Methods for the characterization of Jet Propellent‐8: vapor and aerosol

Abstract

Jet Propellant-8 (JP-8) has been responsible for the majority of reported chemical exposures by the US Department of Defense. Concerns related to human exposure to JP-8 are relatively new; therefore, there is a lack of literature data. Additionally, health effects related to the composition of the exposure have only recently been considered. Two major questions exist: (1) what is the compositional difference between the aerosol and vapor portions of JP-8 under controlled conditions and (2) what is the most representative method to sample JP-8 aerosol and vapor? Thirty-seven standards, representing more than 40% of the mass of JP-8, were used for characterization of the neat fuel, vapor and aerosol portions. JP-8 vapor samples at a concentration of 1600 mg/m(3) were prepared in Tedlar bags. A portion of the vapor samples was adsorbed on charcoal, Tenax and custom mixed phase sorbents. These samples were then extracted using organic solvent and analyzed using gas chromatography/mass spectrometry. The vapor samples extracted from the sorbent tubes were directly compared with a vapor bag. The samples collected using Tenax sorbent tubes were found to be most representative of the composition of the vapor bags. In another set of experiments, aerosolized JP-8 was generated using a collision nebulizer. Aerosol samples were collected and the chemical composition was characterized. The entire aerosol distribution was collected on a glass filter, extracted into solvent, and analyzed by GC-MS. Finally, the composition of the vapor and aerosol was compared. The vapor was found to represent the lower molecular weight components of JP-8, while the aerosol was composed of higher molecular weight components. Therefore, the vapor and aerosol should be treated as two discrete forms of exposure to JP-8.

Computational Study on the Unimolecular Decomposition of JP-8 Jet Fuel Surrogates III: Butylbenzene Isomers (n-, s-, and t-C14H10)

“…Among C−H bond cleavages, the most favorable one occurs from the α carbon in the side chain producing 1-phenyl-but-1yl with an energy loss of 369 kJ mol −1 . The other H losses from sp 3 carbon atoms require higher energies of 411, 408, and 420 kJ mol −1 and forming the corresponding 2-yl, 3-yl, and 4-yl 1phenyl-butyl radicals, respectively. We do not consider here the ruptures of C−H bonds on the sp 2 carbons of the aromatic ring, which are unlikely to compete because their bond energies are typically much higher, e.g., 466 kJ mol −1 for benzene.…”

Distillates (petroleum), hydrotreated light [MAK Value Documentation, 2016]

“…Jet fuel JP-8 contains more shorter-chain hydrocarbons in the vapour phase and more longer-chain hydrocarbons in the aerosol phase, but the fraction of C13-C17 compounds in the aerosol is at the most twice as high as in the liquid. The limit of depletion/accumulation is about C12 (JP-8; Gregg et al 2007). The concentration is determined based on the sum of the CH compounds from C9 to C16; the vapour saturation concentration of n-C14 is only 15 ml/m 3 and the vapour saturation concentrations of n-C15 and n-C16 are even lower.…”

A review of analytical methods for the identification and quantification of hydrocarbons found in jet propellant 8 and related petroleum based fuels

“…In another study, 37 compounds were identified from JP-8 neat fuel, vapor and aerosol (Gregg et al, 2006). These compounds were identified using retention time matches with authentic standards and by comparison to EI mass spectra from databases.…”