Bacteriological Quality of Abattoir Effluents Discharged into Water Bodies in Abuja, Nigeria
Objectives: Three operational types of abattoir, batch, slaughter and line abattoirs with their effluents (wastewater) were investigated for bacteriological quality in Lagos and Ogun states of Nigeria. The present study is a surveillance work to assess the housekeeping practices and the environmental impact of the three major abattoir types in Nigeria. Methodology and Results: Spread plate and multiple-tube fermentation techniques were used in the analyses. Total bacterial counts (TBC) on workers’ hands, butchering knives, slaughtering tables and floors ranged between 1.00 x103 and 4.67 x103cfu/ml while total coliform count (TCC) of the effluents ranged between 1.5 x 106 and 1.0 x 102 MPN/ 100ml of Faecal coliform (FC). The highest numbers of isolated organisms (% occurrence) were 42.0%, 21.9%, 21.9% and 14.3% for the Karra batch abattoir, RCCG Canaan land batch abattoir, Odo-eran slaughter slab and Ikenne line abattoir respectively. The following organisms were identified from the pure isolates contained in the samples from the various sources from the selected abattoir sites, namely, Citrobacter diversus, Erwinia chrysanthemi, Klebsiella oxytoca, Klebsiella pneumoniae, Serratia fonticola, Enterobacter aerogenes, Enterobacter intermedius, Escherichia coli. Conclusions and application of findings: The line slaughter facilities conform to the WHO guidelines on setting up of an abattoir. However, slaughter slabs often violate the rules of public health, inspection and marketing regulations while in batch abattoir facilities no rules or guidelines are followed. These differences in modes of operation are reflected in the present microbiological analyses. However, the TCC of effluents for all the abattoir types examined exceeded recommended limit for discharge into surface water in Nigeria. Adoption of best practices such as updating most (if not all) abattoirs in Nigeria to line type and better enforcement of available regulations regarding limits on effluents from industrial facilities is recommended to reduce the negative health and environmental impact of abattoirs in Nigeria.