【作者】 王慧娟；

【导师】 梁琪；

【作者基本信息】 甘肃农业大学 ， 营养与食品卫生学， 2008， 硕士

【摘要】 本文选取甘南州夏河县藏牦牛放牧牧场中的土壤、牧草和牦牛冷却肉,研究在不同季节、不同采样牧区中样品的农药(有机氯、菊酯类农残)残留污染、重金属污染程度、相互关系,并进行重金属安全风险残留分析,研究结果表明:1.本试验采用单项污染指数法、综合污染指数法对甘南藏牦牛放牧地土壤重金属进行测定,表明各采样点土壤Pb、Hg、Cd重金属含量均未超标,污染水平为清洁,适合生产绿色食品。土壤重金属综合污染程度由大到小顺序依次为2号牧场、1号牧场、3号牧场、4号牧场。2.牦牛放牧地牧草的质量分级采用单项污染指数评定法,1号牧场、2号牧场、3号牧场的Pb、Hg、Cd污染指数在0.5到1.0之间,牧草质量等级为二级,具有轻度污染;4号牧场的Pb、Hg、Cd污染指数小于0.5,牧草质量等级评定为一级,污染水平为清洁,不会对牦牛饲养造成风险性。牧草各采样点重金属综合污染程度由大到小顺序依次2号牧场、1号牧场、3号牧场、4号牧场。3.本试验采用单项污染指数法、综合污染指数法、美国环保局(EPA)重金属污染物对人体安全评价模型,表明牦牛肉受到Pb、Hg、Cd污染程度较轻,不会对暴露人群构成明显危害,属于安全食品。4.试验区各采样点的土壤、牧草和牦牛肉中有机氯、菊酯类农药残留均未检测到。表明夏河县各采样点的土壤、牧草和牦牛肉未被有机氯、菊酯类农药残留污染。5.试验区各采样点可以作为牦牛绿色食品基地,但存在轻度复合污染、增毒效应和潜在风险。因此,必须降低环境中污染物排放总量,减少食物链中污染物迁移量,保障人畜安全和牦牛肉生产加工符合绿色基地标准。更多还原

【Abstract】 This paper studied the heavy metals pollution degree and risk assessment on grazing soil、forage and meat of yak.The result showed:1.This experiment adopted single-pollution index,comprehensive-pollution index and underlying ecology risking assessment model of heavy metals pollution for evaluating grazing soil of yak and showed: heavy metals content of grazing soil had not exceeded standard, pollution level is clean,sampling spots are suitable for producing green food. The order of heavy mental comprehensive pollution degree were:NO.2,NO.1,NO.3,NO.4.2.This experiment adopted single-pollution index for evaluating grazing soil quality of yak and showed:the forage quality of NO.1,NO.2,NO.3 are second grade and had light pollution,the forage quality of NO.4 was one grade and pollution level was clean,which did not produce risk for yak.The order of heavy mental comprehensive pollution degree were: NO.2,NO.1,NO.3,NO.4.3.This experiment adopted single-pollution index,comprehensive-pollution indexand heavy metals pollution risking assessment model(American EPA)for evaluating yak’s meat and showed: yak’s meat were nearly not polluted,and did not produce hazard for exposing consumption body,so it had predominance to produce green food.4. The pesticide residues of organic chlorine and Pyrethroids in the soil, grass and yak meat of Pilot area of the sampling points were not detected. This result showed: the pollution of organic chlorine and Pyrethroids were very slight in the sampling points of soil, grass and yak meat.5.The experimental region had foundmental condition for producing green food of yak,but had slightly compound-pollution,increasing poison effected and potential risked. So it should be done to reduce pollutant discharge,develop touring region conservatively,decrease pollutant transferring context in food chain,which could assure human and animal safe and accord with processing green standard.更多还原