Journal of water and health最新文献

Different species of free-living amoeba (FLA) have been abundantly isolated in harsh environmental conditions such as hot springs and brackish water. The present study aimed to isolate, genotype, and evaluate the pathogenicity of FLAs in Qom Roud, a large river, in the centre of Iran. About 500 mL of water samples (n = 30) were collected from each sampling site and were investigated for the presence of FLAs using morphological and molecular characters. Genotype identification was performed using DNA sequencing and a phylogenetic tree was constructed with the MEGA X software. The pathogenic potential of all positive isolates was evaluated using the tolerance ability test. Morphological and molecular analysis indicated that 14 (46.66%) and two (6.66%) water samples were positive for Acanthamoeba species and Vahlkampfiidae, respectively. According to sequence analysis, Acanthamoeba isolates related to the T4 genotype and Vahlkampfiidae sequences were similar to Naegleria philippinensis. In the next step, thermo- and osmotolerance tests indicated four Acanthamoeba strains are extremely pathogenic. Our data showed the presence of potentially pathogenic Acanthamoeba T4 genotype and N. philippinensis in the super harsh Qom Roud. Contamination of water with virulent T4 genotype of Acanthamoeba may pose risk factors for contact lens users, children, and immunocompromised people.

The establishment of national strategic frameworks for systematic scaling-up of water safety plans (WSPs) implementation needs to overcome major constraints: lack of legislation and policies, and the need for appropriate monitoring tools. In 2018, the Uruguayan regulator for energy and water services promulgated a regulation intended to ensure an ambitious and pragmatic strategy that supports and promotes WSP implementation and auditing at a national scale. The goal is to have all drinking water supply systems with their WSP implemented by 2030. For this, a demanding schedule was recommended considering the size of the drinking water supplies: (i) large systems serving more than 2,000 inhabitants and (ii) small and very small systems serving fewer than 2,000 inhabitants. A mandatory verification through internal and external audits was also established. This work describes the legal and regulatory framework as well as the challenges and opportunities that open up for the generalization of WSP implementation in Uruguay. Despite the impact of COVID-19 on working conditions for water suppliers, as for the year 2022, WSPs have been successfully implemented in 94 water systems serving more than 2.4 million people. Results of successful implementation and auditing processes are presented and discussed covering methods and outcomes.

The study aims to understand the relationship of childhood diarrhoea (under-five children) with water, sanitation and hygiene factors in the light of other contextual factors in an urban setting in the district of Hooghly in West Bengal, India. This primary study was carried out by SIGMA Foundation, Kolkata from 4 to 24 January 2023 across 404 households having at least one under-five child. The findings suggested that the water score was 'good' in 85.1% of the households whereas the hand hygiene score was 'good' in 14.6% of households. More than 90% of the households had piped water supply. Less than half of them treated water before consumption among which 45.3% used cloths for straining water; 59.2% of the caregivers followed safe disposal of child's faeces; 66.8% of households had no handwashing arrangement, and 30.5% had taps and wash basins for handwashing; 20.3% of the under-five children had suffered from diarrhoea in the last month before the survey and its prevalence was higher in children aged 12-23 months. Multivariate results suggested diarrhoea prevalence was lower in households that were pucca and had good water and hand hygiene scores, lower in children that had received iron fortification and whose caregivers followed safe child's stool disposal.

In Nigeria, artisanal mining has become a serious issue. In the Nigerian mining region of Arufu Pb-Zn-F, this study assessed the level of pollution, ecological hazards, and health risks related to the presence of metals in the water. In the dry and rainy seasons, 36 water samples (20 from the ground, 10 from the surface, and six from the mine) were gathered. Samples were examined for the presence of heavy metals such as Cr, Co, Ni, Cu, Zn, As, Cd, and Pb. Other than Cu, Zn, As, Cd, Sb, and Cd (surface water, dry season), which were below the acceptable norm, all water samples had metals over the suggested limits. Heavy metals from nearby mining activities polluted the water, according to contamination evaluations utilizing the contamination factor (CF). Metals in the water may pose very significant ecological dangers, according to ecological risk assessments. The evaluation of human health risks revealed that both adults and children in the region are susceptible to carcinogenic and non-carcinogenic health hazards since the hazard index (HI) values for both indices were above 1 × 10^-5 and above 1, respectively. This report emphasizes the need for monitoring mining operations in the nation to safeguard public health.

The specific contributions of the different bacterial flora during the biological treatment of slaughterhouse effluents remain unclear. The objective of this study is to identify the different microbial flora which mainly contribute to the efficiency of the biodegradation of the organic, nitrogenous and phosphate loads contained in the slaughterhouse effluent during its biological treatment. To achieve this, the effluent to be treated was sampled from three slaughterhouses in the city of Ngaoundéré (Cameroon). The various effluents underwent a physicochemical and microbiological characterization. The effluent was subjected to biological treatment. The biodegradation process (biological treatment) took place in two reactors, each operating in batch. One of the two reactors was supplied with oxygen (aeration). The effluent being treated underwent a physicochemical and microbiological characterization for 30 days. The results obtained show organic matter and ammonium contents >1,000 mgO₂/L in each of the three effluents. Bacillus cereus (69 × 108 CFU/mL), Pseudomonas aeruginosa (201 × 107 colony forming unit (CFU)/mL) and Yeasts (101 × 106 CFU/mL) globally constitute the majority of microbial groups among the seven microorganisms identified in the effluents of the three slaughterhouses. There is no real oxygenation effect of the medium on the growth of the three microbial flora during the treatment.

The water treatment system for hemodialysis (HD) is used to treat multiple patients requiring HD simultaneously. This system requires a large amount of purified reverse osmosis (RO) water. However, a major drawback of this method is the formation of biofilms in dialysate pathways. The purpose of this study was to investigate the efficacy of NOC 18, a nitric oxide (NO) donor that can be used at neutral pH, in disinfecting the RO water pathway. Silicone tubes were obtained from the terminal sites of two different HD units. The biofilm coverage and mean biofilm thickness on the tube lumen were evaluated by scanning electron microscopy. The results demonstrated that treatment with NOC 18 alone and in conjunction with sodium hypochlorite reduced biofilm coverage and mean biofilm thickness. Thus, NO donor is a potential disinfectant that enhances bacterial dispersion from biofilms formed on the silicone tube lumen and reduces biofilm coverage and thickness on the RO water pathway at neutral pH. Furthermore, combined disinfection with the NO donor and sodium hypochlorite might enhance biofilmremoval efficacy in clinical practice.