Effects of Crude Oil contaminated Water on the reproductive system of Female Wistar Rats

The rising level of infertility in the females have been associated with environmental pollutants and one such pollutants is crude oil. Crude oil pollution occurs in the Niger-Delta region of Nigeria and interaction with this toxicant by both humans and animals may adversely the female reproductive system. This study was designed to investigate the effect of crude oil contaminated water on reproductive functions in female Wistar rats. Fifteen (15) female rats weighing between 140g-230g were used for this study and the rats were divided into three (3) groups (1, 2 and 3) and each group had five rats. Group 1 was the control group while group 2 and 3 were the test groups receiving 2.5mls and 5mls of crude oil contaminated water twice daily for four weeks. The stages of Oestrus cycle of the rats were checked daily. The rats were sacrificed after four weeks and the blood collected were used for hormonal assays (Follicle stimulating hormone (FSH), Luteinizing hormone (LH), Testosterone). The uterus and ovaries were used for histology (Haematoxylin and Eosin staining), Superoxide dismutase (SOD) activity and Malondialdehyde (MDA) concentration. The results were analyzed using GraphPad Prism software for windows and data were expressed as mean±standard error of mean. Statistical significance was accepted at p<0.05. There was no significant changes (p>0.05) in the weights and relative reproductive organ weights (uterus and ovary) of among the three groups. FSH and LH in the test group of rats fed with crude oil contaminated water when compared with the control were not statistically significant (p<0.05). Oestradiol was significantly lower (p<0.05) in the test group whereas progesterone and progesterone-oestradiol ratio was significantly elevated (p<0.05) in the test groups when compared with the control. There were degenerative changes in the ovaries and uterus of rats fed with crude oil contaminated water when compared with the control. SOD was significantly reduced (p<0.05) in the test group while MDA was elevated in the ovaries and uterus of the test group. The oestrus cycle was irregular in the test groups.   Crude oil contaminated water has endocrine disrupting effects on the female reproductive system as well as inducing oxidative stress and this may adversely affect female reproductive functions and fertility. KEY WORDS: Crude oil contaminated water, Endocrine disruptor, Female reproductive functions, Oxidative stress DOI: 10.7176/JMPB/72-05 Publication date: June 30th 202

Dissolution Control of Mg by Cellulose Acetate–Polyelectrolyte Membranes

Cellulose acetate (CA)-based membranes are used for Mg dissolution control: the permeability of the membrane is adjusted by additions of the polyelectrolyte, poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA). Spin-coated films were characterized with FT-IR, and once exposed to an aqueous solution the film distends and starts acting as a membrane which controls the flow of ions and H2 gas. Electrochemical measurements (linear sweep voltammograms, open-circuit potential, and polarization) show that by altering the CA:PDMAEMA ratio the dissolution rate of Mg can be controlled. Such a control over Mg dissolution is crucial if Mg is to be considered as a viable, temporary biomedical implant material. Furthermore, the accumulation of corrosion products between the membrane and the sample diminishes the undesirable effects of high local pH and H2 formation which takes place during the corrosion process.Peer reviewe

Inhibition effect of Vernonia amygdalina extract on the corrosion of mild steel reinforcement in concrete in 0.2 M H2SO4 Environment

Inhibition effect of Vernonia amygdalina (bitter leaf) extract on the corrosion behaviour of embedded mild steel rebar in concrete immersed in 0.2% H2SO4 solution was investigated by potential measurement, pH and gravimetric methods using the extracts concentrations of 25, 50, 75, and 100%. The results were further analysed using the two-factor ANOVA test. Potential measurement was performed using a digital voltmeter and a copper/copper sulphate reference electrode. Compressive strength of each block sample was determined after the experiments. Weight loss values were obtained from the gravimetric method, and the inhibitor efficiency was computed from the corrosion rate of each of the tested samples. Results showed that varied concentration of V. amygdalina and the test exposure time significantly affect both the corrosion potential of embedded steel rebar in concrete and the pH of the medium. The extracts gave appreciable corrosion inhibition performance of the embedded steel rebar at 25 and 50% concentrations with the weight loss of 500 (0.5 g) and 400 mg (0.4 g) and corrosion rates values of 0.000240 and 0.000180 mm/ yr, respectively. The highest inhibition efficiency (60.68%) was achieved at 50 and 39.94% at 25% concentrations, respectively. The 100 and 75% concentrations gave negative inhibitor values of �51.52 and �20.11%. The ANOVA test confirmed the results at 95% confidence, and further showed that concentration of V. amygdalina had greater effect on potential and pH measurement

Treated Rhizophora mucronata tannin as a corrosion inhibitor in chloride solution

Treated Rhizopora mucronata tannin (RMT) as a corrosion inhibitor for carbon steel and copper in oil and gas facilities was investigated. Corrosion rate of carbon-steel and copper in 3wt% NaCl solution by RMT was studied using chemical (weight loss method) and spectroscopic (FTIR) techniques at various temperatures in the ranges of 26–90C. The weight loss data was compared to the electrochemical by the application of Faraday’s law for the conversion of corrosion rate data from one system to another. The inhibitive efficiency of RMT was compared with commercial inhibitor sodium benzotriazole (BTA-S). The best concentration of RMT was 20% (w/v), increase in concentration of RMT decreased the corrosion rate and increased the inhibitive efficiency. Increase in temperature increased the corrosion rate and decreased the inhibitive efficiency but, the rate of corrosion was mild with RMT. The FTIR result shows the presence of hydroxyl group, aromatic group, esters and the substituted benzene group indicating the purity of the tannin. The trend of RMT was similar to that of BTA-S, but its inhibitive efficiency for carbon-steel was poor (6%) compared to RMT (59%). BTA-S was efficient for copper (76%) compared to RMT (74%) at 40% (w/v) and 20% (w/v) concentration respectively. RMT was efficient even at low concentration therefore, the use of RMT as a cost effective and environmentally friendly corrosion inhibiting agent for carbon steel and copper is herein proposed