Barium is a silvery-white metal with compounds that are used by the oil and gas industries to help with drilling. It is also used for making paint, bricks, ceramics, glass and rubber.
Some forms of barium compounds also are used by doctors to perform medical tests and to take X-rays.
Ingesting concentrated levels of barium can cause gastrointestinal problems and muscular weakness, kidney damage, difficulty breathing, changes in heart rhythm, paralysis and possibly death.
Source: Centers for Disease Control and Prevention
When Liesa Hill first started feeling ill in 2011, she turned to her husband for help. Dr. Hal Hill was, after all, a respected infectious disease physician who practiced at hospitals across the area.
The year dragged on, and her condition only worsened. None of her treatments seemed to work, not even surgery. She had no way to trace the source of the bewildering illness -- until one morning this March when she spotted something strange.
"I found my husband putting an unidentified substance in my coffee, as he usually prepared my morning coffee for me," she wrote in a court document.
She worried her suspicions seemed a little paranoid, but she secretly called the Lookout Mountain, Tenn., police, who took a sample of the coffee and sent it to a lab for testing.
She immediately stopped drinking the morning brew, and her health dramatically improved.
"You can chalk that up to coincidence -- until you get the lab results of the coffee," said Liesa Hill's attorney, Chrissy Mincy. "Then it doesn't seem like so much of a coincidence."
Last week, the lab's test results came back and confirmed Liesa Hill's worst fears: The coffee contained extreme levels of barium, a toxic heavy metal.
The investigators further confirmed her suspicions: The symptoms of her earlier illness were consistent with heavy metal poisoning.
"Before the results, everything was so incredible. Because it is hard to believe, it really is," said Mincy, who has worked with attorneys Bill Speek and Gerald Webb on the case.
On Friday morning, Liesa Hill's attorneys filed an order of protection in Hamilton County Circuit Court, and Hal Hill, 52, was served with it that evening. Since then, he has not been allowed near the family home.
When reached at her home Monday, Liesa Hill, a pharmacist, referred all questions about the case to her attorneys. The couple -- who have been married 14 years -- have two children, ages 12 and 11.
A now 5-month-old criminal investigation is being handled by the Lookout Mountain Police Department and the Hamilton County Sheriff's Office. No criminal charges had been filed as of Monday.
Hal Hill did not respond Monday to messages to his cellphone requesting comment, and his office declined to comment.
He practices at Infectious Disease Physicians, but he also holds staff privileges at Memorial Hospital, Erlanger at Hutcheson and Parkridge Medical Center.
His licensure information shows no disciplinary action or criminal offenses. In March, he was nominated by the Chattanooga and Hamilton County Medical Society as a top local physician for National Doctor's Day.
Rae Young Bond, executive director of the Chattanooga and Hamilton County Medical Society, said the society typically suspends its disciplinary proceedings until such accusations are resolved in the legal forum.
"The Medical Society takes this matter very seriously and has a process to review the membership status of a member physician who has been convicted of a felony or found guilty of unprofessional conduct that brings the medical profession into disrepute," Bond wrote in an email.
It is too early to tell whether Hal Hill's medical license will be affected by the accusations.
"There is no state law or rule that prompts automatic action against a health professional's license when he or she is accused or charged with a crime," said Shelley Walker, spokeswoman for the Tennessee Department of Health. "However, the boards have broad discretion to impose disciplinary action as deemed necessary."
During the months that the secret investigation was conducted, Mincy describes Liesa Hill living in a grueling "game of chess," where she scrupulously eyed every food and drink in the house and wondered if her husband suspected her own suspicions.
"I'm so glad she's able to be in the house by herself now. Because she went through hell," said Mincy. "This weekend she finally got a good night's sleep for the first time in months."
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