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Water is very important to the existence of humans though could also serve as vehicle for pathogenic organisms and dangerous organic and inorganic matters. The physicochemical and microbial analyses of selected borehole water samples in Awka residential areas were conducted with the aim of ascertaining suitability or otherwise for human consumption. The total hardness, pH, alkalinity, some common elements and presence of toxic metals were determined by standard methods of American Public Health Association. The presence of microorganisms in the water samples was also determined. Results of the physicochemical analysis of the borehole water samples showed a mean pH value of 5.52 below the WHO standard of 6.5 - 8.5 and mean total hardness of 150 ppm greater than the WHO standard of 70 ppm. The microelements such as manganese, zinc, lead, selenium, nickel and cadmium were found to be below detectable levels in the water samples. Five bacteria species were isolated and identified in the water samples as Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli and Klebsiella pneumoniae. The physicochemical properties and the bacteria load of most of the water samples indicate that they were unfit for human consumption as the samples were outside WHO reference standard for potable water suggesting a need for increased awareness for improved sanitation and hygiene practices in the state.

This work explored the effect of African Walnut Shell Particle (AWSP) (Tetracarpidium conophorum) on the properties of recycled low density polyethylene (rLDPE) composite. rLDPE/ AWSP composite were prepared via compressive moulding techniques using AWSP of sizes 300 and 600μm respectively. Composite design of experiment and analysis of variant (ANOVA) were employed for optimization. Mechanical and morphological analysis of the composite were studied. rLDPE reinforced with AWSP of particle size 300 μm exhibited better tensile strength, modulus of rupture (MOR) and modulus of elasticity (MOE) than those of 600 μm. Morphological analysis showed that uniform distribution of the Walnut shell particulates in the microstructure of the composite is the major factor responsible for the improvement in the mechanical properties. Optimality occurred at a press temperature of 206.465°C, press time of 10 min, press pressure of 7 MPa yielding a tensile strength of 14.082 MPa, MOR of 17.019 MPa and MOE of 755.028 MPa for 300 μm particle sized composite whereas for 600 μm size, it was achieved at press temperature of 199.993°C, press time of 6 min, press pressure of 7 MPa giving a tensile strength of 11.252 MPa, MOR of 15.401 MPa and MOE of 459.531 MPa respectively. The result from the optimization met the standard for interior and exterior mirror casing of automobiles.