LIBS检测土壤污染

Journal of Hazardous Materials 263 (2013) 754–760

Contents lists available at ScienceDirect

Journal of Hazardous

Materials

j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /j h a z m a

t

Rapid detection of soils contaminated with heavy metals and oils by laser induced breakdown spectroscopy (LIBS)

Gibaek Kim a ,Jihyun Kwak a ,Ki-Rak Kim a ,Heesung Lee a ,Kyoung-Woong Kim a ,Hyeon Yang b ,Kihong Park a ,∗

a

School of Environmental Science and Engineering,Gwangju Institute of Science and Technology (GIST),261Cheomdan-Gwagiro,Buk-gu,Gwangju 500-712,Republic of Korea b

Green Institute of Technology Co.Ltd.,B705,Gwangju High-tech Center,313Cheomdan-Gwagiro,Buk-gu,Gwangju 500-470,Republic of Korea

h i g h l i g h t s

•A LIBS method was developed to detect heavy metals and oils in soils.

•Soil samples were collected from abandoned mining areas and military camps.•Clean soils were distinguished from heavy metal-or oil-contaminated soils.•Effects of matrix of soils on the LIBS response were investigated.

•

Pelletizing and sieving of soils were useful to minimize matrix effect.

a r t i c l e

i n f o

Article history:

Received 18June 2013

Received in revised form 14October 2013Accepted 20October 2013

Available online 27 October 2013

Keywords:LIBS

Heavy metals Soils

Chemometrics

a b s t r a c t

A laser induced breakdown spectroscopy (LIBS)coupled with the chemometric method was applied to rapidly discriminate between soils contaminated with heavy metals or oils and clean soils.The effects of the water contents and grain sizes of soil samples on LIBS emissions were also investigated.The LIBS emission lines decreased by 59–75%when the water content increased from 1.2%to 7.8%,and soil samples with a grain size of 75␮m displayed higher LIBS emission lines with lower relative standard deviations than those with a 2mm grain size.The water content was found to have a more pronounced effect on the LIBS emission lines than the grain size.Pelletizing and sieving were conducted for all samples collected from abandoned mining areas and military camp to have similar water contents and grain sizes before being analyzed by the LIBS with the chemometric analysis.The data show that three types of soil samples were clearly discerned by using the first three principal components from the spectral data of soil samples.A blind test was conducted with a 100%correction rate for soil samples contaminated with heavy metals and oil residues.

© 2013 Elsevier B.V. All rights reserved.

1.Introduction

Heavy metals in soils are a concern due to their adverse effects on plants,animals,and human beings [1–5].Heavy metals can accumulate in the environment and be introduced to humans through the food chain [6–9].Heavy metals naturally originate in the Earth’s crust and are introduced to the environment through various anthropogenic sources and/or activities,such as mining,traffic,agriculture,and industrial activities [9,10].Oil contamina-tion in soils can lead to toxic,carcinogenic,and mutagenic effects in humans [11–13].Plant germination and growth can also be inhibited due to the presence of oils in soils [14,15].Oils can be

∗Corresponding author.Tel.:+82627153279;fax:+82627152434.E-mail address:kpark@gist.ac.kr (K.Park).

dispersed into soils by accidental or deliberate oil spillage dur-ing the transportation and/or storage of oil products [16–18].Oil degradation in soils is slow [19,20],and natural degradation relies on temperature,aeration,and light intensity,in addition to other factors [3,21].Natural remediation of oil-contaminated soils could take many years.For instance,it has been reported that the pres-ence of oil in soil can be observed even a few decades or centuries after oil spillage [3,22,23].Thus,the detection of soils that have been contaminated by heavy metals or oils is important for monitoring the exposure to humans and the environment and for establishing effective control strategies.

For the determination of heavy metals in soils,induc-tively coupled plasma-mass spectrometry (ICP-MS),inductively coupled plasma-optical emission spectrometry (ICP-OES),or atomic absorption spectrometry (AAS)can be used,while gas chromatography–mass spectrometry (GC–MS)can be used to

0304-3894/$–see front matter © 2013 Elsevier B.V. All rights reserved./10.1016/j.jhazmat.2013.10.041