scholarly journals Histo-toxicity of Corexit 9500 Dispersant on Gill and Liver of Clarias gariepinus (Burchell 1822)

Author(s):  
O. Taylorharry ◽  
A. P. Ugbomeh ◽  
K. N. O. Bob-manuel

The aim of this study was to assess the chronic toxicity of Corexit 9500 on histology of liver and gill of juveniles of Clarias gariepinus. Range finding tests were conducted over a 96-hr period after acclimatization of the test organisms in the C.P. Powell laboratory in the University of Port Harcourt, Nigeria. The test organisms 10/treatment were exposed to the following concentrations of Corexit 9500; 0.00 ml/L, 0.0125 ml/L, 0.025 ml/L and 0.05 ml/L in triplicate. Liver and gill were excised from fish every week for histological assay using standard methods. The LC50 at 96 hrs was 0.115 ml/L. The growth in length and weight of C. gariepinus was significantly higher in the control than the test treatments (p<0.05). Hyperplasias, necrosis of epithelial cells, inflammation of the secondary gill lamella and hypertrophic primary gill lamella were observed in the exposed gills. Hepatic lesions in the liver tissues of the fishes exposed to Corexit 9500 were characterized by hyperplasia, narrowing of the central vein and vacoulations. The alterations observed in the liver and gill tissues indicated that Corexit 9500 may have interfered with transamination and metabolic processes, with the possibility of affecting the physiological functions of the fish in an aquatic environment.

2020 ◽  
Vol 29 (1) ◽  
pp. 111-121
Author(s):  
K.N.O. Bob-Manuel ◽  
A. Ugbomeh ◽  
O. Taylorharry

The effects of sub-lethal concentrations of Corexit 9500 on growth and condition factor of juveniles of Clarias gariepinus was investigated after 21days, in 2018. 160 fishes were used as test organisms with a loading of 10/treatment and were exposed to 0.00, 0.0125, 0.025 and 0.05 ml/L concentrations of Corexit 9500. Treatments were in triplicate and Complete Randomised Design was adopted. The growth in length and weight of C. gariepinus was significantly higher in the control than the test treatments (P<0.05). The increase in weight of the control was significantly different from the three treatments. Temperature was not significantly different (P>0.05); however, the DO of control was significantly higher (P < 0.05) than that of the treatments, with the lowest DO in the 0.05ml/l treatment. pH was acidic for all treatments including the control but was more acidic with increasing concentration of Corexit 9500. The pH value for each treatment was significantly different (P<0.05). The conductivity was significantly different from each other (P<0.05) with higher values at the 0.025 ml/L concentrations. The condition factor (K) decreased with increasing toxicant concentration and was significantly different (P<0.05) at 0.0125ml/L and at Weeks 2 and 3 of 0.05 ml/L. Corexit 9500 dispersants should be appropriately assessed before deployment, and their use near fish breeding grounds should be avoided. Key words: Clarias gariepinus, dispersant, growth, physicochemical parameters, sub-lethal


2020 ◽  
Vol 4 (2) ◽  
pp. 41-45
Author(s):  
Sadam Sulaiman Indabo ◽  
Rufai Zakari

Dermestes maculatus is a major pest of stored fish in Nigeria, fish is preserved with highly persistent synthetic chemicals. There have been an increasing effort at developing plant-based toxicants that are environmentally friendly. Therefore, this study was conducted to screen the leaf extract of Azadirachta indica for phytochemical constituents. The efficacy of the methanolic leaf extract of the plant against D. maculatus was also evaluated. The leaves of A. indica were obtained, processed and taken to laboratory for methanolic extraction. Phytochemical screening was carried out to identify saponins, flavonoids, alkaloids, tannins, steroids, cardiac glycosides, glycosides, triterpenes and carbohydrates using standard procedure.  Both clean and infested samples of smoke-dried Clarias gariepinus were purchased from Sabon Gari Market, Zaria. The infested samples were used as initial source of D. maculatus larvae. Range finding test was carried out prior to the bioassay. During the bioassay, clean un-infested fish samples were weighed and introduced into kilner jars and respective dosages of 0.2g, 0.4g, 0.6g and 0.8g of extract were added. Another set of fish samples without the extract were maintained as control. The experiment was arranged in Completely Randomized Design with three replicates. Fifteen larvae of D. maculatus were introduced into both treated and control containers and covered. Mortality was recorded after 24, 48, 72 and 96 hours. Data obtained revealed an increase in mortality with increasing dose and time. Mortality ranged from 1.67 to 11.00. Therefore, leaf extract of A. indica should be incorporated in the development of larvicide against D. maculatus.   


2014 ◽  
Vol 5 (4) ◽  
pp. 209-212
Author(s):  
Braimoh Omoigberai Bashiru ◽  
Umanah Ayamma Udo

ABSTRACT Objectives Cigarette smoking is recognized as the most important environmental risk factor in periodontitis and also an important risk factor for oral cancer. The aim of this study was to determine the prevalence of cigarette smoking and awareness of oral health problems of tobacco use among university students in Port Harcourt, Nigeria. Materials and methods The study population consisted of 360 young adults: 188 (52.2%) males and 172 (47.8%) females. Participants answered questions regarding demography, smoking behavior, attitude and on oral effect of smoking. Data were analyzed using IBM SPSS (New York, USA) statistics version 20.0 and test of significance done using Chi-square. Results The overall prevalence of smoking was 78 (21.7%): 52 (27.7%) in males and 26 (15.1%) in females. Males significantly smoked more than females (p = 0.002). Fifty-one (65.4%) of the current smokers commenced smoking in secondary school, 39 (50%) had smoked for 6 to 10 years, 54 (69.2%) consumed one to five sticks of cigarettes per day and among those who quitted smoking, 39 (52%) stopped smoking for health reasons. While 262 (72.8%) were ignorant that smoking was harmful to oral health, 223 (61.9%) and 278 (77.2%) respectively could not identify smoking as a risk factor for oral cancers and gum disease. Conclusion Though majority of the students were aware of the negative impact of smoking on general health, most of them were ignorant of the effect on oral health. Therefore, shared risk approach should be employed to inform, guide and educate the public on the effects of tobacco and in the campaign against its use. How to cite this article Bashiru BO, Udo UA. Cigarette smoking and Awareness of Oral Health Problems of Tobacco use among Students at the University of Port Harcourt, South- South Nigeria. World J Dent 2014;5(4):209-212.


2015 ◽  
Vol 32 (01) ◽  
pp. 022-028 ◽  
Author(s):  
S. Abalaka ◽  
M. Fatihu ◽  
N. Ibrahim ◽  
S. Ambali

Abstract Introduction: Histopathological effects of ethanol extract of Adenium obesum stem bark on the liver of Clariasgariepinus was investigated over a 96-h exposure period as an effective organic piscicide. Materials and Methods: An acute static toxicity bioassay was performed after a preliminary concentration range finding test was conducted. Results: Exposed fish showed adaptation behavioural changes with those of respiratory distress and abnormal nervous signs of toxicity, which was concentration-dependent. Mortality was recorded in some of the exposed fish while a median lethal concentration of 7.15 mgL-1 was established for the extract in the exposed fish. Non-significant (p>0.05) changes were recorded in serum aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase activities of the exposed ish. Moderate liver damage was observed in the exposed fish based on the degree of tissue change (DTC) grading where significant (p<0.05) differences were observed between the DTC of the exposed groups and the control. Conclusion: Ethanol extract of A. obesum stem bark was toxic to the exposed fish with evidence of hepatotoxicity and therefore, can be used to eradicate the hardy C.gariepinus from aquatic environments.


Author(s):  
H. O. Stanley ◽  
C. N. Eze

A study about the bacteriological and physicochemical quality of borehole water at the University of Port Harcourt was carried out. Eight water samples was pooled from NUH Block B (Under graduate Hostel), Nelson Mandela Block B (Undergraduate Hostel), Intercontinental Hostel (Post Graduate Hostel), Donald Ekong Block C (Post graduate Hostel), Clinical Hostel, Staff quarters (Opposite Uniport Bottling plant), Dan Etete (Undergraduate Hostel) and Gambiama Staff quarters designated as Sample 1 to sample 8 respectively. Physical examination was conducted to as the sanitary and hygiene practices within the collection area. It was observed that the undergraduate hostels had the least sanitary practice. Total counts of heterotrophic bacteria count showed that the highest bacterial count was recorded from Sample 2 with bacterial count of 2.3x104 CFU/ml while the least bacterial count was recorded from sample 8 with bacterial count of 3.0x102 CFU/ml. The isolated bacterial species from the water sources were identified as Bacillus sp., Micrococcus sp., E. coli., Serratia sp., Staphylococcus sp., Enterobacter sp., Citrobacter sp. The presence of coliform bacteria in the sampled water source does not comply with the World Health Organization (WHO) standard for coliform bacteria of zero total coliform per 100 ml of water. The borehole water samples collected had pH values within 5.9-6.85 which does not comply with the WHO recommended range for drinking water standards which should fall between ≥7 to ≤9.2. Nitrate concentration as observed amongst the eight water samples was below the WHO standard of 50mg/l. The Total dissolved solutes was below 0.01 in all the tested waters samples. This study has revealed that borehole water from sampled sources within the University of Port Harcourt is not fit for human consumption without adequate treatment.


Sign in / Sign up

Export Citation Format

Share Document