The Journal of Biological Physics and Chemistry



Volume 16, Number 2, pp. 95-102





An estimate of the chronic exposure to neurotoxins of a neurologically injured pilot

Jeremy J. Ramsden

Clore Laboratory, The University of Buckingham, MK18 1EG, England

A recent case study reported on a civil aviation pilot who suddenly died after having been grounded for over a year suffering from serious neurological complaints. Post-mortem investigations revealed extensive neurological damage of the type associated with exposure to organophosphates. The pilot had never suffered an acute exposure incident, hence the need to estimate chronic occupational and nonoccupational exposures. The only significant source of organophosphates in the pilot's life was contamination of aircraft cabin air by the antiwear additives (tricresyl phosphates, TCP) present in jet engine lubricating oil. Exposure to these compounds has been estimated. It is very small compared to the terrestrial workplace exposure limit (for tri-ortho-cresyl phosphate). This finding raises a number of questions requiring further investigation, including: is TCP toxicity enhanced by simultaneous exposure to other neurotoxins found in aircraft cabin air, such as toluene? Is it enhanced by the mildly hypoxic conditions of the aircraft cabin? Could genetic variation render certain individuals much more sensitive to low chronic exposure? Besides, very little is presently known about the effects of ultralong, ultralow exposures typical of the pilot's workplace environment. This also requires further investigation.


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