Determination of Heavy Metals in Various Tissues of Locally Reared (Baladi) Chicken in Jazan Region of Saudi Arabia: Assessment of Potential Health Risks

Heavy metal toxicity in poultry: a comprehensive review

Arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) have been recognized as most toxic heavy metals that are continuously released into the environment, both from natural sources and from anthropogenic production of fertilizers, industrial activities, and waste disposal. Therefore, As, Cd, Hg, and Pb are found in increasing concentrations in bodies of water, fodder, feed, and in the tissues of livestock, including poultry, in the surroundings of industrial areas, leading to metabolic, structural, and functional abnormalities in various organs in all animals. In poultry, bioaccumulation of As, Pb, Cd, and Hg occurs in many organs (mainly in the kidneys, liver, reproductive organs, and lungs) as a result of continuous exposure to heavy metals. Consumption of Cd lowers the efficiency of feed conversion, egg production, and growth in poultry. Chronic exposure to As, Pb, Cd, and Hg at low doses can change the microscopic structure of tissues (mainly in the brain, liver, kidneys, and reproductive organs) as a result of the increased content of these heavy metals in these tissues. Histopathological changes occurring in the kidneys, liver, and reproductive organs are reflected in their negative impact on enzyme activity and serum biochemical parameters. Metal toxicity is determined by route of exposure, length of exposure, and absorbed dosage, whether chronic and acute. This review presents a discussion of bioaccumulation of As, Cd, Pb, and Hg in poultry and the associated histopathological changes and toxic concentrations in different tissues.

Determination of heavy metals and selenium content in chicken liver at Erbil city, Iraq

Heavy metal contamination of poultry meat is a critical issue for human health due to associated risks of cytotoxicity and systemic pathologies after ingestion of such metals. A total of twenty chicken liver samples were collected from markets of Erbil city and analyzed for ten heavy metals contents by Inductively Coupled Plasma Optical Emission Spectrometry. The targeted metals were cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), mercury (Hg), zinc (Zn) and selenium (Se). The average concentrations (mg/kg) of targeted trace elements were 0.06±0.027, 0.06±0.05, 2.05±0.34, 1.85±0.47, 0.15±0.17, and 33.53±5.24 for Co, Cr, Cu, Mn, Ni, and Zn respectively. Copper (Cu) levels significantly exceeded the maximum permissible limit of WHO. Moreover, the average concentrations of toxic heavy metals and selenium were 0.07±0.037, 0.278±0.10, 0.11±0.083, and 2.01±0.454 mg/kg for Cd, Pb, Hg, and Se respectively. Hg and Pb levels exceeded the permissible limits of WHO. Higher levels of Cu and Hg in poultry may pose a serious threat to consumers which demand countermeasures and precautions to be taken. Iraqi Standards Authority and relevant official institutions are strongly recommended to regulate safe disposal of heavy metal waste in the environment to reduce animal exposure to such metals.

Risk-based exposure assessment for multiple toxic elements encountered by children in school playgrounds and parks in the southwest region of Saudi Arabia

Children are in direct contact with surface soil and may inadvertently ingest and inhale toxic contaminants while playing; hence, special attention should be given to playgrounds regarding toxic contaminants. The concentrations of ten toxic metals were determined in soil samples collected from school playgrounds and children's parks from the southwest region of Saudi Arabia. The soils were moderately alkaline (pH 7.6-8.8), the texture was dominated by sand particles (54-88%), and the organic matter was in the range of 2.06 to 4.82%. Analytical solutions were prepared by microwave-digestion using a HNO₃/H₂O₂ mixture, and the concentrations of toxic elements were measured by inductively coupled plasma mass spectrometry (ICP-MS). Metal concentrations were recorded in the range of 0.014-0.087, 1.14-3.54, 0.85-23.29, 0.77-36.32, 312.6-2065.7, 285.3-822.6, 75.4-240.8, 0.00-53.12, 0.52-6.80, and 1.25-92.12 mg/kg dry soil for Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn, respectively. The levels of heavy metals in the studied playgrounds were below the permissible limits, indicating insignificant influence of anthropogenic activities and can be considered as unpolluted soil. Values of the enrichment coefficient (EC) and contamination factor (CF) were found to be less than one, suggesting that the source of these elements is mainly the local soil, with the exception of Ni and Zn in certain playgrounds (CF > 1), which indicates a possible contamination from external sources. The non-carcinogenic hazard index calculated for all of the metals was below one, indicating that the exposure to heavy metal through playground soil is unlikely to produce any adverse health effect in children playing in the playgrounds.