Browsing by Author "Patiri, Gloria"

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    Heavy metals and lambda-cyhalothrin levels in prawns, water and sediments along the Indian Coastline of Tanzania
    (International Journal of Biosciences, 2019-04-30) Patiri, Gloria; Makule, Edna; Matemu, Athanasia
    Heavy metals and pesticide residues in prawns, water and sediments, and sources of contamination were determined. Prawns, sediments and water samples were collected from agricultural farms and estuarine, along the coastline of Indian Ocean in Kisiju, Bagamoyo and Kilwa zones in Tanzania. The concentration of heavy metals; zinc (Zn), lead (Pb) and cadmium (Cd) was determined using Atomic Absorption Spectrophotometry (AAS), and Direct Mercury Analyzer (DMA) for mercury (Hg). Gas Chromatography-Mass Spectrophotometry (GC-MS) was also used to analyze for pesticide residues. Data on demographic characterization and sources of aquatic pollution were obtained through structured questionnaires. Results indicated that, fertilizers (60.7%), pesticides (59.8%) and herbicides (60.7%) were the main sources of aquatic pollution. Cyberdip and Utupa were the chemicals used in prawns. The distribution of heavy metals mean concentrations in prawns and sediments were found to be in order Zn>Pb>Cd>Hg, and Pb>Zn>Cd>Hg in water. Lambda-cyhalothrin was the only pesticide residue detected in prawns and sediments and not detected in water. Significant high levels of lambdacyhalothrin in sediments were detected from Kisiju (16.49±2.36mg/kg) and Kilwa (12.21±3.24mg/kg) respectively. On the other hand, lowest Lambda-cyhalothrin level in prawns was detected in Kisiju (2.26±0.51mg/kg) and Kilwa (0.28±0.40mg/kg). Presence of heavy metals and Lambda-cyhalothrin indicate marine pollution. Marine pollutants may impair quality and safety of prawns and by-products to the public health. Monitoring of agricultural and other anthropogenic activities in the area especially in the Rufiji delta and around the mangroves where prawns spawn is inevitable.
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    Heavy metals and pesticide residues as quality determinants for sustainable management of prawns along the Indian coastline of Tanzania
    (NM-AIST, 2020-05) Patiri, Gloria
    The presence of heavy metals and pesticide residues in prawns, water and sediments, were determine. Prawns, sediments and water samples were collected along prawns fishing zones in the Indian coastline of Tanzania. Zinc (Zn), lead (Pb) and cadmium (Cd) were analyzed using Atomic Absorption Spectrophotometry (AAS). Direct Mercury Analyzer (DMA) was used for mercury (Hg) analysis. Pesticide residues were analyzed by Gas ChromatographyMass Spectrophotometry (GC-MS). Information on stakeholder’s perception on the sources of aquatic pollution was collected using a structured questionnaire. Results indicated that, fertilizer (60.7%), pesticides (59.8%) and herbicides (60.7%) were the main sources of aquatic pollution. Cyberdip and Utupa-mixed local herbs were the chemicals used in prawns fishing. Heavy metal contaminants were predominant in sediments followed by prawns, and water. The heavy metals were highly concentrated in prawns and sediments in the order of Zn > Pb > Cd > Hg, and Pb > Zn > Cd > Hg in water respectively. Lambda-cyhalothrin was the only pesticide residue detected in prawns and sediments but not in water. Lambdacyhalothrin levels detected in prawns from Kisiju and Kilwa were 5.6 – 45.2 folds above the maximum acceptable limits. Lambda-cyhalothrin levels in sediments was 175; 4070 and 4432 folds higher than the maximum acceptable level in Bagamoyo, Kilwa and Kisiju respectively. Presence of Zn, Pb and lambda-cyhalothrin beyond acceptable limits in prawns and sediments may indicate marine pollution. The maximum acceptable level of lambdacyhalothrin in sediments is 0.00372 mg/kg and the maximum acceptable level of lambdacyhalothrin for prawns is 0.05 mg/kg. These pollutants may impair quality and safety of prawns and by-products which is a risk to the public health. Therefore, monitoring of agricultural and the anthropogenic activities around prawn fishing areas is inevitable.