矿区植物重金属元素测定的两种前处理方法比较

Comparison of Two Sample Pretreatment Methods for the Determination of Heavy Metals in Mineland Plants

分别采用酸消解法和干灰化法处理16种矿区植物,并用原子吸收分光光度法测定其中的Mn、Cd、Cr和Zn的含量。结果表明:除Cd外,两种处理方法对Mn、Cr、Zn的测定结果有明显影响。测定植物组织Cd时,两种处理方法都可采用;测定Mn、Cr元素,采用酸消解法较为合适;测定Zn则宜采用干灰化法,并可适当延长木质部分(根、茎)的灰化时间。

Sixteen plant species from Mn minelands were determined with FAAS for Mn, Cd, Cr and Zn concentrations using acid digestion and dry ashing, respectively. Results showed that the two pretreatment methods had a significant impact on the metal levels except for Cd. For the determination of Cd, either of the two sample pretreatments could be employed. For Mn and Cr, acid digestion was preferable to dry ashing. However, for Zn, dry ashing method was better and for the ashing of woody tissues （root and stem）, longer time might be needed for a complete ashing of sample materials.