Permissible Exposure Levels for Selected Military Fuel Vapors (1996) / Chapter Skim
Currently Skimming:
7 Effects of Military Fuel Vapors on the Central Nervous System
7 Effects of Military Fuel Vapors on the Central Nervous System
Pages 56-68
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 56... ...
The achievable depth of anesthesia and the rate at which anesthesia occurs are relater! to the minimum alveolar concentration (MAC)
|
From page 57... ...
These values have not been reported for JP-5, JP-S, and DFM. NEUROPHYSIOLOGICAL ED PSYCHOLOGICAL EFFECTS OF FUEL VAPORS Many organic solvents, including those that are components of military fuels, have the potential to cause narcosis and death after acute exposure.
|
From page 58... ...
Data on the effects of chronic exposure to jet fuels are sparse. Knave and co-workers reported on two groups of aircraft factory workers exposed to jet fuels (ICnave et al., 1976a,b, 1978, 1979; Struwe et al., 1983~.
|
From page 59... ...
had exposure described as "continuous exposure for several hours daily to high concentrations of jet fuel fumes in the fuel rig or the test cells or intermittent exposure to high concentrations for at {east 20-30 min each time with an average frequency of at least every second or third week." Exposure of the less heavily exposed group (group B) was characterized as "less frequent intermittent exposure that group A." A multicomponent evaluation of neurological and psychiatric factors was made.
|
From page 60... ...
Based on the results from the reference groups, the authors concluded that the jet-fuel-exposed workers exhibited higher prevalence of those symptoms and signs than expected. Knave and co-workers noted the need for further blind controlled studies of workers chronically exposed to jet fuels.
|
From page 61... ...
m3 for engine testers, and IS5-248 mg/m3 for mechanics. Exposed and control subjects were evaluated via medical history, stanciardizecT interview for neurasthenic symptoms, clinical neurological examination, psychiatric interviews and ratings, psychological tests, and neurophysiological examinations including EEGs, nerve conduction velocities, and vibration sensation thresholds.
|
From page 62... ...
In contrast to the psychiatric findings, the neurophysiological measurements indicated that nearly all subjects were clinically normal and provident only suggestive evidence of polyneuropathy. These neurophysiological measurements were technically crude and would not meet currently accepted methods for defining polyneuropathy and peripheral neuropathy (e.g., see Sweeney et al., 1993~.
|
From page 63... ...
groups in the results of psychological tests that focus on attention and sensorimotor speed. Two psychomotor tests administered in the study evaluated reaction time.
|
From page 64... ...
for consideration as confounders, interferences with testing, or modifiers of the effects of solvents included age, gentler, ethnicity, previous head trauma, hobby exposures, alcohol consumption, drug use, genetic factors, exposure to other chemicals, and preexisting diseases or conditions. The ICW concluded that the validity, reliability, sensitivity, specificity, and predictive value of various neurological and psychological tests needed to be established as a basis for screening exposed workers for neurotoxic effects.
|
From page 65... ...
Therefore, the minimum alveolar concentrations (MACs) for the volatile components of military fuels may be used to help establish STELs.
|
From page 66... ...
Thus, in establishing the STEL for vapors having a high partition coefficient, application of a 10-fold safety factor might be appropriate, whereas a 50-fold safety factor might be more appropriate for vapors displaying a Tow partition coefficient because of the rapid onset of anesthesia. CONCI~USIONS jl In one epidemiological investigation, 30 workers exposed to ~et fuel at a Swedish jet-motor factory for an average of ~ 7 years
|
From page 67... ...
67 Cat Cat to ·$ V)
|
From page 68... ...
The neurophysiological examination with electroencephalograms showed greater incidence of abnormalities in jet-fuel exposed workers than in nonexposed woricers. However, the findings of CNS effects attributable to long-term exposure were considered questionable for a number of reasons, including weak and inconsistent evidence of impairment, inadequate methods of evaluation, inadequate consideration of confounding factors, a small cohort of workers, and a lack of quantitative information on exposure.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.