Trycresyl phosphate is neurotoxin. It wouldn't cause blood oxygen saturation to drop.
Carbon monoxide could do that (and tunnel vision) but I couldn't google up any reports of it being a known issue on jets (lots on GA/prop). However it seems some are concerned about CO...
http://www.holidaytravelwatch.net/wp...in-the-air.pdf
The AAIB did not dismiss the notion that the crew and passengers of the Birmingham flight were not exposed to CO (they could not find CO at any appreciable level), but did concede that exposure to neurotoxins or CO could produce the same symptoms.
In 2002, a Professor Nazaroff testified before the US House of Representatives, concluding that “During abnormal operating conditions, exposure to engine oils, hydraulic fluids, and their degradation products (such as CO and Formaldehyde) might occur. No data have definitely linked exposure to these compounds with reported effects in cabin occupants”.
He also called for CO monitors to be placed in cabins and for an enquiry into the ‘toxicity’ of the constituents of the oils or their ‘degradation products’.
The few papers I found on cabin air quality all seem to report CO within FAA limits.
Do you have CO monitors? Credit card size CO detectors are available on places like ebay.