title: JP-8 jet fuel exposure and divided attention test performance in 1991 Gulf War veterans.
abstract: BACKGROUND
  Previous research indicates that a large cohort of veterans from the 1991 Gulf War report polysymptomatic conditions. These syndromes often involve neurocognitive complaints, fatigue, and musculoskeletal symptoms, thus overlapping with civilian illnesses from low levels of environmental chemicals, chronic fatigue syndrome, and fibromyalgia.
  
  
  METHODS
  To test for time-dependent changes over repeated intermittent exposures, we evaluated objective performance on a computerized visual divided attention test in chronically unhealthy Gulf War veterans (n = 22 ill with low-level chemical intolerance (CI); n = 24 ill without CI), healthy Gulf War veterans (n = 23), and healthy Gulf War era veterans (n = 20). Testing was done before and after each of three weekly, double blind, low-level JP-8 jet fuel or clean air sham exposure laboratory sessions, including acoustic startle stimuli.
  
  
  RESULTS
  Unhealthy veterans receiving jet fuel had faster mean peripheral reaction times over sessions compared with unhealthy veterans receiving sham clean air exposures. Unhealthy Gulf veterans with CI exhibited faster post- vs. pre-session mean central reaction times compared with unhealthy Gulf veterans without CI. Findings were controlled for psychological distress variables.
  
  
  CONCLUSIONS
  These data on unhealthy Gulf veterans show an acceleration of divided attention task performance over the course of repeated low-level JP-8 exposures. The present faster reaction times are consistent with rat neurobehavioral studies on environmental toxicant cross-sensitization and nonlinear dose-response patterns with stimulant drugs, as well as some previous civilian studies using other exposure agents. Together with previous research findings, the data suggest involvement of central nervous system dopaminergic pathways in affected Gulf veterans.
authors.affiliation: Research Service, Southern Arizona VA Health Care System, USA. ibell@u.arizona.edu
authors.forename: Iris R
authors.initials: IR
authors.lastname: Bell
authors.forename: Audrey J
authors.initials: AJ
authors.lastname: Brooks
authors.forename: Carol M
authors.initials: CM
authors.lastname: Baldwin
authors.forename: Mercedes
authors.initials: M
authors.lastname: Fernandez
authors.forename: Aurelio J
authors.initials: AJ
authors.lastname: Figueredo
authors.forename: Mark L
authors.initials: ML
authors.lastname: Witten
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001288:Attention; D016009:Chi-Square Distribution; D004311:Double-Blind Method; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D006838:Hydrocarbons / Q000633:toxicity*; D016014:Linear Models; D008297:Male; D018923:Persian Gulf Syndrome / Q000503:physiopathology*; D011930:Reaction Time; D013997:Time Factors; D014728:Veterans
chemical_list: D006838:Hydrocarbons; C098607:JP8 aviation fuel