A new study from Marshall University found that a common additive to diesel fuels intended to increase fuel economy is capable of traveling to the lungs where it can cause serious health effects.
Dr. Eric R. Blough of the Marshall University Center for Diagnostic Nanosystems said he and his colleagues found data that indicated a dose-dependent increase in concentration of cerium in the livers of animals exposed to the antiparticles. Cerium is a common additive to diesel fuel to increase the efficiency of automobiles.
"Nanotechnology is an evolving area of importance that's about to have applications in almost every aspect of our lives," Blough said. "There's already several hundred products available on the market that have nanomaterials in them."
The toxicity of those materials, Blough said, are of interest to many researchers.
The research was published in the International Journal of Nanomedicine last month.
The cerium has potential to travel from the lungs to the liver, Brough's study indicates. The increases were also linked to elevation of liver enzymes in the blood and evidence consistent with liver damage.
"The interesting thing is that it appears that these particles, if they are inhaled, can travel outside of the lung and to other organs," Blough said. "This is an animal study, so we still have a long way to go, but it appears that inhaled cerium oxide nanoparticles could lead to liver damage. What we found was histological evidence of changes at the cellular level and in changes of some of the enzymes in the blood that are predictive of liver damage."
Blough said he and the other research attempted to mimic the potential effects of exposure over decades.
"The reason that we did that was that it's possible that these particles could accumulate over time," he said.
"Given the ever-increasing use of nanomaterials in industry and in the products we buy, it is becoming increasingly important to understand if these substances may be harmful," Blough said. "To our knowledge, this is the first report to evaluate if inhaled cerium oxide nanoparticles exhibit toxic effects in the liver."
The cerium particles examined in the study are about 1/40,000 the width of a human hair.
Dr. Siva K. Nalabotu, the study's lead author and a Ph.D. student in Blough's lab, said, said the field of nanomaterials is not yet well understood, but interest is rapidly growing.
"Our studies show that cerium oxide nanoparticles are capable of entering the liver from the lungs through the circulation, where they show dose-dependent toxic effects on the liver. Our next step is to determine the mechanism of the toxicity."
The study was conducted with funds from the U.S. Department of Energy.
"We're huge proponents of advancing nanotechnology, so I don't want to come across as somebody who is trying to stall or prevent the development of research in this field," he said. "We're interested more in seeing if we can use these for biomedical applications also, specifically for the treatment of chronic disease and some of the things that are large portion of our health care expense.