A Brooklawn woman researched the effects of antifreeze on the human body leading up to the alleged fatal poisoning of her grandmother-in-law at a Deptford rehab center this weekend, Gloucester County Prosecutor Sean Dalton said.
Anne Castagna, 43, who will now face an upgraded charge of first-degree murder, allegedly slipped Mary Groatman, her husband’s grandmother, antifreeze in some form Sunday afternoon at the Deptford Center for Rehabilitation and Healthcare, where Groatman had been recovering after a fall, Dalton said.
By Sunday night, Groatman was unconscious and unresponsive and was taken to Underwood-Memorial Hospital in Woodbury, where doctors discovered ethylene glycol—the toxic chemical that is the primary ingredient in antifreeze—in her system.
Hospital staff called police, and signs quickly pointed to Castagna as the suspect, Dalton said. Groatman remained in the hospital until Thursday afternoon, when she was taken off life support and died.
“If it wasn’t for the exhaustive and important work by the emergency room, this lady might’ve gotten away with murder,” he said.
Dalton wouldn’t speculate on motive for the poisoning and couldn’t elaborate on more detail about the circumstances of the incident, citing the ongoing investigation in the case.
“At this point, we’re not at liberty to go into that level of detail,” he said.
Though Groatman had head injuries and some bruising following the fall, Dalton said they’re focused on the events specifically leading up to her death.
“She was in good health for someone 88 years of age,” he said.
Groatman had been in Castagna’s care at the family home for several years, Dalton said. Real estate records show Castagna and her husband purchased the home on North Wilson Avenue from Groatman in 2002.
Castagna, who was , remains in jail on default of $250,000 bail. After the upgraded murder charges are signed against her, which Dalton said should happen within the next 24 hours, that bail could increase.
Dalton called the poisoning “heart-wrenching” and “a sick act,” and said this kind of murder by poisoning is a rare act in the county. Ethylene glycol poisoning can happen after a victim ingests as little as 4 ounces of the sweet-tasting liquid, according to statistics from the National Institutes of Health, as the chemical damages organs like the brain, liver, kidneys and lungs.
“It’s just something that most of us would never even fathom,” Dalton said.
A call to the Deptford Center for Rehabilitation and Healthcare late Thursday afternoon wasn’t returned.