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Title:	Concentrations of heavy metals in tissues and eggs of avian (Gallus gallus domesticus and coturnix coturnix japonica) and evaluation of the toxic effects in chicken
Authors:	Salwa A. Abduljaleel (P54245)
Supervisor:	M. Shuhaimi Othman, Prof. Dr.
Keywords:	Heavy metals Chicken Toxic Toxicology
Issue Date:	27-Jun-2013
Description:	Environmental pollution is one of the hazards of modern age. The determination of heavy metals in domestic bird tissues is required, considering that metals are one of the hazardous contaminants in the environment affecting populations of birds, which are then consumed by humans as food. Domestic avian samples and eggs were collected from a poultry farms at Semenyih, Selangor, Malaysia, from May 2010 to April 2011. In this work, the concentration of essential and nonessential heavy metals, namely, aluminum (Al), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), and lead (Pb), were measured using inductively coupled plasma mass spectrometry (ICP-MS). The present study aims to detect the levels of 12 heavy metals in six tissues, including pectoral muscle, liver, lung, gizzard, blood, and feather for 12 months. In addition, this study evaluates health risks to the local population through chicken consumption. The intake rates of heavy metals were estimated based on metal concentrations in chicken muscle, liver, and egg, which were subsequently correlated with daily chicken consumption. Moreover, this study also investigates the effects and toxicity of four selected heavy metals (Cd, Pb, Zn, and Ni) on egg hatchability and chick survival. Large intra- and inter-species variations in heavy metals concentrations between the tissues of the same bird and between species were observed. Generally, essential heavy metals, such as Fe, Zn, Cu, Mn, Cr, Se, and Ni occurred in high concentrations in the tissues of the two species. Meanwhile, non-essential heavy metals, namely, Cd, Pb, and As were observed in low concentrations in both chicken and quail tissues. Among the six tissues, the feather showed higher concentrations of heavy metals, such as Al, Cr, Co, Ni, Zn, Cd, and Pb. Meanwhile, pectoral muscle accumulated the least heavy metal concentrations among the six tissues. Metal concentration levels in chicken tissues ranged from 0.02 μg/g to 31 μg/g in muscle, 0.12 μg/g to 452 μg/g in liver, 0.03 μg/g to 505 μg/g in lung, 0.07 μg/g to 143 μg/g in gizzard, 0.06 μg/g to 2063 μg/g in blood, and 0.17 μg/g to 120 μg/g in feather. Interspecific variations include quail displaying higher levels of most metals than chicken tissues, with three times higher Al, Mn, Fe, Co, and Pb levels than in chicken. Domestic avian egg contents accumulated elevated metal levels than eggshells. This study recorded target hazard quotients (daily intake/reference dose) of below 1 for As, Cd, and Pb for chicken meat consumption seven times a week. Target hazard quotients of below 1 were also observed for people who eat eggs seven times a week. The risk quotient revealed that the intake of heavy metals through eating chicken meat and eggs does not pose any apparent threat to the locals. Heavy metal toxicity and its effects on bird populations were evaluated through egg injection treatments and nutrient treatment with different concentrations of Cd, Pb, Zn, and Ni. The hatchability of treated eggs was reduced significantly compared with the control treatment. A low hatching percentage was observed for eggs treated with Cd. Diets mixed with different metal concentrations significantly affected chick weight gain. In conclusion the findings of this study have shown that domestic birds have different capabilities to accumulate metals in their tissues and eggs. Essential elements occur in high levels compared to the non-essential elements in the tissues of the birds. The domestic birds undertaken in this study were not associated with the increased contents of toxic metals in their muscles and viscera, which could be considered as the safe limits for human consumption.,Ph.D
Pages:	357
Call Number:	QR92.M45.A235 2013
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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