Assessment of the Toxic of a Cypermethrin, Deltamethrin and Cyhalothrin Insecticide on the Fingerlings of Clarias gariepinus (Burchell, 1822) (Published)
Clarias gariepinus fingerlings of 2.620 ± 0.370g and 6.480 ± 0.598cm mean weight and length were exposed to a Cypermethrin, Deltamethrin and Cyhalothrin insecticide at concentrations of 0.0045, 0.0085, 0.0110, 0.0125 and 0.015ml/L in triplicates with a control (0ml/L) for 96hours. To evaluate the effects on the pH, dissolved oxygen-DO, temperature, salinity, total dissolved solids-TDS, and electrical conductivity-EC of the test media; fish mortality (%), the lethal concentration (96hrLC50) using Probit Plot, the risk of the insecticide, and the oxidative stress indices (the antioxidants- Superoxide dismutase- SOD, Catalase activity- CAT, Glutathione-S-transferase- GST and Malondialdehyde- MDA). The mean ± SD of the data obtained were analyzed and tested using One-way ANOVA. Results obtained showed that, the variations (at p<0.05) in the values of the parameters analyzed were concentration-dependent. The values for the TDS (92.00±1.0 to 124.50±2.50mg/L), EC (183.50±1.50 to 249.00±5.00µS/cm) and salinity (133.76±3.20 to 159.36±3.20mg/L) were most affected by the exposure concentrations compared to the control; the EC values were higher than the WHO Guidelines. Mortality was 6.67, 10.0, 56.67, 30.0 and 63.33% in the concentrations respectively. The 96hrLC50 extrapolated using Probit was 0.00128ml/L, a value that implied high toxicity of the insecticide which was validated by the risk determined to be >1, indicative of high risk. The oxidative stress indicators- SOD, CAT, and GST values determined in the Kidneys and liver of the fish showed reductions with increase in concentration while the MDA had converse values. These values indicated physiological and pathological abnormalities, and oxidative stress in the fish.
Keywords: Assessment, cyhalothrin insecticide, cypermethrin, deltamethrin, fingerlings clarias gariepinus, toxic
An Examination of the Problems encountered in applying quality assessment system by Lagos State Building Contractors (Published)
Citation: Ngozi Marykate Okoye, Kevin Chuks Okolie ; Okongwu Ikechukwu Michael (2022) An Examination of the Problems encountered in applying quality assessment system by Lagos State Building Contractors, British Journal of Environmental Sciences, Vol.10, No.2, pp. 13-22
The construction industry contributes 1% employment opportunities to Nigerians (Ding, 2008). According to the World Bank, an active industry should contribute at least 3.2% of the employment opportunities in the country. The aim of this study is to examine the problems encountered in applying quality assessment system in Lagos state. In order to realize this aim, the study examined challenges encountered by contractors..The study employed a descriptive case study design where data was collected from senior managers, project managers, engineers, architects, quantity surveyors, and technical managers working with building construction companies in the Lagos Metropolitan Area using the mixed method approach. Quantitative data was collected using questionnaire from 109 randomly selected participants and analysed using descriptive and inferential statistics. Qualitative data was collected through interviews with 9 purposively selected respondents and analysed using the thematic analysis technique. The study shows challenges encountered by Contractors to include: Lack of adequate resources, inadequate skills and expertise, Casual/ temporary nature of construction workforce, Internal resistance, Lack of flexibility in existing tools and approaches etc. The study concludes that the most significant challenge encountered by local contractors when it comes to quality assessment is the lack of adequate resources and the study also identified staff training and education, integration of information technology, and increased involvement of senior leaders as the most important issues that they would like their organization to improve so as to increase the effectiveness of the quality assessment process.
Keywords: Assessment, Building Contractors, Examination, Lagos State, Quality, System