Solid phase microextraction with analysis by gas chromatography to determine short term hydrogen cyanide concentrations in a field settingOccupational air concentration ceiling standards should not be exceeded during any part of a working exposure. Air sampling with pumps, and filters or sorbent tubes may be coupled to methods such as gas chromatography for definitive identification of occupational air contaminants. With such methods, 15-minute sample durations are common for ceiling standard comparisons (to trap sufficient analyte for detection) giving a 15-minute time-weighted average, and not an instantaneous concentration. We used 2-minute duration solid phase microextraction (SPME) field sampling, followed later by gas chromatography with a nitrogen-phosphorous detector (GC/ NPD) to detect, identify, and quantify airborne hydrogen cyanide (HCN) concentrations encountered in a field setting. The presence of HCN was confirmed in the atmosphere sampled by SPME field sampling followed by gas chromatography with mass spectrometric detection. The HCN-contaminated atmosphere was from two CS riot control canisters actuated in an enclosed building. With four simultaneous SPME field samples and GC/NPD analysis, the coefficient of variation associated with the HCN peak areas for the samples was 17%, and the HCN concentrations measured ranged from about 12 to 19 ppm. Acetonitrile and acrylonitrile were also detected as volatile nitrogen-containing air contaminants dispersed along with the CS, although their concentrations were not determined.

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High temperatures are frequently used to disperse 2-chlorobenzylidene Ž . malononitrile CS riot control agent. We examined airborne CS degradation products heat-dispersed together with CS from canisters of a type used by law enforcement personnel for crowd and riot control. Air contaminants derived from CS were trapped using a polytetraflouroethylene filter. Analysis was by open tubular gas chromatography coupled to mass spectrometry. Compounds observed in addition to CS included 2-chlorobenzaldehyde, 2-chlorobenzonitrile, quinoline, Ž . 2-chlorobenzylcyanide, 1,2-dicyanobenzene, 3-2-chlorophenyl propynenitrile, cis Ž . and trans isomers of 2-chlorocinnamonitrile, 2,2-dicyano-3-2-chlorophenyl oxirane, 2-chlorodihydrocinnamonitrile, benzylidenemalononitrile, cis and trans isomers of 2-cyanocinnamonitrile, 2-chlorobenzylmalononitrile, 3-quinoline carbonitrile, and 3-isoquinoline carbonitrile.

2-Chlorobenzylidenemalononitrile (CS riot control agent) has been shown to produce a number of thermal degradation products when dispersed at high temperature. We hypothesized that these CS-derived compounds are formed by energy input from heating during the dispersion process. Here we identified organic CS-derived compounds formed from purified CS subjected to temperatures ranging from 300 to 900 degrees C in an inert atmosphere with analysis of tube furnace effluent by gas chromatography and mass spectrometry. We conclude that the production of many CS-derived compounds previously observed during high-temperature dispersion is likely to be heat related.

In 2001, Bacillus anthracis spores were delivered through the United States postal system in a series of bioterrorist acts. Controls proposed for this threat included sanitization with high-energy electrons. Solid phase microextraction was used with gas chromatography/mass spectrometry for field sampling and analysis of volatile compounds apparently produced from polymeric materials such as cellulose and plastics, immediately following processing of mail at a commercial irradiation facility. Solid phase microextraction and direct sampling of air into a cryogenically cooled temperature programmable inlet were used in the laboratory for gas chromatography/mass spectrometry analysis of air in contact with irradiated mail, envelopes only (packaged identically to mail), and air inside irradiated plastic mail packaging bags (with neither mail nor envelopes). Irradiated mail or envelope systems produced hydrocarbons such as propane, butane, pentane, hexane, heptane, methylpentanes, and benzene; and oxygen-containing compounds such as acetaldehyde, acrolein, propionaldehyde, furan, 2-methylfuran, methanol, acetone, 2-butanone, and ethanol. In addition to hydrocarbons, methyl and ethyl nitrate were detected in irradiated bags that contained only air, suggesting reactive nitrogen species formed from air irradiation reacted with hydroxy-containing compounds to give nitro esters. The similarities of volatile compounds in irradiated systems containing paper to those observed by researchers studying cellulose pyrolysis suggests common depolymerization and degradation mechanisms in each case. These similarities should guide additional work to examine irradiated mail for chemical compounds not detectable by methods used here.