Ion chromatographic determination of low-level perchlorate in natural waters

Abstract EN

Perchlorate (ClO4 –) is a persistent contaminant of drinking-, surface-, and ground- water, and of soils.

Possible contributors of ClO4 – contamination are the military, the space program, and supporting industries, and fertilizers.

Perchlorate has long been known to have a negative effect on the thyroid gland.

It has been added to the United States Environmental Protection Agency's (EPA) Contaminant Candidate List (CCL) in 1998, so that ClO4 – can be regulated at a concentration safe to humans.

This paper describes the determination of trace level ClO4 – in various matrices utilizing ion chromatographic method.

The method utilizes a Dionex IonPac AS11 column with suppressed conductivity detection, 1500 μl sample loop, and a 100 mM NaOH eluent at a flow rate of 1.0 ml/min.

These parameters allow a method detection limit (MDL) of 0.277 μg/l and a short retention time of ∼ 8 minutes.

A quality control, proficiency testing sample from the EPA and a number of environmental samples from New York State (ground water) and California (ground and surface waters) were analyzed by this technique.

Concentrations measured were in the range of 1.9– 217 μg/l.

No evidence of ClO4 – was found in various commonly used fertilizers