A coroner based in Bournemouth, UK, will begin the examination this week of the cause of death of a British Airways pilot, Richard Westgate, who died in December 2012 aged 43.

Westgate had been undergoing remedial care by a specialist aeromedical clinic in the Netherlands, and he was being treated for symptoms that were believed to the effects of airborne neurotoxins that he encountered when working as a pilot. Tissue samples from Westgate sent for analysis at American medical laboratories, which have reported evidence of neurological damage consistent with exposure to organophosphate substances. It will be the coroner’s task to determine whether this is so, and whether this exposure was the cause of death or a “facilitator” of death. If it were to be found causal, the coroner can rule on measures to prevent future such deaths.

The case the coroner is hearing is highly significant, because the medical effect of the presence of engine oil-derived organophosphate neurotoxins in aircraft cabin air has been in dispute for many years. The official opinion at airline, aircraft manufacturer and Department for Transport level has been that a causal relationship between flightcrew symptoms of illness and the airborne fumes has not been proven. The “fume events” that can occur in aircraft cockpits and cabins happen when hot “bleed air” from the engine compressors - used to provide air conditioning and pressurisation for the passengers and crew - becomes contaminated when engine oil seals leak. The synthetic engine oils contain organophosphates, and when the oil is heated by compression, they form a potentially neurotoxic vapour. The fume events and their source are not disputed by the authorities, but they allege the concentrations are so small as to be medically insignificant.

Legal teams in several countries, with cases of alleged neurotoxic damage to other pilots and cabin crew pending, will be watching this case with interest. Another shift in the legal ground is that lawyers are bringing cases now alleging corporate failure in the duty of care to employees, rather than alleging a breach of safety regulations or air quality standards. Cases brought on the latter ground have foundered because there are no standards for cabin air, and the burden of proof is with the plaintiff. In duty-of-care cases the burden of proof is reversed, and the airlines have to prove they provided it.

Source: Cirium Dashboard