Lipid, heavy metal and pesticide contents of free range cattle slaughtered at Obinze Abattoir, Imo State, Nigeria
Date
2024-01
Authors
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Journal ISSN
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Publisher
Federal University of Technology, Owerri
Abstract
This study aimed at determining the lipid, heavy metal and pesticide contents in commonly consumed cattle meat parts obtained from Obinze Abattoir, Imo State, Nigeria. Cholesterol, fatty acid profile, heavy metals and pesticide concentrations were determined in cattle meat to evaluate the nutrient compositions and safety of regular consumption of these products. Nutrient composition was determined using standard methods. Pesticide and heavy metal levels were measured by gas chromatography (GC) and atomic absorption spectrometry (AAS), respectively. Forty-five samples comprising 15 each of torso, skin, stomach, lean meat and intestine were collected and analysed. The result of the cholesterol estimation showed that there were significant differences (p< 0.05) in cholesterol content between torso, stomach, skin and lean meat. Cholesterol content was found to be highest in the torso meat (115.2±6.48 mg/kg), followed by lean meat (94.7±2.27 mg/kg) and skin (79.3 ± 6.30 mg/kg) and lowest in the intestine (74.9 ± 2.33 mg/kg) and stomach (67.76 ± 5.69 mg/kg). The concentration of polyunsaturated fatty acid (PUFA) was higher than saturated fatty acids (SFA) in all meat parts which indicates that these meat parts have less risk hazard to human health. Oleic acid was the only monounsaturated fatty acid recorded in this study with highest concentration in torso (21.59± 6.13 mg/kg). Results of the heavy metal analysis obtained shows mean concentrations ranging from Mn (0.178±0.020 – 0.348±0.025 mg/kg), As (0.004±0.002 – 0.037±0.001 mg/kg), Cu (0.042±0.029 – 0.385±0.009 mg/kg), Fe (0.333±0.113 – 1.510±0.042 mg/kg), Zn (0.173±0.007 – 0.406±0.086 mg/kg), Ni (0.035±0.016 – 0.154±0.028 mg/kg), Cr (0.314±0.067 – 0.734±0.234 mg/kg), Pb (0.021±0.002 – 0.089±0.009 mg/kg), Co (0.021±0.004 – 0.049±0.010 mg/kg), and Cd (0.019±0.003 – 0.092±0.002 mg/kg). These were below the World Health Organization/Food and Agricultural Organization maximum permissible limits for heavy metals except for Fe, Cr and As. Pesticides analysis showed that 16 pesticides were detected across sample: DDT and its metabolites (pʹpʹ-DDE and pʹpʹ-DDD), chlordanes (gamma-chlordane and trans-nonachlor), heptachlor, lindane, endosulfan, hexachlorobenzene (HCB), biphenyl, dichlorobiphenyl and 4-4 bipyridinium dichloride, chlorpyrifos, dichlorvos and emamectin. No statistical differences at p<0.05 were observed for most pesticides detected. Heptachlor was the most abundant pesticide with the highest concentration recorded in the skin (2.16 ± 1.88 mg/kg), followed by torso (1.58 ± 1.38 mg/kg). Comparing with residue limits set by FAO/WHO and European Union, residual concentrations of heptachlor, lindane, HCB, biphenyl and chlorpyrifos recorded levels exceeding the maximum residue limits. This study revealed that there may be some benefits to human health not only in terms of essential fatty acids such as linoleic and linolenic acids, but also polyunsaturated fatty acids such as arachidonic, eicosapentaenoic and docosahexanoic acids. However, it also highlighted the potential risk associated with the presence of heavy metal and pesticides above tolerable limits, which significantly diminished the nutritional advantages consumers may otherwise derive from the consumption of these meats.
Description
This thesis is for the award of Master of Science (MSc.) in Biochemistry
Keywords
Cattle meat, cholesterol, fatty acid profile, heavy metals, pesticide residues, Department of Biochemistry
Citation
Amini, I. G. (2024). Lipid, heavy metal and pesticide contents of free range cattle slaughtered at Obinze Abattoir, Imo State, Nigeria (Unpublished Masters' Thesis). Federal University of Technology, Owerri , Nigeria