Swarup D, Patra R C, Naresh Ram, Kumar Puneet, Shekhar Pallav
Environmental Medicine Laboratory, Division of Medicine, Indian Veterinary Research Institute Izatnagar, 243122, UP India.
Sci Total Environ. 2005 Jul 15;347(1-3):106-10. doi: 10.1016/j.scitotenv.2004.12.055.
Lead is pervasive environmental pollutant with potential public health hazard as a contaminant of food from animal origin. The present study examines the blood and milk lead level in animals reared in areas around different industrial activities and to find out correlation between blood and milk lead levels in lactating cows. Blood and milk samples (n=149) were collected from animals reared around steel processing unit (n=22), lead-zinc smelter (n=21), aluminum processing plant (n=25), rock phosphate mining area cum phosphate fertilizer plant (n=21), coal mining areas (n=46) and closed lead but functional zinc smelter (n=14). Samples were also collected from randomly chosen 52 lactating cows reared in non-polluted areas to serve as controls. Significantly (P<0.05) higher blood lead level was recorded in animals reared around lead-zinc smelting factories followed by closed lead but functional zinc smelter, aluminum processing unit and steel manufacturing plant, as compared to values recorded for control animals. The highest milk lead level (0.84+/-0.11 microg/ml) was detected in animals reared in the vicinity of lead-zinc smelting unit followed by aluminum processing plant and steel processing unit. Analysis of correlation between blood lead levels and lead excretion in milk through sorting the blood lead values into nine different ranges irrespective of site of collection of samples (n=201) revealed significant correlation (r=0.469 at P<0.01) between blood and milk lead concentrations. The lactating cows with blood lead levels above 0.20 microg/ml (Groups 5 to 9) had significantly (P<0.05) higher milk lead excretion than those with blood lead levels from non-detectable to 0.20 microg/ml (Groups 1 to 4). Pearson correlation analysis between blood and milk lead concentrations in 122 animals with blood lead <or=0.20 microg/ml showed non-significant correlation (r=0.030 at P<0.05) but a significant correlation was observed between these two parameters with blood lead level above >0.20 microg/ml indicating that the excretion of lead through milk increases with the increase in blood lead level above 0.20 microg/ml.
铅是一种普遍存在的环境污染物，作为动物源性食品的污染物，具有潜在的公共卫生危害。本研究检测了在不同工业活动区域饲养的动物的血液和牛奶中的铅含量，并找出泌乳奶牛血液和牛奶铅含量之间的相关性。从在钢铁加工厂（n = 22）、铅锌冶炼厂（n = 21）、铝加工厂（n = 25）、磷矿开采区兼磷肥厂（n = 21）、煤矿区（n = 46）和已关闭但仍在运行的锌冶炼厂（n = 14）周边饲养的动物中采集了血液和牛奶样本（n = 149）。还从随机选择的52头在无污染地区饲养的泌乳奶牛中采集了样本作为对照。与对照动物的值相比，在铅锌冶炼厂周边饲养的动物中记录到的血铅水平显著更高（P<0.05），其次是已关闭但仍在运行的锌冶炼厂、铝加工厂和钢铁制造厂周边饲养的动物。在铅锌冶炼厂附近饲养的动物中检测到的牛奶铅含量最高（0.84±0.11微克/毫升），其次是铝加工厂和钢铁加工厂周边饲养的动物。通过将血铅值分为九个不同范围，对样本采集地点不做考虑（n = 201），分析血铅水平与牛奶中铅排泄量之间的相关性，结果显示血液和牛奶中的铅浓度之间存在显著相关性（r = 0.469，P<0.01）。血铅水平高于0.20微克/毫升的泌乳奶牛（第5至9组）的牛奶铅排泄量显著高于血铅水平在未检测到至0.20微克/毫升之间的奶牛（第1至4组）（P<0.05）。对122只血铅≤0.20微克/毫升的动物的血液和牛奶铅浓度进行Pearson相关性分析，结果显示无显著相关性（r = 0.030，P<0.05），但当血铅水平高于0.20微克/毫升时，这两个参数之间存在显著相关性，表明当血铅水平高于0.20微克/毫升时，通过牛奶排泄的铅量会随着血铅水平的升高而增加。
