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Wastewater treatment plants receive influent wastewater that is contaminated with bacterial pathogens which may be released into the environment if the plant effluent is inadequately treated. In this study, next-generation sequencing was used to perform a 16S rDNA-based survey of bacterial populations in the influent and effluent from a treatment facility in the North-West Province (SA). In total, 3638 and 3872 effective DNA reads were obtained for the influent and effluent, respectively. Sequence analysis revealed the detection of a diverse bacterial constituency in both the influent and effluent samples. The phyla: Proteobacteria (49.82% and 52.04%), Firmicutes (14.06% and 13.14%) and Actinobacteria (5.00% and 9.99%) were found to be taxonomically abundant in the influent and effluent, respectively. This translated to the detection of biological treatment-, fecal coliform-, and disease-associated bacterial groups that are classified under the following genera: Escherichia spp., Serratia spp., Aeromonas spp., Legionella spp., Pseudomonas spp., Mycobacterium spp., Clostridium spp., Staphylococcus spp. and Streptococcus spp., Comamonas spp., Nitrosomonas spp., Acinetobacter spp., Rhodobacter spp., Paracoccus spp., Hyphomicrobium spp., and Desulfovibrio spp. [ABSTRACT FROM AUTHOR]

The declining state of municipal wastewater treatment is one of the major contributors to the many pollution challenges faced in most parts of South Africa. Escherichia coli and Chemical Oxygen Demand are used as indicators for the performance of wastewater treatment plants. Wastewater treatment plant (WWTP) efficiency challenges are associated with susceptibility to seasonal variations that alter microbial density in wastewater. This study sought to investigate the effect of rainfall on E. coli and COD in the effluent wastewater discharged from the Crocodile River, Mpumalanga Province, South Africa. To cover the spatial distribution of the pollutant in the Crocodile River, water samples were collected from 2016 to 2021 at three strategic sites. The rainfall data was acquired from the South African Weather Services from 2016 to 2021, which contains daily rainfall measurements for each sampling site. Data analysis was carried out using Microsoft Excel 2019, Seaborn package, and Python Spyder (version 3.8). The White River, which is located on the upper stream, recorded the highest COD levels of 97.941 mg/L and 120.588 mg/L in autumn and spring, respectively. Matsulu WWTP was found to have the highest E. coli concentration per milliliter (72.47 cfu/100 mL) in the spring compared to any other location or time of year. The results also indicated that each of the sampling sites recorded above 60 (cfu)/100 mL of E. coli in Kanyamazane (spring), Matsulu (summer), and White River (winter). It was noted that the rainfall is a significant predictor (p < 0.004) of E. coli. Additionally, it was discovered during the data analysis that the rainfall parameter did not significantly affect COD prediction (p > 0.634), implying that rain was not a reliable predictor of COD. [ABSTRACT FROM AUTHOR]

Excessive discharge of poorly treated effluent has impacted global water resource systems intensely. The declining state of wastewater treatment plants (WWTPs) is a significant source of pollution in water resources. There is evidence of water resource quality deterioration in natural environments caused by effluent discharges. We assessed the impact of wastewater treatment effluent on the quality of the Crocodile River. For spatial distribution, we collected data from three WWTPs discharging effluent into the Crocodile River and from three points situated downstream of each WWTP. Physicochemical and microbiological parameters such as pH, electrical conductivity, chemical oxygen demand, phosphates, nitrates, ammonia, and Escherichia coli were analysed using standard methods of the American Public Health Association. The water quality index was also calculated to give an overall indication of pollution within the catchment. The results show that WWTPs were not complying with the effluent standards set out in their water use licence. The WWTP effluent had a negative impact on downstream water quality, with the water quality index indicating low quality of discharged effluent. It is recommended that a regular and consistent water resource quality monitoring programme be implemented, particularly in areas where effluent discharges are prevalent. In many African nations, water pollution is a serious problem that may be traced to a variety of sources. Surface water pollution has adverse effects on aquatic ecosystems and reduces the availability of clean water. In most semi-arid to dry southern African regions (e.g. South Africa), water scarcity is a significant concern. In these regions, water is a vital resource that must be protected at all times, given that the inadequate infrastructure of wastewater treatment facilities adds to the decline in South Africa's water quality standards. [ABSTRACT FROM AUTHOR]

The Direct Estimation of Ecological Effect Potential (DEEEP) is a suite of toxicological methods that was compiled to facilitate management of effluent discharges. DEEEP used a range of tests to assess different endpoints and test taxa from differing trophic levels. It was used at pilot scale but never adopted in South Africa formally. The use of toxicological testing in managing effluent discharge has been somewhat ad-hoc since. This study examined a range of tests for undertaking toxicological assessments of effluent from the perspectives of ecological realism, test tractability, and cost of testing. The assays assessed include some from DEEEP, some using South African test taxa, and some using commercial toxicity test kits. Results indicate that, in terms of returned endpoints, no clear difference between tests using immobilized and cultured or wildcollected test taxa was present. Culture maintenance was found to be a significant contributor to test costs where cultured test taxa were used (although culture costs are implicit in test kit costs too). Costing analysis looked at scenarios where equipment could be shared and reused, and how these contribute to laboratory costs. The research leads on to suggestions for testing implementation in laboratories while maximizing ecological realism and minimizing costs. [ABSTRACT FROM AUTHOR]

Sappi Saiccor (situated in Durban, South Africa) dissolving pulp mill effluent, produced from an acid bisulphite pulping process, uses acacia and eucalyptus hardwoods to produce a unique and different blend of lignin that has not been previously studied. The chemical oxidation of lignin found in Sappi Saiccor's effluent has been investigated using a number of different chemical oxidising agents, such as nitrobenzene, oxygen with and without the presence of a copper sulphate pentahydrate catalyst, and hydrogen peroxide. The reaction products were extracted with acid and identified using GC-MS and LC-MS techniques. Nitrobenzene is a good oxidising agent but tends to produce many toxic by-products and would not be acceptable on an industrial scale. Oxygen oxidation has previously been shown to produce aldehyde-type compounds, and in this work has produced good yields of both vanillin and syringaldehyde compared to previous oxygen oxidation reactions. Hydrogen peroxide is a strong oxidising agent that tends to over-oxidise the lignin during long reaction times. [ABSTRACT FROM AUTHOR]

Winery effluent is known to have a high chemical oxygen demand (COD) and a low pH. In this study, we extensively analysed effluent from two cellars and studied the temporal changes over the duration of a harvest and the duration of a year. We found that ethanol contributes approximately 85% to 90% of the COD of raw winery effluent, with acetic acid being the next significant contributor. The pH showed some dependence on the concentration of acetic acid. The concentration of sodium in the effluent is strongly dependent on the cleaning regime in place at the cellar, and the concentration of potassium has been shown to be linked to the spillage of juice, wine or lees. The data and correlations presented here could allow for an artificial effluent to be prepared easily for research purposes. [ABSTRACT FROM AUTHOR]

The failure of South African wastewater treatment plants to produce effluents of a high microbiological quality is a matter of great concern in terms of the pollution of water resources. This study aimed at assessing the effectiveness of 4 wastewater treatment plants in the Gauteng Province, namely the Zeekoegat, Baviaanspoort, Rayton and Refilwe Water Care Works (WCW), in the removal of pathogenic bacteria and viral indicators. Also taken into consideration were free chlorine concentrations and turbidity levels, which were measured using standard methods. Conventional methods and/or polymerase chain reaction (PCR) techniques were used to detect and identify pathogenic bacteria and coliphages. The turbidity ranged from 2.39 to 62.40 NTU and the concentrations of free chlorine ranged from 0.03 tol.60 mg·ℓ-1 for all plants. Despite high free chlorine residual concentrations in treated effluents, the survival and occurrence of Escherichia coli, Salmonella typhimurium and Vibrio cholerae were significantly higher at Baviaanspoort (100%, 88.2% and 35.3%), Refilwe (87.5%, 59.4% and 2 1.9%) and Rayton (75%, 38.2% and 9.4%) compared to Zeekoegat, which only showed the survival of E. coli, at a much lower occurrence rate of 8.8%. Somatic and F-RNA coliphages were removed at 15.57% and 13.96% for Baviaanspoort, 11.62% and 22.42% for Refilwe, 25% and 32.10% for Rayton, and 40.41% and 52.57% for Zeekoegat WCW. Significant correlations were found between pathogenic bacteria and coliphages at all plants (r = 0.765 for Baviaanspoort, r = 0.904 for Zeekoegat, r = 0.680 for Refilwe, r = 0.796 or the Rayton WCW, p <0.01). A combination of sedimentation, rapid sand filtration and chlorination processes was found to be a major prerequisite for the reduction of turbidity levels and viral indicators and the successful removal of pathogenic bacteria in the Zeekoegat WCW. This study therefore suggests an upgrading of the wastwater treatment plants by including processes such as rapid sand filtration and UV disinfection, which have proved to be effective in the removal and inactivation of pathogenic bacteria and viruses. [ABSTRACT FROM AUTHOR]

The article presents a study that assesses the impact of a wastewater treatment facility's final effluent on the physicochemical properties of the watersheds in the Eastern Cape Province in South Africa. It states that the study used methodologies such as sampling method, physicochemical analyses, and data analyses. The study concludes that the discharged effluents have damaging effects on the water and suggests collaborating for appropriate standards for discharged effluents.

Mineral element uptake by the macrophytes Typha latifolia (bulrush) and Phragmites australis (common reed) from effluent (waste water) was investigated in a two-year sampling program carried out in constructed wetlands at a winery near Stellenbosch (33°55′S, 18°52′E), and at a distillery near Worcester (33°32′S, 19°13′E) in the Western Cape Province. Factors considered were: season of growth, site (distillery or winery), plant kind, wetland retention time and position in the wetland (inflow, outflow). Effluent nitrogen (N), potassium m (K), calcium (Ca), magnesium (Mg) and sodium (Na) concentrations were lower at the outflow than at the inflow at the winery, but not the distillery. Dry mass increases in both macrophytes were greater at the distillery than the winery. The distillery effluent contained higher concentrations of N and K than that from the winery. Tissue N, P, K, Na, Ca, Mg, copper (Cu) and zinc (Zn) concentrations were higher in plants at the distillery, than at the winery. Tissue N and K concentrations were, respectively, higher and lower in P. australis than in T. latifolia, Retention time, and position within the wetland, had either no, or inconsistent, effects on tissue element concentrations. The total element contents of the macrophytes were small in relation to the quantities of elements in the effluent. Where differences in effluent composition across the winery wetland were observed, these were probably due to biological activity in the effluent itself, on the limestone gravel surfaces, or on the plant roots. [ABSTRACT FROM AUTHOR]

Objectives: The resistome, virulome, mobilome and phylogenetic relationship of the Acinetobacter baumannii isolate FG121 depicting the multilocus sequence type (ST) 231 isolated from hospital effluent water in South Africa was determined using whole-genome sequence analysis., Method: A. baumannii FG121 was isolated on Leed Acinetobacter Medium (LAM) agar and the bacterial isolate was identified using the VITEK®2 platform. Antibiotic susceptibility testing was performed using Kirby-Bauer Disk diffusion method. A whole genome sequencing library was constructed from DNA extracted from the isolate using the Illumina Nextera XT library preparation kit and was sequenced using the Illumina NextSeq500 platform. Generated reads were de novo assembled using SpAdes v.3.9. The assembled contigs were annotated, and multilocus sequence type, antimicrobial resistance, and virulence genes were identified., Results: The resistome was consistent with the resistance phenotype of the isolate with resistance determinants for beta-lactams, aminoglycosides, and tetracycline (bla ADC-25 , bla OXA-23 , bla OXA-51 , bla NDM-1 , aph[3']-VIa and tet[B]). Global phylogenomic analysis using BacWGSTdb revealed that the isolate belonged to the multilocus sequence type ST-231, similar to previously reported isolates from South Africa, the United States, and related to the invasive KR3831 isolate identified from Oman in 2012, suggesting the isolate might be imported from abroad. Virulome analysis predicted both virulence and biofilm-determinants of A. baumannii, which may help to establish infections in adverse conditions., Conclusion: This is the first report on a carbapenemase-encoding A. baumannii ST-231 isolated from hospital effluent water. Our data will offer insight into the global phylogenetic, pathogenicity and distribution of A. baumannii in South Africa., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Compliance of the effluents from wastewater treatment plants (WWTPs) to the regulatory standards, which mostly entail the removal/reduction of organic waste and deactivation of the potential microbial pathogens is of great importance. The detection of indicator parameters can be used to determine the effectiveness of a WWTP and the level of compliance with the South African regulatory standards. The performance of the WWTP was assessed by biological, physical and chemical measures in wastewater final effluent. The Escherichia coli ranged from 0 and 2420 count/100 mL in the final effluent. The recorded values for the physicochemical parameters were within the following ranges: pH (7.03-8.49), electrical conductivity (81.63-126.5 mS/m), suspended solids (0.40-20.4 mg/L), ammonia (0-22.15 mg/L), Chemical Oxygen Demand (COD) (1-73 mg/L), nitrate (0-16.1 mg/L), ortho-phosphate (0-8.58 mg/L) and free chlorine (0-3.21 mg/L). Furthermore, the concentration of toxic heavy metals was recorded to be between 1-10 ug/L for arsenic, cadmium, lead and mercury. In conclusion, all the parameters that were evaluated in this study indicate that the studied WWTP is performing in accordance with the prescribed general limits.

Monitoring effluents from wastewater treatment plants is important to preventing both environmental contamination and the spread of disease. We evaluated the occurrence of human enteric bacteria (faecal coliforms and Escherichia coli) and viruses (rotavirus and enterovirus) in the final effluents of five wastewater treatment plants (WWTPs) in the Eastern Cape of South Africa. Human viruses were recovered from the effluent samples with the adsorption-elution method and detected with singleplex real-time RT-PCR assays. Rotavirus was detected in several effluents samples, but no enterovirus was detected. At WWTP-C, rotavirus titre up to 10 5 genome copies/L was observed and present in 41.7% of the samples. At WWTP-B, the virus was detected in 41.7% of samples, with viral titres up to 10 3 genome copies/L. The virus was detected once at WWTP-E, in 9% of the samples analysed. The viral titres at WWTP-A were below the detection limit in all 25% of the 1.25L samples in which the virus was detected. Rotavirus was not observed at WWTP-D. Faecal coliform bacteria and E. coli were detected in all the WWTPs, but no correlation was established between the enteric bacteria and viruses studied. The occurrence of rotavirus in effluent samples discharged into surface waters highlights the importance of assessing viral contamination in the water sources used for domestic water use., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

South Africa is a water scarce country with an average annual rainfall of less than 60% of the world average. It is therefore important to encourage industries to minimise water consumption, and recycle andre-use water and effluent where possible. The South African Department of Water Affairs and Forestry is responsible for the management ofwater resources in South Africa, thereby ensuring the provision of adequate water supplies of acceptable quality for all recognised users. Of the industrial effluents produced in South Africa, textile effluents are considered to be one of the most problematic in the KwaZulu-Natal coastal area, especially in terms of colour, chemical oxygen demand (COD) and salinity (total dissolved solids, TDS). Of these, colour is perceived to be the most problematic as it is visual pollution and gives rise to public complaints. The Department has been activelyinvolved, through negotiations with management and local authorities, in encouraging the textile industries to reduce the colour load discharged from the factories. Four case studies will be presented describing the approach taken by the Department to solve the problem of textile effluent discharge. [ABSTRACT FROM AUTHOR]