Waters has a complete LC/MS/MS system to confirm perchlorate in drinking and irrigation water at levels below the US Environmental Protection Agency's (USEPA) official reference dose 0.0007mg/kg/day
Perchlorate interferes with thyroid iodine intake which causes hypothyroidism, a condition affecting the entire body's metabolism.
Waters's method combines a simple chromatographic separation technique using an anion exchange column, ammonium bicarbonate/acetonitrile mobile phase, and MS/MS detection.
From injection to injection, the entire process takes 15 minutes to confirm perchlorate at parts per trillion (ppt) levels.
Due to careless usage and improper disposal, water-soluble perchlorate can migrate through aquifers and surface water, contaminating soil, drinking and irrigation water.
Perchlorate is cumulative so daily consumption of food and water tainted by perchlorate creates in vitro concentrations above safe levels.
"As the toxic effects of perchlorate become better known, the need to confirm its presence at low ppt levels grows," stated James Willis, director of the chemical analysis market development group at Waters.
"Regulatory agencies and laboratories now have a one-step method to confirm the presence of perchlorate at levels lower than what the USEPA mandates," he said.
Perchlorate has been detected in higher-than-expected levels in 35 of the 50 US states.
Just recently, this chemical was discovered in a well that supplies drinking water for a school in the town of Boxford, Massachusetts.
The levels detected were higher than the state's threshold.
Perchlorate is found in fertilisers and in applications such as tanning and leather finishing, rubber manufacturing, paint and enamel production, lubricant oil additives and in solid rocket propellant.
Waters's LC/MS/MS perchlorate method.
Waters chemists have designed a method that combines chromatographic selectivity and mass spectrometry specificity and sensitivity without requiring sample prep.
The method uses Waters IC-Pak anion/HR chemistry, Waters Alliance HPLC and Waters Quattro micro API mass spectrometer.
The anion exchange column separates all the compounds in a water sample.
The ammonium bicarbonate/acetonitrile mobile phase chromatographically positions trace perchlorate levels between macro levels of chloride and sulphate typically found in food and water.
For more information, please refer to the application note, The Determination of Perchlorate in Water Using LC/MS/MS, PN 720000941EN in the company's technical literature library.
This method is the basis of the US Food and Drug Administration CFSAN perchlorate method and was adapted by the National Food Processors Association.
It is also equivalent with USEPA Method 331.
