Aidan Doyle’s research while affiliated with Manchester Metropolitan University and other places

Potable water on aircraft is currently monitored for microbiological contaminants of water quality such as E. coli, but because the source water for aircraft is pre-treated water from municipalities, chemical contaminants are not assessed. This neglects the possibility of aircraft pneumatic systems, interconnected with other systems such as the engines and hydraulic oil reservoirs, from becoming fouled and contaminating the potable water onboard with organophosphate esters and other contaminants of concern. In this novel initial qualitative study potable water samples were taken on twenty domestic and international flights on various commercial aircraft. The samples were analyzed with high-resolution liquid chromatography mass spectrometry and compared against 18 Mohm ultrapure water and tap water blanks drawn from departing airports. Suspect compounds were identified using safety data sheets for commonly used aircraft oils and compounds previously identified in aircraft cabin contamination research. Tributyl phosphate, the primary component in aircraft hydraulic oil, was confirmed to be present in the potable water of the majority of flights sampled (11 of 20 flights). Other organophosphates were also identified in the water on a high percentage of flights (tris (chloropropyl) phosphate (TCPP): 20%; triphenyl phosphate (TPhP): 10%; tris (butoxyethyl) phosphate (TBEP): 10%). The qualification of the compounds is supported by mass accuracy, fragment, isotope abundance, and adduct data. This work suggests that as there is currently a potentially unaddressed occupational and public health risk. Detailed quantitative chemical monitoring of aircraft potable water is therefore recommended to fully establish the magnitude of this risk.

Potable water on aircraft is currently monitored for microbiological contaminants of water quality such as E. coli, but because the source water for aircraft is pre-treated water from municipalities, chemical contaminants are not assessed. This neglects the possibility of aircraft pneumatic systems, interconnected with other systems such as the engines and hydraulic oil reservoirs, from becoming fouled and contaminating the potable water onboard with organophosphate esters and other contaminants of concern. In this novel initial qualitative study potable water samples were taken on twenty domestic and international flights on various commercial aircraft. The samples were analyzed with high-resolution liquid chromatography mass spectrometry and compared against 18 Mohm ultrapure water and tap water blanks drawn from departing airports. Suspect compounds were identified using safety data sheets for commonly used aircraft oils and compounds previously identified in aircraft cabin contamination research. Tributyl phosphate, the primary component in aircraft hydraulic oil, was confirmed to be present in the potable water of the majority of flights sampled (11 of 20 flights). Other organophosphates were also identified in the water on a high percentage of flights (tris (chloropropyl) phosphate (TCPP): 20%; triphenyl phosphate (TPhP): 10%; tris (butoxyethyl) phosphate (TBEP): 10%). The qualification of the compounds is supported by mass accuracy, fragment, isotope abundance, and adduct data. This work suggests that as there is currently a potentially unaddressed occupational and public health risk. Detailed quantitative chemical monitoring of aircraft potable water is therefore recommended to fully establish the magnitude of this risk.

Occupational exposure to oil fumes, organophosphates, halogenated flame retardants, and other volatile and semi-volatile contaminants is a concern within the aviation industry. There is no current consensus on the risk attributed to exposure to these chemical classes within the aircraft cabin. Contaminant concentrations rarely exceed conventional air quality guidelines, but concerns have been raised about these guidelines' applicability within the aircraft environment. This systematic review, the largest and most comprehensive completed to date on the subject matter, aims to synthesize the existing research related to chemical and other exposures inside the aircraft cabin to determine the occupational risk that may be attributed said exposure, as well as, determine knowledge gaps in source, pathway, and receptor that may exist. The Science Direct, Scopus, and Web of Science databases were queried with five search terms generating 138 manuscripts that met acceptance criteria and screening.. Several potential areas requiring future examination were identified: Potable water on aircraft should be examined as a potential source of pollutant exposure, as should air conditioning expansion turbines. Historical exposure should also be more fully explored, and non-targeted analysis could provide valuable information to comprehend the aircraft cabin exposome. Occupational risk under typical flight scenarios appears to be limited for most healthy individuals. Contaminants of concern were demonstrated to be extant within the cabin, however the concentrations under normal circumstances do not appear to be individually responsible for the symptomologies that are present in impacted individuals. Questions remain regarding those that are more vulnerable or susceptible to exposure. Additionally, establishing the effects of chronic low dose exposure and exposure to contaminant mixtures has not been satisfied. The risk of acute exposure in mitigable fume events is substantial, and technological solutions or the replacement of compounds of concern for safer alternatives should be a priority.