Combining physicochemical properties and microbiome data to evaluate the water quality of South African drinking water production plants

Abstract

Anthropogenic activities in catchments used for drinking water production largely contaminates source waters, and this may impact the quality of the final drinking water product. These contaminants may also affect taxonomic and functional profiles of the bacterial communities in the drinking water. Here, we report an integrated insight into the microbiome and water quality of four water treatment plants (NWC, NWE, WCA and NWG) that supply portable water to communities in South Africa. A new scoring system based on combined significant changes of physicochemical parameters and microbial abundance from raw to treated water was used to evaluate the effectiveness of the treatment plants at water purification. Physicochemical parameters which include total soluble solids, turbidity, pH, nitrites and phosphorus among others, were measured in source, treated, and distributed water. There were general statistically significant (P � 0.05) differences between raw and treated water, demonstrating the effectiveness of the purification process. Illumina sequencing of the 16S rRNA gene was used for taxonomic profiling of the microbial communities and this data was used to infer functional attributes of the communities. Structure and composition of the bacterial communities differed significantly (P < 0.05) among the treatment plants, only NWE and NWG showed no significant differences (P > 0.05), this correlated with the predicted functional profile of the microbial communities obtained from Phylogenetic Investigation of Communities by Reconstruction of Observed States (PICRUSt), as well as the likely pollutants of source water. Bacteroidetes, Chlorobi and Fibrobacteres significantly differed (P < 0.05) between raw and distributed water. PICRUSt inferred a number of pathways involved in the degradation of xenobiotics such as Dichlorodiphenyltrichloroethane, atrazine and polycyclic aromatic hydrocarbons. More worryingly, was the presence of pathways involved in beta-lactam resistance, potential pathogenic Escherichia coli infection, Vibrio cholerae infection, and Shigellosis. Also present in drinking and treated water were OTUs associated with a number of opportunistic pathogens.

Metagenomic analysis of bacterial communities of Wadi Namar Lake, Riyadh, Saudi Arabia

“…Cl and total N were measured using a colorimetric method flowing digestion ( Fournier et al, 2021 ). The total dissolved solids were measured by a multi- 350 probe analyser (Merck, Darmstadt, Germany) according to a method described elsewhere ( Maguvu et al, 2020 ).…”

“…For making metagenomic investigation more available through targeted metagenomics, the Next Generation Sequencing (NGS) has been considered ( Amrane and Lagier, 2018 ). Lake microbiome links to many water characteristics, such as temperature, pH and nutrient concentration as well as anthropogenetic actions ( Maguvu et al, 2020 ). In the present study, 16S metagenomic analysis was used to investigate the bacterial community of Wadi Namar Lake - a new tourist attraction area located in the Riyadh region, Saudi Arabia, as common picnic spot, around which pollution by municipal wastes was noticed.…”

Inferring microbiota functions from taxonomic genes: a review

“…Some interesting examples exist in the biomonitoring and bioassessment of water quality [ 153 , 154 ], but examples for the soil microbial quality are still scarce. The huge complexity and diversity of the soil microbial community probably still limits such applications to the soil ecosystem, along with a lack of genome references.…”

A Multivariate Model of Drinking Water Quality Based on Regular Monitoring of Radioactivity and Chemical Composition

“…Nitrates and nitrites, often associated with anthropogenic activities, are volved in the maintenance and development of microorganisms which can influence w ter turbidity [89,90]. Thus, new methods for a combined evaluation of physical-chemi parameters and microbiome data have been developed [91]. The national report highlights Mn, Fe, ammonia, and nitrates as the main chemical parameters exceeding the allowed values for some chemicals, from 15% for Mn to 7.8% for nitrates, of all samples collected in 2021 from small supply zones all over the country [73].…”

“…Nitrates and nitrites, often associated with anthropogenic activities, are involved in the maintenance and development of microorganisms which can influence water turbidity [89,90]. Thus, new methods for a combined evaluation of physical-chemical parameters and microbiome data have been developed [91].…”