BEWARE SCIENCEY NONSENSE!
Over on the uncanny group a few people advocated the "Carbon Monoxide causes people to see ghosts" thing. I responded, and maybe worth sharing here...
Right, so my expertise is on ghosts not Carbon Monoxide but -- like mould, immense amounts of nonsense is talked on this. Look at the symptoms of Carbon Monoxide poisoning. None of them are going to result in hallucinations of apparitions. I wrote a lengthy piece about nonsense "science" pieces on ghosts and this along with
I. infrasound (actually the standing wave - you will be experiencing infrasound now wherever you are reading this, it's just sound below human hearing)
II. Black mould (did you eat it? Was it a Claviceps family wheat fungi? Then sure you might get ergotism and die) - and
III. Carbon Monoxide poisoning --
That is all frequently put forward by "science" people as "ghosts solved"!
The problem is none of this work as explanations.
Carbon Monoxide can cause confusion, and having it experienced it once at a high level headache, flu like symptoms and dizziness. You need hospital attention and are clearly ill - at a much lower level you see flu like symptoms and fatigue. No ghosts: and as you can't uptake oxygen to your blood properly you will be identifiably unwell after the event. This is a chronic condition, you take time to recover. Ghost sightings are visual hallucinations and acute, one off or short term events. In short - it's nonsense. Sure media scientists put it forward but it is a terrible fit symptom wise.
Black mould is worse. The Americans are obsessed with it and there are huge amounts of stuff on the web devoid of any scientific merit claiming a spot of Stachybotrys chartarum will cause you to die, see ghosts, and become so sick you lie in bed listening to Barry Manilow all day or make your toddler detonate in the night. Most of these articles originate from mould removal experts. 😉
Now the fungi kingdom is pretty vast but as the bloke Danny spoke to about mould suggested most black mould is pretty harmless. (In fact people with asthma exposed to Stachybotrys chartarum one of the most common black moulds did better on average than other asthma sufferers in one Harvard study). There is actually very little evidence that mould negatively impacts many respiratory diseases, which is good news for me looking at my bedroom wall.
There are two unpleasant possibilities though; aspergillus and ergot. The first are spores that are reasonably common- won't make you see ghosts but in certain people who are immuno-suppressed they can form cysts in the lung and result in extended treatment alternating the antibiotics clarythromycin and I forget the other one for secondary infection and the antifungal voriconazole. This is a pretty rare thing though and you certainly don't see ghosts in my experience of this. 😉
Luckily in the many ways I've almost accidentally done myself in I've never suffered from ergot poisoning; I have studied it though. Thing is most cases cause muscle spasms, nausea, vomiting and tachycardia as I recall and unfortunately in some cases confusion, unconsciousness and death. Cases are extremely uncommon and fortunately bread moulds we encounter from forgetting to throw the bread out will not be Claviceps purpurea. Despite rumours you can get high off it you can't it seems; also stories of it causing mass psychosis and being implicated as a cause of Witchcraft trials etc. seem to be Enlightenment era myths. It's bloody dangerous but like White Snakeroot killing settlers in the Midwestern USA after their cows grazed on the plant it’s no longer a common issue with modern industrial practices.
So no, hallucinogenic mould spores and mycotoxins that cause you to see spooks are a fun idea but they don't actually exist to the best of our knowledge.
I could go on about this but I've droned on enough - my point though is simple - all these pop science articles on "Science explains ghosts" are generally absolute claptrap.
Science will one day explain the ghost experience; but that begins with a detailed study of that experience, and we have 150 years of neglected peer reviewed research on this issue now!