Appraisal of Lead in the Organs and Tissues of Domestic Chicken (gallus Gallus Domesticus) in Ibadan

As a result of rapid industrialization and urbanization in developing countries of West Africa, heavy metal pollution is likely to reach disturbing levels. The problem is that preparations are not being made towards the protection of the environment. Nigeria is one of the petroleum exporting countries and use of automobiles by middle and high income groups is rather high. In fact, the growing rate of industrialization is gradually leading to contamination and deterioration of the environment, thus industrialization and heavy metal pollution are positively correlated (Walsh 2000; Olaifa et al. 2004). The Nigerian petroleum contains>0.45 g/l lead as per the Nigerian Industrial Standards (NIS 116:1981). In Nigeria, gasoline with an average lead content of 0.66 g/L remains in use. With high automobile importation, the national consumption of petrol in the country is estimated at 20 million liters per day, with about 150 people/car/city, therefore close to 15,000 kg of lead is emitted into the environment through combustion daily. Heavy metal pollution is posing a serious problem in Nigeria, threatening animals, human health and quality of the environment (Dekofehiniti 2012). Food safety is a major public concern worldwide. The risk of heavy metal contamination in meat is of great concern for both food safety and human health because of the toxic nature of these metals at relatively minute concentrations (Akan et al. 2010). The poultry industry is one of the largest and fastest growing agro based industries in the world. This can be attributed to an increasing demand for poultry meat and egg product (Burel and Valat 2009). Several millions of chickens are raised annually as a source of food for both their meat and eggs. A complete and balanced diet is necessary for human health and vitality. Chicken meat is a major source of protein to man and is widely consumed in Ibadan city and other parts of the world so its safety cannot be ignored. Meat of chicken is rich in many of the essential nutrients including protein (essential amino acids), minerals (e.g., iron, zinc, selenium), vitamins (e.g., Vitamin E) and fat (essential fatty acids such as Omega-3 fatty acids) (Schonfeldt and Gibson 2008). Birds population are particularly susceptible to the effects of anthropogenic activities on the environment. Several biological and physiological processes, such as eating habits, growth, age, breeding, moulting may influence metal concentration and distribution in birds (Kim et al. 2007). The concentration of heavy metals in internal tissues of chicken has been extensively determined by several researchers (Demirbas 1999; Mariam et al. 2004; Iwegbue et al. 2008; Uluozlu et al. 2009). According to Duruibe et al. (2007), some heavy metal ions that are known to be potentially toxic includes aluminium, arsenic, cadmium and lead. Toxic elements can be harmful to birds even at low concentrations when ingested over a long period of time (Young 2005). In recent times, there has been considerable interest in the level of heavy metallic elements in foods because of their deleterious effect on human health (Uche 2012). Apart from those communities exposed to high levels of pollution by industrial effluents or emissions rich in heavy metals, it is evident that, for most individuals food and diet are the most common sources of ABSTRACT