Some reactive volatile organic compounds (VOCs) are prone to degradation during sampling in an ozone-rich environment. A wide variety of different chemicals have been used to remove the ozone prior to sampling, but the possibility of interference by such chemicals with the sampled VOCs has not been thoroughly examined. In the present investigation, the retention/degradation of four terpenes (α-pinene, β-pinene, 3-carene, and limonene) and isoprene together with some of their oxidation products (α-pinene oxide, nopinone, 4-acetyl-1 -methylcyclohexene (AMCH), methylglyoxal, and methacrolein) has been studied, using various ozone-removing chemicals in an attempt to evaluate their potential as ozone scrubbers in the sampling of ambient air. The chemicals included in this first screening and their ozone-removing capacity are as follows: KI, MnO{sub}2, and Na{sub}2SO{sub}3 removed ozone for more than 24 h when exposed to 73-78 ppb (150-160 μg/m{sup}3) at a sampling flow rate of 500 mL/min. Silanized poly(1,4-phenylene sulfide) (PFS) removed ozone for 5 h, unsilanized PFS removed ozone for 1 h and 50 mm, and Na{sub}2S{sub}2O{sub}3 removed ozone for 20 mm. The recovery of the selected compounds with the different scrubbers was >95 for all compounds for KI; >95 for the terpenes oxidation products; >90 for the terpenes and isoprene for PFS; >90 for the terpenes and isoprene for MnO{sub}2 on copper nets, Na{sub}2SO{sub}3, and Na{sub}2S{sub}2O{sub}3; and <90 for the terpenes and isoprene for carulite (a commercial mixture between MnO{sub}2, CuO, and Al{sub}2O{sub}3), CuO, and indigo carmine.
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