Volatile Organic Compounds Produced During Irradiation of Mail

Abstract

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.

Unknown Exposures: Gaps in Basic Characterization Addressed with Person-Portable Gas Chromatography-Mass Spectrometry Instrumentation

“…Widespread use of SPME in numerous fields has occurred since the method was first introduced in 1990, (11) including forensics, (12,13) biomedical applications, (14) environmental sampling, (15,16) historical document preservation, (17) sampling for worker health protection to determine unknown process reaction byproducts, (4) and for rapid sampling of chemical warfare agent compounds with relative safety. (18,19) …”

“…Incomplete or inaccurate ingredient lists (1,2) and the presence of unanticipated chemical reaction products (3,4) will potentially lead to inadequate exposure assessments unless work is performed to determine the actual chemicals present. A study completed within the past 10 years found several examples where disclosure of chemical constituents in three commercial products was legally required, but the respective material safety data sheet (MSDS) data did not list the correct hazardous ingredients.…”