.71 at S2, S3, S5, S6, and S7 respectively. These values were higher than the value of Arsenic as per WHO guidelines.The average concentration of Zn obtained was 0.05, 0.786, 0.413, 0.06, 3.26,0.97 and 0.53 mg/L at S1, S2, S3, S4, S5, S6, and S7 respectively. The highest value of Zn was recorded at S5 (SDP) as compared to other sites. Only at S5 the zinc content is exceeding the normal value. The copper content found to be lower (1.0 mg/Ll) than permissible value according to WHO. The Cu concentration was 0.01, 0.06 0.01 at S4, S5 and S6 respectively, at S1,S2, S3 and S7 zero. The changed physicochemical parameters and occurrence of heavy metal ions indicated a significant level of pollution in Kosi River.

Populations at large are exposed towards Arsenic (As) contamination in water worldwide making it unfit for drinking and human consumption. This study was designed to assess As removal efficiency of newly developed thiolated chitosan cobalt-doped zinc oxide (CoZnO) nanoparticles (NP) under visible light spectrum. In this study the Co-ZnO NP of various sizes (40–60 nm) were prepared through the co-precipitation method. Removal of As with Co-ZnO NP was investigated in batch tests experiments alongside determining the optimal dose of NP, kinetic rates, effect of light, pH and ultra-sonication. This was followed by a continuous flow test with Co-ZnO layered on Whatman® grade 42 filter paper. Overall, the Co-ZnO NP effectively treated As i.e. in sunlight (100%), neutral pH (100%), ultra-sonication (100%) and in continuous-flow system (100%). The removal of As was maximum (88%) at NP:As ratio of < 1:5 and minimum (25%) at 1:100. Similarly, darkness (21.4%) and (11.1%) uptake at low and high pH respectively. It was found that Co-ZnO NP can efficiently reduce As to non-toxic state i.e. below the WHO permissible limit of (10 µg/L) in drinking water.