The street was quiet all afternoon -- now and then a dog barked, squirrels chattered or a car drove by -- but otherwise all was calm.
Even the investigators searching the stone home at 102 Fairy Trail worked quietly, slipping in and out of the house as neighbors watched.
For more than two hours Tuesday afternoon, investigators from the Hamilton County Sheriff's Office and Lookout Mountain Police Department searched the home of Dr. Hal Hill and his wife, Liesa.
Officials carried bags, backpacks and envelops labeled "Evidence" into Hill's house. They also photographed the inside of a car in the driveway.
On Friday, Liesa Hill filed an order of protection against her husband in Hamilton County Circuit Court after suspecting that her husband was poisoning her coffee. She had been ill since 2011, but doctors had been unable to pinpoint the cause of her condition, which steadily worsened.
One morning she saw her husband, a well-known physician, slip an unidentified substance into her morning cup of coffee, she said. She provided a sample to Lookout Mountain police, and test results confirmed last week that the coffee contained high levels of barium, a toxic heavy metal.
After she stopped drinking the coffee, Liesa Hill's health improved significantly, said her attorney, Chrissy Mincy.
Requests for comment left on Hal Hill's cellphone were not returned Tuesday.
No charges have been filed in the case. The sheriff's office and Lookout Mountain police said the investigation is ongoing and did not release any details on the case Tuesday.
Barium is a metal element used by the medical industry for some imaging tests, said Phillip Smith, a pharmacist at Access Pharmacy in Hixson.
According to the Centers for Disease Control and Prevention, it is often used as a contrasting agent in procedures such as X-rays or CT scans.
Reading from the Pharmacist's Letter, a publication that advises pharmacists, Smith said soluble barium is used in mouse poison.
At low doses, barium affects the nervous system and causes cardiac irregularities, tremors and paralysis, Smith said, but it's not a substance that's easy to come by.
"Somebody would have to actively search this out," he said. "This is not something that a pharmacy would stock."
Smith said he thought nuclear pharmacies -- which directly serve the medical industry, not the public -- would sell barium.
"A nuclear pharmacy would have it, but there is such good security on those things, I don't think you could just walk out with barium," he said. "They're closed-door pharmacies. They are not open to the public. They serve hospitals, like for the imaging tests."
Contact staff writer Shelly Bradbury at email@example.com or 423-757-6476.