Mycological and Physicochemical Assessment of Drinking Water from Pupils' Bottles

This study investigated the microbial and physicochemical properties of drinking water samples collected from pupils’ water bottles, with a focus on fungal contamination. Water samples were collected aseptically and analysed using standard microbiological and physicochemical methods. Fungi were isolated by serial dilution and cultured on Potato Dextrose Agar, followed by incubation. Morphological and cultural characteristics were examined, and microscopic identification was conducted using lactophenol cotton blue staining. Molecular identification was carried out via PCR amplification targeting the 18S rRNA gene, and amplified products were analysed by gel electrophoresis. The mean microbial load of fungal isolates ranged from 1.04×10⁴ to 2.56×10⁴ sfu/mL, exceeding the WHO permissible limit of 1.0×10² CFU/mL. Identified fungal species included Aspergillus niger, Fusarium poae, and Penicillium chrysogenum, with A. niger and F. poae each accounting for 40% occurrence, and P. chrysogenum 20%. Physicochemical analysis showed that most parameters were within WHO and FEPA limits, except for a slightly elevated pH (8.7) in one sample. Sequencing confirmed the identities of A. niger (573 bp) and F. poae (570 bp). The study highlights the presence of potentially harmful fungi in pupils’ drinking water, emphasizing the need for routine water quality surveillance and public health education.