A method was developed for measurement of toluene in blood and breath samples, using Tenax GC columns and a Bendix Flasher (Bendix Corp.) coupled to a flame ionization gas chromatograph. Blood samples were collected from six habitual toluene abusers during a 2-h abstinence period. Blood concentrations were found to range from 9.8 to 31.2 mg/L in samples taken shortly after inhaling. Blood half-lives of toluene were found to be much shorter in the first hour after inhalation (53.5 and 49.3 min) than in the second hour (79.3 and 111.2 min). In one of the subjects, blood:breath ratios were determined and averaged 18.2.

Gases produced during structural fires were studied as to their potential toxicities. Carbon monoxide was the only gas measured in concentrations considered to be lethal within a short period of time. No correlations were found between gases produced and materials burning. However, significant correlations were discovered between gases produced and the physical aspects of the fire (intensity, burning rate, and the like). The organic compounds identified within the gases gave insight as to another potential health hazard not yet considered. These organic compounds are the products of free radical reactions and as free radicals their potential as toxics is enormous.

Four individuals died as the result of a propane explosion. As with many propane explosions, the question was raised as to the adequacy of the product's odorization after the autopsy studies had been conducted. In most cases, this question leads to litigation. Ethyl mercaptan is a widely used odorant for propane and was used in this instance. Three of the four victims had blood available at autopsy for study. Quantitative analyses of the victims' blood, obtained during autopsy, were performed using gas chromatography/mass spectrometry, without subjecting the samples to hydrolysis. These analyses determined the relative amounts of porpane and ethyl mercaptan in the blood to be 90, 63, and 175 mL/m3 headspace, and 0.36, 0.34, and 0.77 µg/L blood, respectively. Since mercaptans have been reported in human blood as products of metabolism, modeling studies were conducted to establish the validity of the autopsy data and to develop an autopsy toxicology protocol for investigating explosion deaths. When subjects were not exposed to an atmosphere containing ethyl mercaptan, dimethylsulfide was the only mercaptan detectable in their blood without severe hydrolysis prior to analysis. Metabolic ethyl mercaptan is sufficiently bound to be undetectable by the methods used without hydrolysis. Human subjects were exposed to a flammable mixture of air and propane odorized with ethyl mercaptan. The analyses of the blood from these subjects produced results which were comparable with those for the explosion victims, establishing that the question of odorant adequacy can be addressed at the autopsy of propane explosion victims. It is extremely important that the pathologist and toxicologist investigating gas explosion deaths recognize the valuable evidence existing in the victim's blood.