MICROBIAL LOAD, AFLATOXIGENIC PROPERTY AND HEAVY METALS IN SOIL CONTAMINATED WITH CASSAVA WASTEWATER IN ODEDA LOCAL GOVERNMENT AREA, OGUN STATE
Keywords:
Manihot esculenta; effluent; mycotoxins; soil; toxigenicity,Abstract
Environmental degradation poses a formidable challenge to sustainable development, emerging as one of the most significant threats. Cassava processing, a widespread human activity in both rural and urban centers in Nigeria and other regions, stands out as a potential contributor to environmental degradation. The study aimed to determine the microbial load, aflatoxigenicity and heavy metals in soils contaminated with cassava wastewater. Cassava wastewater-contaminated soil samples were collected from five sources in Odeda Local Government. The samples were collected in a sterile zip-lock bag and transferred to the laboratory. Standard microbiological procedures were employed for microbiological analysis; the screening for aflatoxigenicity in fungal isolates was performed on yeast extract agar and examined using an Ultraviolet (UV) spectrophotometer. Metallic tests were conducted as part of the assessment. Statistical analysis was conducted using the SPSS software. Results revealed varying degrees of microbial contamination in the samples. Fungi isolated from the samples were: Aspergillus niger, Aspergillus flavus, Fusarium sp, and Rhizopus sp. Bacteria isolated were: Bacillus cereus, Staphylococcus sp, and Pseudomonas. Fungi and bacteria counts in the soil samples exceeded a feasible counting limit. Aflatoxigenicity screening affirmed that about 40% of the isolates were toxigenic. The study underscores the significance of implementing effective post-harvest handling practices for cassava to reduce contamination, thereby preventing environmental pollution and degradation.
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