Ng Sai Leung, Chan Lung Sang, Lam Kin Che, Chan Wing Kan
Department of Geography and Resource Management, The Chinese University of Hong Kong, Shatin, NT, Hong Kong.
Environ Monit Assess. 2003 Dec;89(3):221-32. doi: 10.1023/a:1026103318778.
This study examined the levels of seven heavy metals (namely zinc, copper, cadmium, chromium, lead, manganese and iron) and their associations with magnetic properties in playground dust of Hong Kong. Results showed that the playground dust contained high concentrations of Zn (mean = 1883 microg g(-1)), Cu (mean = 143 microg g(-1)) and Cr (mean = 263 microg g(-1)). Qualitative examination of dust samples under microscope indicated local traffic as one of the important pollutant sources. Magnetic measurements indicated that these anthropogenic pollutants mainly consisted of coarse-grained multidomain (MD) ferrimagnetic minerals. Superparamagnetic (SP), stable single domain (SSD) ferrimagnetic grains and non-ferrimagnetic minerals were present in relatively small amounts. Significant correlations between heavy metals and various magnetic parameters indicated a strong affinity of heavy metals to magnetic minerals hence pointed out the potential of magnetic properties for simple and rapid proxy indications of heavy metal pollution in playground dust.
本研究检测了香港操场灰尘中七种重金属（即锌、铜、镉、铬、铅、锰和铁）的含量及其与磁性的关联。结果表明，操场灰尘中锌（均值 = 1883微克/克）、铜（均值 = 143微克/克）和铬（均值 = 263微克/克）的浓度较高。显微镜下对灰尘样本的定性检查表明，本地交通是重要的污染源之一。磁性测量表明，这些人为污染物主要由粗粒多畴（MD）亚铁磁性矿物组成。超顺磁性（SP）、稳定单畴（SSD）亚铁磁性颗粒和非亚铁磁性矿物的含量相对较少。重金属与各种磁性参数之间的显著相关性表明重金属与磁性矿物具有很强的亲和力，因此指出了利用磁性特性简单快速地指示操场灰尘中重金属污染的潜力。
