{"id":410909,"date":"2025-09-09T16:47:11","date_gmt":"2025-09-09T16:47:11","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/410909\/"},"modified":"2025-09-09T16:47:11","modified_gmt":"2025-09-09T16:47:11","slug":"mass-psychogenic-illness-caused-toxic-substance-alert-at-heathrow-says-scientist-heathrow-airport","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/410909\/","title":{"rendered":"\u2018Mass psychogenic illness\u2019 caused toxic substance alert at Heathrow, says scientist | Heathrow airport"},"content":{"rendered":"

Police were called to Heathrow late on Monday<\/a> afternoon when 21 people fell ill in Terminal 4. Initial reports suggested a hazardous material could be involved and part of the airport was evacuated. But when the emergency services conducted a thorough search, no trace of any adverse substance was found.<\/p>\n

A source within the Metropolitan police subsequently suggested the event could be something quite different \u2013 a case of mass hysteria<\/a>. And some experts agree.<\/p>\n

\u201cWhat happened at Heathrow<\/a> is almost certainly an episode of mass psychogenic illness that is anxiety-based,\u201d said Dr Robert Bartholomew, a University of Auckland sociologist who is an expert on the subject.<\/p>\n

While \u201cmass hysteria\u201d might bring to mind medieval reports of dancing plagues and epidemics of \u201cpossession\u201d<\/a>, such events are not unknown in the modern world.<\/p>\n

The term, which has historical stigma and is often erroneously applied to situations from crowd crushes to moral panics, has gone out of use. Such events are now known as \u201cmass psychogenic illness\u201d or \u201cmass sociogenic illness\u201d, which take two main forms \u2013 those that are \u201cmotor-based\u201d and others that are \u201canxiety-based\u201d.<\/p>\n

Among examples of the former was a case in 2011 at LeRoy high school in New York, where affected students displayed vocal and motor tics such as twitches and spasms. While some feared an environmental toxin was at play, experts diagnosed the situation as a case of mass psychogenic illness, aggravated by participation in social or traditional media.<\/a><\/p>\n

\u201cThese outbreaks occur in an atmosphere of anxiety that can span weeks or months. The long-term stress disrupts the nerves and neurons that send messages from the brain,\u201d said Bartholomew, citing a notorious 1692 outbreak in Salem, Massachusetts.<\/p>\n

He said anxiety-based cases were typically triggered by the sudden perception of a toxic agent \u2013 such as an unfamiliar smell. \u201cCommon symptoms include headache, overbreathing, dizziness and fainting,\u201d he said, noting episodes tended to come out of the blue with victims often recovering within minutes.<\/p>\n

It is this type of event that Bartholomew believes occurred at Heathrow. \u201cI always say you have to investigate first before you render the diagnosis of mass psychogenic illness,\u201d he said.<\/p>\n

\u201cBut they have gone there and they\u2019ve tested, and they\u2019ve tested negative. [And there was], rapid onset and recovery, benign, transient symptoms.\u201d<\/p>\n

He added: \u201cI suspect the person taken to hospital may have had a pre-existing condition and it was likely done as a precaution.\u201d<\/p>\n

If the diagnosis of mass psychogenic illness is correct, it would not be the first time an airport has been linked to such an event: Bartholomew investigated a case at Melbourne airport in 2005 when 57 people fell ill after reporting a \u201cgassy smell<\/a>\u201d. Bartholomew <\/a>said a toxic agent could have caused some of the individuals to become unwell but all the signs strongly suggested mass psychogenic illness.<\/p>\n

Such events might not be uncommon. In a 2010 study<\/a>, researchers randomly selected 280 of 747 reports of chemical incidents from the UK\u2019s former health protection agency, finding 19 were probable episodes of mass psychogenic illness. Again, the researchers found odour was a robust predictor of such events, while schools and healthcare facilities were common settings.<\/p>\n

\u201cA substantial minority of chemical incidents may be mass psychogenic illness,\u201d they concluded.<\/p>\n

Prof Sir Simon Wessely of King\u2019s College London, who was part of the team, said it was \u201ca bit early\u201d to come to judgments about the Heathrow event and it was unclear whether there was an unusual odour or what investigations were done to eliminate other causes. But he added: \u201cIf all these come to nothing, then yes, this may be an episode of what we now call mass sociogenic illness.\u201d<\/p>\n

Bartholomew stressed the illness was not a mental disorder and victims were not psychologically disturbed.<\/p>\n

\u201cIt is best described as a collective stress reaction that is based on a belief. We all have beliefs, therefore we are all potential victims,\u201d he said. \u201cIt is not \u2018all in their heads\u2019 in the sense that they are experiencing real symptoms.\u201d<\/p>\n

Wessely added: \u201cStudy after study has never found anything different about those who are affected from those who aren\u2019t. All of us can experience anxiety in certain symptoms, and all of us can mistake these physiological symptoms, which can be easily explained by basic physiology for evidence of something else \u2013 such as a chemical, toxin etc. And we know these can spread very quickly in crowded environments, usually by rumour and also line of sight.\u201d<\/p>\n

Wessely said there was nothing unusual about the events at terminal 4 on Monday: \u201cIt happens all over the world every day, particularly in crowded spaces like schools, concerts, crowds, factory floors etc. The only reason this made the news was because of the fact it was at Heathrow and led to major flight disruptions.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"Police were called to Heathrow late on Monday afternoon when 21 people fell ill in Terminal 4. Initial…\n","protected":false},"author":2,"featured_media":410910,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[748,393,4884,12,1144,712,16,15,1764],"class_list":{"0":"post-410909","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-news","8":"tag-britain","9":"tag-england","10":"tag-great-britain","11":"tag-news","12":"tag-northern-ireland","13":"tag-scotland","14":"tag-uk","15":"tag-united-kingdom","16":"tag-wales"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/115175361581138276","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/410909","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=410909"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/410909\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/410910"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=410909"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=410909"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=410909"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}