Browsing by Author "Nambela, Lutamyo"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Determination of Dichlorodiphenyltrichloroethane (DDT) and Metabolites Residues in Fish Species from Eastern Lake Tanganyika(South African Chemical Institute, University of KwaZulu-Natal, 2018) Mahugija, John A.M.; Nambela, Lutamyo; Mmochi, Aviti J.In this study, the levels and status of dichlorodiphenyltrichloroethane (DDT) residues in fish samples collected from Eastern Lake Tanganyika were investigated. The analytes were determined using gas chromatography equipped with an electron capture detector (GC–ECD) and by gas chromatography-mass spectrometry (GC-MS). The compounds p,p’-DDE (4,4’-DDE), p,p’-DDD (4,4’-DDD), o,p’-DDT (2,4’-DDT) and p,p’-DDT (4,4’-DDT) were detected in all the samples, with total DDT concentrations ranging from 23 ± 8.3 to 339 ± 27 μg kg–1 fresh weight and 1736 ± 1388 μg kg–1 to 25 552 ± 4241 μg kg–1 lipid weight. The highest concentrations of total DDT were detected in Lates stappersii species. The ratios of the metabolites (DDD + DDE) to the parent compound (p,p’-DDT) were low (< 1) in all the fish samples, indicating exposure to fresh DDT. The concentrations of the DDT residues exceeded the extraneous maximum residue limit of 1.0 μg kg–1, indicating risks and concerns for public health and the environment because of the indication of fresh application of banned pesticides and bioaccumulation. There is need for continued monitoring of the residues in Lake Tanganyika environs and controlling the pesticides used in the area.Item FTIR ANALYSIS OF COTTON FABRIC DYED WITH NATURAL DYES(University of Dar es Salaam, 2016-09-01) Haule, Liberato; Nambela, Lutamyo; Samwel, JustineThe application of synthetic dyes has been questioned due to the associated negative impact of the chemicals used during dye manufacturing of the dyes. Scientists are searching for an alternative source of textile dyes whose sustainability is potentially better that the traditional synthetic dyes. Dyes from plants are have previously been researched and a dominant category of such dyes is the indigo dyes mainly used for dyeing of denim jeans. In Tanzania some entrepreneurs have successfully managed to extract dyes form dry leaves of certain plants and such dyes are used for the “tie –and dye” of cotton fabrics. While the chemical nature of such dyes remains the secret of the inventor, the chemical environment of the dye when applied in cotton fabric is yet established. In this paper the surface of cotton fabric dyed with locally manufactured dye were characterised by the use of Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) in order to understand the performance of the locally manufactured natural dyesItem Levels and distribution of pesticide residues in soil and sediments in Eastern Lake Tanganyika environs(International Formulae Group (IFG), University of Dschang, Cameroon, 2017) Mahugija, John A.M.; Nambela, Lutamyo; Mmochi, Aviti J.The aim of this study was to investigate the types, levels and distribution of pesticide residues in Eastern Lake Tanganyika basin in Tanzania. Soil and sediments samples were collected from various sites in Kigoma region. Analyses of cleaned sample extracts were performed using gas chromatographyelectron capture detection (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). Six pesticide residues and metabolites were detected, namely, p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD, diazinon and chlorpyrifos. DDT, DDD and DDE were the predominantly detected compounds in all of the samples. Diazinon and chlorpyrifos were detected in soil samples only. The highest concentrations of total DDT in sediments and soil ranged from 10.02 to 116 μg/kg dry weight (dw) and 7.5 to 564.2 μg/kg dw, respectively. Chlorpyrifos and diazinon had concentrations up to 36 and 184 μg/kg dw, respectively. The concentrations of DDT residues were greater in soil samples than in sediments. The highest concentrations of DDT residues were detected in soil samples. The ratios of (p,p'-DDE + p,p'-DDD)/p,p'-DDT indicated recent inputs in most samples. The study reveals that there were recent uses of DDT, diazinon and chlorpyrifos in the region. Continued use of DDT indicates risks and may result into serious environmental problems. The area therefore needs serious environmental monitoring.Item Pesticide residues in water from rivers and lakes in Lake Tanganyika basin, Tanzania(Hokkaido University Japan, 2015) Mahugija, John A.M.; Nambela, LutamyoThe aim of this study was to investigate the types, levels and distribution of pesticide residues in water in Lake Tanganyika basin, Tanzania. Water samples were collected from Kigoma region during April and June and analysed for pesticide residues. The pesticides and metabolites detected were p,p’-DDT, o,p’-DDT, p,p’-DDE and p,p’-DDD. The concentrations of total DDT in water were up to 200 and 221 ng/L in lakes and rivers, respectively. The ratios of (p,p’- DDE + p,p’-DDD)/p,p’-DDT indicate recent inputs in most samples. The study reveals that there is recent use of DDT in the region. Continued use of DDT indicates concerns and risks for public and environmental health. The area therefore needs serious environmental monitoring.