BY AMBER SMITH

Rescuers whose jobs take them to clandestine methamphetamine labs risk exposure to chemicals that can cause what appears to be permanent damage to their memory-making ability.

Specialists in anesthesiology and neurology at Upstate Medical University tell about a middle-aged firefighter who developed profound anterograde amnesia in 2001 after he was exposed to fumes from spilled material that was used to synthesize meth.

Chemicals commonly used in labs that produce the illegal stimulant are known to cause headaches, respiratory and eye irritation, and nausea and vomiting. Exposure to certain toxic chemicals can produce detrimental cognitive deficits, including amnesia. In a study from 2009, more than three-quarters of police officers reported memory loss after exposure to clandestine meth labs.

Amnesia is memory loss, which may be partial or complete and may relate to stored memories or the ability to commit something new to memory. Anterograde amnesia is when the ability to memorize new things is impaired. Its development indicates that particular regions of the brain have been affected.

Awss Zidan, MD, and Amy Sanders, MD, write about the firefighter‘s case in the March issue of the Journal of Neurology and Stroke.

The firefighter lost consciousness and was hospitalized. He had trouble recalling events of the recent past. “He could not remember dates or names for more than a few minutes,” the researchers write. After he went home, he developed “out of body experiences,” generalized shaking, angry outbursts, depressed moods and impaired cognitive functioning. He had trouble memorizing new things.

The man sought care at Upstate University Hospital 12 years after the incident.

“Although there has been no improvement in his memory impairment since the time of the injury, he has learned to cope with his limitations,” Zidan and Sanders write. “His family provides him with written notes, organizing his chores and tasks, such as shopping or household maintenance, on a daily basis; he is able to follow these instructions. He is able to drive with the help of a global positioning device.”

The researchers suggest the connection between meth lab exposure and memory deficits warrants further study.

People with anterograde amnesia may:

-- repeat comments or questions several times.

-- not recognize people they have just met.

-- have suffered damage to the hippocampus or medial temporal lobe of their brains.

-- retain the ability to learn new skills and habits (procedural memory).

-- lose the ability to recollect some facts (declarative memory). While they might not recall autobiographical information, they may be able to remember language, history and geography.

-- recover functioning for some memories, over time, if the damage is limited to one side of the brain.

This article appears in the fall 2016 issue of Upstate Health magazine.