Mentions: Perchlorate inhibits uptake of iodide into the thyroid glandleading to irregular production of thyroid hormone and giving rise todevelopmental problems, neurological disorders, reduced intelligence, andcerebral palsy. Human exposure to perchlorate has not been quantified, andcurrent environmental exposures are unknown. Perchlorate is wide spread as aresult of both natural and anthropogenic sources, and has been detected indrinking water, food, and both human and cow milk. Sensitive and selectivemethods for in-field monitoring would aid in mitigating exposure as well astracing remediation efforts. Currently, the EPA has set reporting limits at 4 ppb. The most common methods for perchlorate detection are ion chromatographycoupled to conductivity detection, and liquid chromatography coupled to massspectrometry. While these methods are very capable, their size, complexity, andcost limit the use to well-equipped and well-funded laboratories. Inexpensiveand compact analyzers are needed that are capable of field measurements. Herewe present a simple, rapid, and inexpensive system for monitoring perchloratelevels in water samples using microchip capillary electrophoresis withconductivity detection. Microchip devices enjoy low-cost fabrication andinstrumentation as well as portability. Sub-ppb detection limits will be shownas well as separation of perchlorate from other water contaminants. Furthermore,separation occurs in 65 seconds, providing near real-time perchloratemeasurements. Samples can be run without pretreatment, aside from filtrationfor turbid waters. In-field monitoring systems will also be presented that arecapable of drawing samples directly from the surface water and analyzing them onsite (see Figure 2).
Affiliation: P S Analytical, Arthur House, Crayfields Industrial Estate, Main Road, Orpington, Kent BR5 3Hp, UK.
No MeSH data available.