1. DIRECT DETERMINATION OF PERCHLORATE IN DRINKING WATER BY ION CHROMATOGRAPHY
Mehmet Fatih CENGIZ, Ayşe Kevser BİLGİN Akdeniz University, Faculty of Engineering, Food Engineering Department, Antalya/TURKEY
ABSTRACT : Perchlorates, which are commonly used in fertilizers and fireworks, rockets and other explosives as solid oxidizer; reduce the synthesis of thyroid hormones by preventing the transportation of iodine through the thyroid gland and thus cause to permanent health problems especially in woman and infants. The main exposure to the perchlorates takes place due to pollution of ground and surface water via to contamination from the agricultural areas and industrial wastes.In this work, a sensitive Ion Chromatography(IC) method was proposed for the determination of perchlorate in drinking water samples. The method entails measurement of conductivity, filtration through 0,45 ìm syringe filter and injection. No sample pretreatment and concentration steps were required prior to the injection. Perchloratewas separated by anion-exchange chromatography and detected by conductivity detector. The calibration curve was linear in the concentration range comprised between in the range of 10 ìg/Land 200 ìg/Lperchlorate(R2 = 0,998). The limit of detection (LOD) and limit of quantification (LOQ) were estimated to be 2,41 µg/L and 8,04 µg/L , respectively. The recovery values of drinking water was 97,74 % ± 0,72. Six different tap water samples were analyzed with the improved technique. No perchlorateresidues (>LOD) were found to be in the analyzed water samples. Compared to other reported methods for perchlorate, the developed IC method is sensitive and simple as well as does not require any chemical derivatization and sample pre-concentration. Therefore this method could be suggested as an alternative analytical metod for routine laboratory testing.
Analytical conditions
System
Dionex ICS-5000 Ion chromatography system
Column
IonPac™ AS19 (250 mm × 2 mm i.d.)
Guard column
IonPac™ AG19 (50 mm × 2 mm i.d.)
Flow rate
1 mL/min
Mobil Phase
10 mM NaOH
Detection
Conductivity detector
Column Temperature
30 ºC
Detector Temperature
Injection Volume
125 μL, full loop injection
System back pressure
~1800 psi
Total run time
30 min
INTRODUCTION: Perchlorate is a well-known environmental contaminant. Pregnant and nursing women, fetus, infant and young children, individuals with hypothyroidism are sensitive groups for the exposure of trace level of perchlorate. Perchlorate is a compound containing one chlorine atom and four oxygen atoms (Kirk vd.,2003) .
Although there has been various technique such as spectrophotometric, chromatographic and colorimetric for the determination of perchlorate, it has commonly been determined using ion chromatography (IC) with suppressed conductivity detection
Anthropogenic Sources of Perchlorate
Rocket Fuel
Fireworks
High explosives
Flares
Herbicides
Automobile airbags
Tracer munitions
Detergents (Soldin vd.,2001).
Method performance
Linearite
10 µg/L µg/L (R2 = 0,998).
Calibration equation
y = 1174 x – 0.647
Limit of detection (LOD)
2,41 µg/L
Limit of quantification (LOQ)
8,04 µg/L,
Recovery
97,74 % ± 0,72.
Repeatability (RSD)
4,24
Table 1. Perchlorate Concentration Of Water in Different Regions
Area
Sample
Perchlorate level
References
California
tap water
<4-29 μg/l
Anonymous,2011
India
ground-water
0,02-0,74 µg/l
Anonymous,2012
China
drinking water
˂ ,4 µg/l
Wu vd.,2010
Califonia
well water
µg/l
Motzer vd. , 2001
Middle Rio Grande Basin
0,12-1,8 µg/l
Plummer vd.,2006
California ve ABD (Southwest)
> 0,1 µg/l
Fram vd.,2011
California(Northeast coast)
˂1 µg/l
Fram vd. ,2011
Turkey (Hatay region)
irrigation water
0,59 µg/l
Sungur vd.,2010
0,44 µg/l
REFERENCES :
ANONYMOUS 2013A,
ANONYMOUS, 2013B,
Anonymous, 2011, U.S. Department Of Health And Human Services Public Health Service., Toxicological profile for perchlorates. Agency For Toxic Substances and Disease Registry, Atlanta, Goergia,(2011).
Anonymous, 2012, California Department Of Public Health, Perchlorate in California drinking water: monitoring update for active and standby sources. perchl/monitoringupdate.htm,(2012).
BOLDYREV, V.V., Thermal decomposition of ammonium perchlorate. Thermochimica Acta 443(1), 1-36 ,(2006).
EPA Basic Information about P in Drinking Water,
FRAM, M. S., Belitz, K., Probability of detecting perchlorate under natural conditions in deep groundwater in California and the Southwestern United States. Environmental Science Technology 45 , Pp:1271–1277,(2011).
GREER, M. A., Goodman, G., Pleus, R. C., and Greer, S. E., Health effects assessment for environmental perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in humans. Environ Health Perspect 110. Pp:927-37,(2002).
KIRK, A.B., Smith, E.E., Tian, K., Anderson, T., Dasgupta, P.K., Perchlorate in milk. Enviromental Science Technology 37, Pp: 4979–4981,(2003).
MOTZER, W. E., Perchlorate: problems, detection, and solutions. Environmental Forensics 2, Pp: 301–311,(2001).
PARKER, D.R., Seyfferth, A. L., Reese, B. K., Perchlorate in groundwater: a synoptic survey of “Pristine” sites in the coterminous United States. Environmental Science Technology 42, Pp: 1465–1471,(2008) .
PLUMMER, L.N., Bohlke, J.K, Doughten, M.W., Perchlorate in pleistocene and holocene groundwater in North-Central New Mexico. Environmental Science and Technology 40, Pp: 1757–1763,(2006) .
SOLDIN, O.P., Braverman, L.E., Lamm, S.H., Perchlorate clinical pharmacology and human health: a review. Therapeutic Drug Monitoring 23(4), Pp: ,(2001) .
SUNGUR, Ş., Sangün, M.K., Ion chromatographic determination of perchlorate in foods consumed in Hatay region. Food Chemistry 126(1), Pp: , (2010) .
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WU, Q., Zhang, T., Sun, H.W., Kannan, K., Perchlorate in tap water, groundwater, surface waters, and bottled water from China and its association with other inorganic anions and with disinfection byproducts. Archives of Environmental Contamination and Toxicologyl 58, Pp: 543–550,(2010) .
Real samples:
In order to evaluate the effectiveness of this method for the determination of glyphosate, the collected tap water (n=6) samples were analysed. There were no glyphosate residues in the tested water samples.