For over 10 years, Nasser Zawia, a professor of pharmacy at the University of Rhode Island has researched how early childhood lead exposure can contribute to Alzheimer’s disease.

According to the Center for Disease Control, Alzheimer’s is the most common type of dementia that begins with mild memory loss and potentially leads to loss of the ability to carry on a conversation and respond to the environment. As of 2018, the Alzheimer’s Association reports that roughly 5.7 million Americans are living with the disease, and there is currently no cure.

Zawia explained that there are two types of the disease: late onset and early onset. Early-onset Alzheimer’s occurs before the age of 65 and is typically genetic. People who develop Alzheimer’s over the age of 65, have no genetic predisposition. Five percent of patients with Alzheimer’s disease have early onset, while 95 percent of patients have late onset.

“This suggested to me that something in the environment, diet, and lifestyle may contribute as a risk factor since the disease occurred so sporadic and late,” Zawia said.

Zawia is a trained neurotoxicologist, educated in studying the adverse effects chemical substances have on the brain. He had been studying lead for a while and knew it interfered with cognitive processes. Prior research had been done regarding the effect of lead on children but no one before him had looked at its effect later on in life.

In his research, Zawia exposed young mice and rats to lead and then aged them for two years. He noticed that those who had been exposed to lead had an increase of biomarkers of proteins and tangles associated with Alzheimer’s disease. This became the first evidence that an environmental exposure can predetermine what can happen to people in old age.

“The problem was that mice, along with many other animals, do not get Alzheimer’s,” Zawia said. “So people believed us more when we did our research on monkey tissue.”

Zawia and his team were able to look at the brains of monkeys who had been exposed to lead 23 years prior.

“We were fortunate that a scientist was studying the impact of lead on monkeys born in the 1980s,” Zawia said. “When she retired, she gave up the monkeys and we were able to take them.”

By looking at the monkey tissue, Zawia again found that those who had exposure to lead in childhood had elevated levels of biomarkers of Alzheimer’s disease. As monkeys can get Alzheimer’s, his findings became widely accepted.

“I published the research in 2008 and it got a lot of media attention,” Zawia said.

He was featured both nationally and internationally on platforms such as CNN, ABC News and CBS. Since then, Zawia has continued his research into Alzheimer’s and gene-environment interaction.

According to the Association of Health Care Journalists, there is an expected 40 percent increase in Alzheimer’s incidence by 2025. Zawia and his students are currently working to develop drugs that will treat this disease.