养殖场饲养鸡对苯并[a]芘的摄入、排泄和积累

在北京市郊区一家中等规模养鸡场采集了不同品种和不同生长阶段的饲养鸡的肌肉和内脏样品,并同步采集了鸡蛋、饲料、粪便和大气样品,测定了其中苯并[a]芘的浓度,据此分析了苯并[a]芘在饲养鸡体内的积累、排泄和代谢的动态过程.结果显示,饲养鸡体内各组织苯并[a]芘的湿重浓度在0.024～0.15ng·g-1之间,肌肉中的浓度显著低于其它组织;饲料和粪便中的浓度显著高于体内各组织浓度.饲养鸡体内摄入的苯并[a]芘约60%在体内代谢,约三分之一直接排泄进入粪便,仅有少量残留在体内如表皮、肌肉和其他器官中.肌肉、肝脏和胃中苯并[a]芘浓度和总累积量的动态变化规律不尽相同.北京居民摄食类似鸡肉导致的对苯并[a]芘的暴露量较春、秋、冬季呼吸暴露量低两个量级,与夏季呼吸暴露量相当.

Intake, Excretion and Accumulation of Benzo[a] pyrene in Chickens from a Chicken Farm in Beijing

Chicken muscle,viscera,egg,feed,dropping and air samples were collected at a medium-size poultry farm in Beijing.The concentrations of benzo[a]pyrene of these samples were measured to address intake,accumulation,excretion,and metabolism of benzo[a]pyrene in chicken.The wet weight concentrations of benzo[a]pyrene in different tissues were from 0.024 to 0.15ng·g-1.The concentration in muscle was significantly lower than those in other tissues while the concentrations in feed and droppings were significantly higher than those in all tissues.Approximately one third of benzo [a]pyrene intake was excreted and around 60% was metabolized.Only a small fraction remained in skin and muscle as residues.Dynamic changes of benzo[a]pyrene concentrations in muscle,liver and stomach showed different patterns.Daily oral intake of benzo [a]pyrene via consumption of similar poultry product in Beijing is approximately two orders of magnitude lower than those of inhalation exposure in spring,fall,and winter,and in the same range of that of inhalation exposure in summer.