北京地区六种主产水果矿质元素含量分析及初步膳食风险评估

采用电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定了北京地区主要生产的6种水果中9种矿质元素含量,并以膳食矿物质推荐摄入量或适宜摄入量(RNI/AI)和可耐受最高摄入量(UL)为评价标准,对不同年龄段人群每日从6种水果中摄入矿质元素的量进行初步的膳食风险评估。结果表明:各元素线性回归方程的相关系数均大于0.9990,其检出限在0.125~125 μg/L之间,加标回收率在81.25%~110.46%之间,相对标准偏差均小于8%,且标准物质大米的测定值在国家参考标准值范围内,表明该方法具有较好的准确度和精密度,适用于水果中矿质元素含量的测定。9种矿质元素的平均含量由高到低依次为:Mg(92.58 mg·kg-1) > Zn(6.03 mg·kg-1) > Fe(4.75 mg·kg-1) > Mn(0.97 mg·kg-1) > Cu(0.61 mg·kg-1) > Cr(49.41 μg·kg-1) > Ni(38.19 μg·kg-1) > Co(4.03 μg·kg-1) > Se(1.47 μg·kg-1),各元素之间差异显著(P<0.05),变异系数范围为51.22%(Cu)~99.58%(Ni)。通过对6种水果中元素含量的水平分析和水果之间的纵向比较,得到9种矿质元素在水果中的含量状况和排序规律,但尚未发现富硒样品。水果中矿质元素满足人体需求的程度随着年龄增长而持续降低。桃、葡萄和梨满足人体每日膳食矿物质摄入需求的程度较高。各类人群从6种水果中摄入矿质元素的量是安全的,Mn和Zn的风险指数高于其它元素,应重点关注。

Mineral Element Contents of Six Dominant Fruits in Beijing and Their Dietary Risk Assessment

The contents of 9 mineral elements in 6 fruits produced in Beijing were detected by ICP-MS. Daily intake assessments of mineral elements from the fruits among different populations were conducted and analyzed using recommended nutrient intake (RNI) or adequate intake (AI) and tolerable upper intake level (UL), respectively. The result indicated that the correlation coefficients of linear regression equations of 9 elements were all above 0.9990, and the detection limits were between 0.125 and 125 μg/L. Besides, the recoveries of standard addition were between 81.25% and 110.46%, the relative standard deviations were all below 8%, and the measured values of national standard reference of rice were within the standard range. Hence this method was suitable for the determination of mineral elements in fruits because of its good precision and accuracy. The average contents of 9 mineral elements were followed by the order of Mg (92.58 mg·kg-1) > Zn (6.03 mg·kg-1) > Fe (4.75 mg·kg1) > Mn (0.97 mg·kg1) > Cu (0.61 mg·kg1) > Cr (49.41 μg·kg1) > Ni (38.19 μg·kg-1) > Co (4.03 μg·kg-1) > Se (1.47 μg·kg-1), elements were significantly different from each other (P<0.05) and the range of coefficient of variation was from 51.22% (Cu) to 99.58% (Ni). Through the analysis and comparison of mineral elements in fruits, the content status and ordering rules were obtained, but selenium-rich sample had not been found. The degrees of mineral elements to meet human needs decreased with age. It was considered that peach, grape and pear met the daily dietary mineral intake requirement of the human to a higher degree. Intake of mineral elements from the above 6 fruits were safe to human health. The risk index of Mn and Zn were higher than other elements and should be paid special attention.