Toxic (lead, cadmium and mercury) and essential trace (copper and zinc) metals were measured in muscle, liver and kidney samples of bovine and their relationships with heavy metal concentrations in consumed feed were studied. A total of 216 tissue samples from 72 cows and 216 feed samples from 18 farms were collected during four seasons and analyzed for heavy metals by inductively coupled plasma-optical emission spectrometry after wet digestion. The arithmetic mean concentrations (mg/Kg wet weight) of lead (Pb), cadmium (Cd) and mercury were respectively, 0.221, 0.028 and 0.003 in muscle, 0.273, 0.047 and 0.002 in liver and 0.244, 0.114 and 0.003 in kidney. All measured concentrations (with the exception of Pb in muscle) were below the European Union maximum residual limits (MRL). The Cd contents of the kidney were significantly higher than which observed in other tissues. Although, copper (Cu) and zinc (Zn) levels in all of samples were below MRL, but results showed that many cattles may be suffering from Cu and/or Zn deficiency. Significant and positive correlations between Pb (p < 0.05, r = 0.163) and Cd (p < 0.01, r = 0.303) concentrations in feed and studied organs were observed. As a considerable amount of metals above MRL were noticed in our study, continuous monitoring of these metals is recommended to avoid hazardous transfer to human through the food of animal origin.

在牛的肌肉，肝脏和肾脏样品中测量了有毒（铅，镉和汞）和必需痕量（铜和锌）金属，并研究了它们与食用饲料中重金属浓度的关系。在四个季节中总共收集了来自72头奶牛的216个组织样本和来自18个农场的216个饲料样本，并在湿消化后通过电感耦合等离子体发射光谱法分析了重金属。铅（Pb），镉（Cd）和汞的算术平均浓度（mg / Kg湿重）分别是，肌肉中0.221、0.028和0.003，肝脏中0.273、0.047和0.002，肾脏中0.244、0.114和0.003。所有测得的浓度（肌肉中的Pb除外）均低于欧盟最大残留限量（MRL）。肾脏中的Cd含量明显高于其他组织中观察到的Cd含量。尽管所有样本中的铜（Cu）和锌（Zn）含量均低于最大残留限量（MRL），但结果表明许多牛可能患有铜和/或锌缺乏症。观察到饲料和研究器官中的Pb（p <0.05，r = 0.163）和Cd（p <0.01，r = 0.303）浓度之间存在显着正相关。由于在我们的研究中发现了超过MRL的大量金属，因此建议对这些金属进行连续监测，以避免通过动物源性食品向人类有害转移。观察到饲料和研究器官中的Cd（0.05，r = 0.163）和Cd（p <0.01，r = 0.303）浓度。由于在我们的研究中发现了超过MRL的大量金属，因此建议对这些金属进行连续监测，以避免通过动物源性食品向人类有害转移。观察到饲料和研究器官中的Cd（0.05，r = 0.163）和Cd（p <0.01，r = 0.303）浓度。由于在我们的研究中发现了超过MRL的大量金属，因此建议对这些金属进行连续监测，以避免通过动物源性食品向人类有害转移。