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Abstract.-The so-called "Oddy test" has gained popularity in art and archaeology collections because it is inexpensive to use, and the results are relatively easy to analyze. However, the method is also subjective and does not identify the pollutants. Here we present a modification to the traditional test that addresses these drawbacks and aims at providing solutions. Activated carbon was used to adsorb the volatile emissions generated within the standard Oddy test setup. Gas chromatographymass spectrometry (GC-MS) analysis of the volatile organic compounds (VOCs) desorbed from the activated carbon detected pollutants within a considerably shorter time frame than the traditional Oddy test and provided both qualitative and quantitative data. GC-MS analysis of volatiles offgassed during the Oddy test provided information about the VOCs from local brands of materials commonly used for conservation and storage of objects in collections. The use of GC-MS analysis of volatiles improves the Oddy test in a fast, sensitive, and quantitative manner.

Nitroguanidine, a widely used nitramine explosive, is an environmental contaminant that is refractory, persistent, highly mobile in soils and aquifers, and yet under-researched. Nitroguanidine determination in water and soil poses an analytical challenge due its high hydrophilicity, low volatility, charge neutrality over a wide pH range, and low proton affinity which results in low electrospray interface (ESI)-MS sensitivity. A sensitive method for the determination of nitroguanidine in aqueous and soil matrices was developed. The method is based on reduction by zinc in acidic solution, hydrophobization by derivatization, preconcentration on C18 cartridge, and LC-MS quantification. The demonstrated limit of detection (LOD) reaches 5 ng/L and 22 ng/g in water and soil, respectively. Analysis of a contaminated site demonstrates that it is possible to map a contamination plume that extends over 1 km from the source of the contamination.