Performance characteristics of selected biodegradable liquid scintillation cocktails

High efficiency, low background, and quench resistance are primary considerations in the selection of a liquid scintillation (LS) cocktail, along with stability of the cocktail with time and reproducibility of the results obtained. These criteria are often compromised to acquire aqueous sample compatibility, or to avoid adverse flammability or toxicity characteristics. Disposability may also affect cocktail selection, since some low level radioactive waste burial sites are refusing to accept toluene- or xylene- based LS wastes, and other solvents are being considered for exclusion. Certain commercially available cocktails purport to circumvent this disposal problem by being drain disposable with local approval. Efficiencies, backgrounds, quench resistance, and sample stability for ten of these cocktails are presented