Abstract

Bioremediation of Waste Water from an Industrial Effluent System inNigeria Using Pseudomonas aeruginosa: Effectiveness Tested on AlbinoRats

Akehinmi Michael Olawale

The bioremediation potential of Pseudomonas aeruginosa in removing some heavy metals from industrial effluent waste water in Lagos state, Nigeria was investigated. The effectiveness of this bioremediation was tested on albino rats. The common heavy metals known to be pollutants in oil-laden wastewater tested for in the wastewater are Cadmium (Cd), Chromium (Cr), Nickel (Ni), lead (Pb), Selenium (Se), Arsenic (Ar) and Zinc (Zn). These metals are poisonous to the body system when used. Having determined the concentrations of these metals in the effluent waste water by Atomic Absorption Spectrophotometric test, the results revealed that that Pb, Se, As and Cd are present at concentrations 0.2843 parts per million (ppm), 19.418 ppm, 5.02 ppm and 0.104 ppm respectively. These values fall out of the range required by World health Organization (WHO) standard. Nickel and Cr are present at concentrations of 0.070 and 0.050 ppm and were found to be within the range of WHO standard. Zinc was not detected at all.
The raw water was first treated with live catfishes and Albino rats respectively to determine the effect of the contaminants on both aquatic and terrestrial animals. It was observed that the two catfishes died 33hrs and 36hrs respectively after introduction into the raw water, while the two albino rats died 10 days after introduction into the water. Having detected these effects, the cultured microorganism, Pseudomonas aeruginosa with some nutrients were introduced into the wastewater for bioremediation process. This was compared to another set of experiment involving only the introduction of nutrients without the cultured microorganisms.
At the end of the fifteen (15) experimental days, the resulting bioremediated water having the cultured microorganisms shows that the concentrations of Lead (Pb), Selenium (Se), Arsenic (As), and Cadmium (Cd) had reduced to 0.0100 ppm, 0.0110 ppm, 0.0100 ppm, and 0.0100 ppm respectively. This implies percentage degradation of 96.43%, 99.94%, 99.80% and 90.38% respectively compared to the one with nutrients only having percentage degradation of 79.49%, 90.12%, 86.83% and 67.26% respectively. The resulting bioremediated water using Pseudomonas aeruginosa was then treated with a live albino rat for forty days in order to verify the removal or reduction of the toxic substance it contained before the experiment. Surprisingly, the rat did fine in good health condition. This concludes the bioremediation potential of Pseudomonas aeruginosa.