Psychosomatic effects may be contributing to the symptoms of headaches, fatigue, or respiratory issues being reported by some residents of East Palestine, Ohio, following a hazardous chemical spill last month, experts say.
But "psychosomatic" does not mean that the symptoms are made up, according to experts. There is a body of evidence that suggests that smelling chemicals believed to be dangerous can induce feelings of stress and fear, which may lead to physical symptoms.
"If you're in the presence of something where there's a strong odor in the air, and you're concerned about the impact of it because you don't really understand the chemical that produce the odor, you probably start even breathing a little bit differently that can change your heart rate that can change all manner of physiological responses," Pamela Dalton, Ph.D., a researcher at the Monell Chemical Senses Center, told ABC News.
Researchers have done studies where they have misled people about the danger of a chemical they are smelling and shown that they will experience symptoms under those conditions.
"I can generate these symptoms so easily in an experimental situation and that's in a situation where I've already told people…they've signed an informed consent and I'm telling them, I'm not going to hurt you, nothing about this is dangerous, and they still come out of the experience complaining about the same constellation of symptoms," Dalton said.
It's been four weeks since a Norfolk Southern train derailed in the town on the Ohio-Pennsylvania border, releasing vinyl chloride, ethyl acrylate and isobutylene into the environment -- chemicals that are considered to be very toxic, possibly even carcinogenic with high exposures. These chemicals have been known to cause symptoms including drowsiness, lethargy, headaches and nausea.
Homeowners have been complaining of an array of symptoms including eye and skin irritation as well as nausea and headaches. Recently, a medical clinic opened to address those with health questions and concerns so far -- and that they continue to test.
The regional administrator for the Environmental Protection Agency, Debra Shore, told residents this week that officials had not found any chemical levels that posed a health concern.
Air monitoring has not detected any levels of health concern in the East Palestine community since the chemical fire went out on Feb. 8, according to a statement from the EPA. Yet, there are reports that the smell has lingered around the contamination site.
"We call it interoception. It's like an awareness of how you're feeling, across your body. Some people are more likely to scan that than others. But when you think you might be exposed to something harmful, it makes perfect sense to think 'how am I feeling' right?" Dalton said.
There continues to be many unknowns about the level of exposure, concentration of chemicals, and potential harm to health within the community.
"People are very suggestible when it comes to odors. Having said that, a lot of these irritants do cause a lot of chest congestion, nasal irritation, allergic reactions, and they operate on the autonomic nervous system which will affect breathing, [congestion] of the nose, eye watering and so on," Richard Doty, Ph.D., director of the smell and taste center at the Perelman School of Medicine, University of Pennsylvania, told ABC News.
The belief that an odor may cause bodily harm may be linked to stress and fear and thus, contribute to a bodily response like an increased heart or respiratory rate.
"People don't like that term [psychosomatic] because it makes them feel like they're somehow creating these symptoms. I like to say that it really happens independently of anyone's wish or desire to feel that but it's an adaptive response to scanning how you feel in the presence of something that you believe might be dangerous," Dalton said.
An emotional town hall in East Palestine on Thursday led to residents conveying their frustration with state and federal officials as they expressed their lack of trust and demanded to know why some community members were feeling sick.
"The fact that people are uprooted from their houses, they're stressed, they coughed and smelled [the chemicals] and then they couldn't drink the drinking water…and you add all those things together, people aren't going to believe there's no problem," Doty said.
In terms of what people can do, experts emphasized relieving stress may be helpful but that it's difficult to break the mind-body connection.
"Certainly, I would recommend everybody try some stress relieving…but there isn't a magic bullet, there isn't something good we can give them to smell that's going to break this association. I wish there were," Dalton said.