The use of heavy metals load as an indicator of the suitability of the water and fish of Ibiekuma Stream for domestic and consumption purposes

The levels of Cd, Cr, Cu, Pb and Zn in the water and fish from Ibiekuma Stream, Ekpoma, Nigeria were determined at two locations (Upstream and Downstream) in order to ascertain their suitability for consumption and other domestic uses. Atomic Absorption Spectrophotometry was used to measure the metal levels. Seasonal (dry and wet seasons) levels were also determined. The results showed Zn mean levels were highest with 1.12 ± 0.51 mg/l in water and 45.5 ± 7.46 mg/kg in fish. Minimum levels were 0.005 ± 0.002 mg/l (Cd and Pb) in water and 0.70 ± 0.22 mg/kg (Cd) in fish. Pb was not detected in fish. Spatially, upstream location levels were generally higher than downstream levels for all the metals in both water and fish. Dry season levels were also generally higher for all samples and at both locations. The consumption of the fishes of the stream requires stringent precautionary measuresbecause of the high levels of Cr and Cu which exceeded limits in food fish and could therefore pose some health risks. It was also observed that all metal levels in water were within drinking water limitsand global background levels for surface fresh water. The implication of these findings is that the water of the stream could be used for drinking and other domestic purposes

Heavy metals concentrations in the offal, gill, muscle and liver of a freshwater mudfish (Parachanna obscura) from Ogba River, Benin city, Nigeria

This study assessed and monitored the concentrations of Cu, Mn, Zn, Cd, Cr, Ni and Pb in the gills, offal, muscle and liver of a commercially important mudfish (Parachanna obscura) from Ogba River, BeninCity, Nigeria between January and December, 2005. The same metals were also determined in the water of the river. The results revealed that the concentrations of all the metals in the tissues (offal, gills,muscle and liver) were higher than the concentrations of the metals in water and indicated bioaccumulation. The concentrations of all the metals in water were below WHO and FEPA recommended limits and suggested that the water of Ogba River was suitable for drinking, but theconcentrations of Cu, Mn, Cr, Ni and Pb in all fish tissues exceeded these limits and indicated that the fishes of Ogba River, as far as these metals were concerned, were unfit for human consumption.Consequently, close monitoring of metals pollution and the consumption of the fishes of Ogba River is recommended with a view to minimizing the risks to health of the population that depend on the river fortheir water and fish supply

Heavy metal concentrations in Malapterurus electricus and Chrysichthys nigrodigitatus from Ogba River in Benin City, Nigeria

The concentrations of heavy metals in two tropical fish species (Malapterurus electricus and Chrysichthys nigrodigitatus) from Ogba river in Benin City, Nigeria, were investigated between November 2002 and October 2003 in order to ascertain the pollution status of the river. The results showed varying levels of accumulation of Cu, Mn, Zn, Pb, Cr, Ni, and Cd in the fishes. The levels of Cu,Mn, Cr and Ni, in both fishes were higher than the WHO and FEPA recommended maximum allowable standards in food fish, while those of Zn, Pb and Cd were lower than the standards. The results suggest that the Ogba river system is contaminated with heavy metals and the consumption of fishes of the river could pose health hazards to man. Metal levels in water in Ogba River are lower than the recommended limiting standards and could be considered safe for drinkin

Water pollution: A review of microbial quality and health concerns of water, sediment and fish in the aquatic ecosystem

This paper reviewed aquatic ecosystem pollution with particular reference to pathogens in water, sediment and fish and their human health concerns. It highlighted the historical perspective of the relationship between microbes and humans regarding the “ranging war” between them, arising fromthe reckless exploitation of the biosphere by humans and the resultant “revolt” by microbes in the form of various pathogenic diseases that now plague mankind. Also highlighted are pathogens and diseases in both wild and cultured fish, citing reported cases in Nigeria to include Samonella, Shigella and Leptospira spp., Proteus vulgaris, Escherichia coli, Citrobacter diversus, Pseudomonas florescens, Aeromonas hydrophilla, Staphylococus aureus, Klebsiella aerogenes, Edwardsiella tarda and Flexibacter columnaris. Some human diseases contacted from contaminated/infected fish and fisheries’ products that have been reported in Nigeria were reported to include: food poisoning and gastroenteritis, diarrhea, bacillary dysentery, typhoid and paratyphoid, clonorchiasis and superficialwound infections and ulcers. In conclusion, the paper reviewed the modes of infection of water related and fish-borne diseases of human health concerns and recommended ways to ameliorate their infection and spread

Physicochemical evaluation of bore-hole water from selected fish farms in Edo State, Nigeria

This study investigated the physical and chemical properties of water from bore-holes in selected fish farms in the three districts of Edo State, Nigeria. Sample collection, treatment and determination of physical and chemical properties were according to approved standards. The results showed that all the parameters analyzed were within the required standards for aquaculture and drinking purposes, except pH which was slightly acidic, alkalinity in Edo South which was very low, and the metals Mn and Pb whose concentrations exceeded the standard limits for drinking water. Based on the acceptable levels of most of the parameters, it was concluded that the water of the study area was suitable for aquaculture, drinking and other domestic purposes. However, because of the pH and the heavy metals Mn and Pb, it was recommended that the water be treated with lime before use especially in aquaculture facilities, in order to increase pH and possibly reduce metal concentrations to tolerable limits through precipitation and or adsorption, to sediment particles and thus lead to production of suitable fish for consumers

Impact of urban wastewaters on the diversity and abundance of the fish population of Ogba River in Benin City, Nigeria

The effects of urban wastewaters on the diversity and abundance of the fish population of Ogba River in Benin City, Nigeria were assessed and monitored at 5 sample stations between November 2007 and October 2008. The physico-chemical properties of the water were also monitored during the period. A total of 486 individual fishes made up of 26 different species were recorded, with Clarias macromystax (Clariidae), Malapterurus electricus (Malapteruridae), Xenomystus nigri (Notopteridae), Hemichromis fasciatus and Oreochromis niloticus (Cichlidae) being the dominant species. The water chemistry, fish species diversity and abundance at the study stations were different and were negatively impacted upon by urban wastewaters pollution. It was also revealed that the fish communities of the river were under stress and not in good condition. Consequently, a close monitoring of all effluent discharges and other probable stress-inducing factors in Ogba River is recommended

Heuristic framework for parallel sorting computations

Parallel sorting techniques have become of practical interest with the advent of new multiprocessor architectures. The decreasing cost of these processors will probably in the future, make the solutions that are derived thereof to be more appealing. Efficient algorithms for sorting scheme that are encountered in a number of operations are considered for multi-user machines. A heuristic framework for exploiting parallelism inherent in some of these schemes are worthy of investigation and valid suggestions are given for adequate implementation by associating processors in a multiprocessor platform. This exercise involves a closer investigation of the associated savings in employing simultaneous sorting techniques for, say N2 processors. A deterministic o(log2N) time algorithm using Nlog2N processors will substantially reduce the run time for a sorting scheme and is considered to be asymptotically optimal. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 413-42

A software for the RSA Encription

In Omokaro 2003[12], we extended the RSA Congruence to a finite number of primes. The extended RSA Cryptosystem was later obtained in Omokaro 2004[13] as an analogue of the RSA Cryptosystem to obtain the extended RSA Cryptosystem. In this work we provide a software for the enciphering of data in RSA cryptosystem Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 423-43