A British man's symptoms of anxiety were eventually traced to an unusual cause: his repeated exposure to a toxic substance while in the navy, a recent report of the man's case suggests.
The man worked as a naval engineer for five years. During this time, he was exposed almost daily to trichloroethylene (TCE), or "trike," a solvent used for cleaning and degreasing ships and aircraft, according to the case report, which was published Dec. 23 in the journal BMJ Case Reports.
Trichloroethylene is a colorless liquid with a sweet odor, and one of its main uses is to remove grease from metal parts, according to the U.S. Centers for Disease Control and Prevention.
In this case, the man said he and other members of the naval engineering crew would spray trichloroethylene from a can onto a cloth, and everyone who used it "seemed to get high from the fumes," the researchers wrote in the case report. He also said he "was regularly overcome to the point of feeling dizzy by trike." [27 Oddest Medical Cases]
These minor symptoms of dizziness and feeling "high" did not last long, but that feeling was probably the man's first clue that this was not a safe solvent to be using, said the case report author, Dr. Joshua Au Yeung, who treated the man 20 years later at Pennine Acute Hospitals NHS Trust in Manchester, England.
The man's exposure to trichloroethylene was made worse because the ships were not well ventilated, and the navy did not provide any protective equipment, such as masks, to limit the crew's ability to breathe in the vapors, Au Yeung told Live Science.
Identifying the culprit
The 24-year-old man first went to the hospital following a weeklong binge of alcohol in the navy — and not because he was concerned about his exposure to trichloroethylene.
When he went to the hospital, he was feeling extremely anxious, he was shaking (tremors) and he was breathing quickly. In addition, he told doctors he had a dull headache and blurry vision, and that he felt a tingling sensation on the right side of his face.
As doctors spoke with the man, they found out that he had graduated at the top of his naval class and that he had no history of regular or excessive use of alcohol before this incident. Doctors did not ask him detailed questions about his work, so his exposure to TCE never came up.
At the time, he was treated by a psychiatrist, who thought the man's symptoms had resulted from a withdrawal from alcohol, Au Yeung said. But over the next few months, his symptoms of anxiety became more frequent, until they wouldn't go away, according to the case report.
That's why the man's psychiatrist decided to send him to a toxicologist, a scientist who can detect exposure to poisonous substances, and a neuropsychiatrist, a psychiatrist who specializes in neurological illnesses, for a more comprehensive evaluation. These tests revealed that the man's symptoms of anxiety were linked to an unexpected culprit: his exposure to trichloroethylene as a naval engineer.
Regular exposure to trichloroethylene, which is a toxin, can affect every system in the body, Au Yeung said. Once the toxin is inhaled and gets into the blood, it can irritate and damage nerves directly, he said.
When nerves are irritated, they can cause pain, numbness and burning sensations, Au Yeung said. Damage to the nerves by a toxin can change the amount of neurotransmitters they release. For example, it can reduce levels of serotonin, which can lead to depression, he noted.
But, unfortunately for this man, the doctors identified the toxic culprit too late for them to reduce the man's absorption of TCE into his blood. He developed severe anxiety and depression from his exposure to the toxin, according to the report.
"The damage had been done in this case, so the man has not improved," Au Yeung said.
Twenty years later, the man has become dependent on alcohol — drinking two to three bottles of wine a day — and takes a variety of prescribed sedative medications to numb his anxiety, Au Yeung said.
Originally published on Live Science.