Acrolein and Acrylonitrile Analysis
Acrolein and Acrylonitrile are listed in EPA methods 603 and 624. The GC/FID method 603 was the recommended method and included specific preservation and hold time information for the analytes. The GC/MS method 624 stated that its compound list could be extended to screen for Acrolein and Acrylonitrile, but that method 603 was the preferred method for those analytes. Since the two methods were published the EPA has published in 40 CFR part 136 the following:
“4 Method 624 may be used for quantitative determination of acrolein and acrylonitrile, provided that the laboratory has documentation to substantiate the ability to detect and quantify these analytes at levels necessary to comply with any associated regulations. In addition, the use of sample introduction techniques other than simple purge-and-trap may be required. QC acceptance criteria from Method 603 should be used when analyzing samples for acrolein and acrylonitrile in the absence of such criteria in Method 624.”
Acrolein is an aquatic herbicide approved for use in California. It has a short half life, and therefore a short hold time of three days from sample collection to analysis unless the sample is preserved by pH adjustment.
Acrolein has preservation criteria unique among the volatile organics analytes, and specifies adjusting the pH to a range of 4-5 to extend the hold time from three to 14 days from sample collection to analysis.
Caltest has specific sample vial sets as well as trained staff to help you with Clean Water Act compliant analyses of Acrolein.
Not many labs are set up to meet the EPA Clean Water Act criteria for analyses of Acrolein. The short hold times and difficult to achieve preservation cause many labs to not include these analytes, or simply not bother to comply with the method criteria.
You may want to perform jar tests to determine how much of what concentration of acid is required to bring the sample into the proper pH. The ratio you use should be such that the acid added does not unduly dilute the sample. Try to keep the amount of acid added to 1 ml or less, if the amount is more than this, note the amount on the chain of custody.