EPA Method 8330 is used to measure explosives residues in water and soil samples, using HPLC with UV detection.¹ Target analytes are nitroaromatic and nitramine explosives and their degradation products. Obtaining pure, neat compounds for these standards can be very difficult. Some of these commercial-grade materials contain desensitizing agents such as beeswax, water, or other manufacturing by-products. Many are shipped wet and must be carefully dried before preparation.
To ensure the highest quality standards, Restek chemists carefully purify or synthesize all of the compounds listed in EPA Method 8330. All compounds are 98% pure or higher. Multiple analytical techniques including GC, HPLC, GC/MS, and DSC are used to verify raw material purity.

Reference
¹US Environmental Protection Agency. Test Methods for Evaluating Solid Waste, Physical/Chemical Methods. SW-846 Update III, Office of Solid Waste, Washington, DC, 1997.
(Reference not available from Restek.)