RESUMEN
A comprehensive understanding of water quality is essential for assessing the complex relationship between surface water and sources of pollution. Primarily, surface water pollution is linked to human and animal waste discharges. This study aimed to investigate the physico-chemical characteristics of drinking water under both dry and wet conditions, assess the extent of bacterial contamination in samples collected from various locations in District Shangla, and evaluate potential health risks associated with consuming contaminated water within local communities. For this purpose, 120 groundwater and surface water samples were randomly collected from various sources such as storage tanks, user sites, streams, ponds and rivers in the study area. The results revealed that in Bisham, lakes had the highest fecal coliform levels among seven tested sources, followed by protected wells, reservoirs, downstream sources, springs, rivers, and ditches; while in Alpuri, nearly 80% of samples from five sources contained fecal coliform bacteria. Similarly, it was observed that the turbidity level, total dissolved solids, electrical conductivity, biological oxygen demand, and dissolved oxygen in the surface drinking water sources of Bisham were significantly higher than those in the surface drinking water sources of Alpuri. Furthermore, the results showed that in the Alpuri region, 14% of the population suffers from dysentery, 27% from diarrhea, 22% from cholera, 13% from hepatitis A, and 16% and 8% from typhoid and kidney problems, respectively, while in the Bisham area, 24% of residents are affected by diarrhea, 17% by cholera and typhoid, 15% by hepatitis A, 14% by dysentery, and 13% by kidney problems. These findings underscore the urgent need for improved water quality management practices and public health interventions to mitigate the risks associated with contaminated drinking water. It is recommended to implement regular water quality monitoring programs, enhance sanitation infrastructure, and raise awareness among local communities about the importance of safe drinking water practices to safeguard public health.
Asunto(s)
Agua Potable , Microbiología del Agua , Calidad del Agua , Pakistán , Agua Potable/microbiología , Agua Potable/química , Humanos , Monitoreo del Ambiente/métodos , Agua Subterránea/microbiología , Agua Subterránea/química , Heces/microbiología , Bacterias/aislamiento & purificaciónRESUMEN
Granulation of halophilic activated sludge is an important solution to solve the problem of solid-liquid separation in biological treatment of saline wastewater. This study demonstrated that by adding divalent cations into the saline influent with low organic load, halophilic granular sludge with an average diameter of 910 ± 10 µm can be cultivated. The close correlation between divalent cations and particle size indicated that Ca2+ played a major role in the granulation process. Ca2+ was accumulated in halophilic granular sludge, which provided an inorganic carrier for microbial aggregation and leaded to the dominance of halophilic bacteria of the family Flavobacteriaceae. The halophilic bacteria secreted a large amount of extracellular polymeric substances (EPS), which contained 70.0 ± 0.02% protein. By enhancing the EPS network of protein and Ca2+, halophilic granular sludge was formed. The addition of Mg2+ enhanced the network of Mg2+ and loosely bound EPS, which could be destroyed due to Na+ substitution. This study provides an effective granulation method for halophilic activated sludge.
Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Reactores Biológicos , Cationes Bivalentes , Matriz Extracelular de Sustancias Poliméricas , Eliminación de Residuos LíquidosRESUMEN
As a solution of the sludge loss in the treatment of saline wastewater, the granulation of halophilic sludge was explored in this study. The inoculated estuarine sediment was granulated to an average diameter of 1155⯱â¯102⯵m under the selective settling pressure in the airlift sequencing batch reactor (SBR) when the influent organic loading rate (OLR) was doubled to 0.36â¯g COD/L·day. The results indicated that the OLR doubled the amount of total extracellular polymeric substance (EPS) and that protein was predominant in the EPS (72.8⯱â¯2.0%). The correlation between aggregate size and protein content was better than that between aggregate size and polysaccharide content. The amount of alginate-like exopolysaccharides (ALE) increased linearly at the mature granular stage, co-occurring with the compact and elastic structure of the granules. According to the results of 16S rRNA high -throughput sequencing, the Shannon-Weaver index of mature granule decreased by >50% compared to the inoculated sediment. Bacteria of Propionibacteriaceae family constituted 34% of the population in granules and were in symbiotic relationship with halophiles of family Rhodocyclaceae, Vibrionaceae, Flavobacteriaceae, and Cryomorphaceae. The aerobic halophilic granular sludge showed COD removal efficiency of 90.9⯱â¯0.8% and ammonia removal efficiency of 72.6⯱â¯4.0% for 30â¯g/L saline wastewater. An average nitrite accumulation ratio of 94.5⯱â¯2.9% was observed during nitrification. Granulation of halophilic sludge provides an effective solution to the saline sludge loss problem, which is a step forward to realize the biological treatment of saline wastewater by halophiles.