British Airways flight diverted to YVR after passengers suffer smoke inhalation

[Ian W]

Originally Posted by MrsDoubtfire

Carbon monoxide and/or hypoxia for example can cause confusion and other described symptoms:
https://www.cigna.com/healthwellness...lertness-confu
https://cfpub2.epa.gov/ncea/risk/rec...TOKEN=19447862

The health effects associated with exposure to CO range from the more subtle cardiovascular and neuro-behavioral effects at low concentrations

After landing some passengers spoke about CO:
“It was pretty scary,” he said, adding they were told there were some technical problems with the plane. “The cabin crew on the top deck weren’t feeling very good because it was something to do with some carbon monoxide or something, that’s what [the firefighters] were talking about,” he said.
British Airways flight forced to land in Vancouver after crew members fall ill | Globalnews.ca

The cabin crew all happily deplaned and walked into the hospital so it is unlikely that Carbon Monoxide was to blame as recovery from that takes some time as the haemoglobin has been bound with the carbon monoxide into carboxyheamoglobin which will take nearly an hour of 100% oxygen or ~6 hours with normal air to recover from.

Even Carbon Dioxide at high concentrations can give similar symptoms to those noted at high concentrations known as hypercapnia - perhaps a leaking CO2 bottle?

Symptoms and signs of early hypercapnia include flushed skin, full pulse, tachypnea, dyspnea, extrasystoles, muscle twitches, hand flaps, reduced neural activity, and possibly a raised blood pressure. According to other sources, symptoms of mild hypercapnia might include headache, confusion and lethargy. Hypercapnia can induce increased cardiac output, an elevation in arterial blood pressure, and a propensity toward arrhythmias.[4][5] In severe hypercapnia (generally PaCO2 greater than 10 kPa or 75 mmHg), symptomatology progresses to disorientation, panic, hyperventilation, convulsions, unconsciousness, and eventually death.
https://en.wikipedia.org/wiki/Hypercapnia