Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=214558
Story Retrieval Date: 6/19/2013 9:57:20 AM CST
Photo courtesy of Washington State University
Researchers took cell samples from rats bred for the research study. Researchers found a high incidence rate of obesity in later generations of rats.
Studies suggest environmental compounds may be toxic to future generations
Washington State University released a pair of studies Thursday suggesting that exposure to environmental compounds in one generation can have negative health consequences for later generations that had no actual contact with the compound.
Researchers said this is an example of epigenetic transgenerational inheritance, which is the non-genetic transfer of information through either the sperm or egg to later generations without being directly exposed to the compound.
Funded in part by the Department of Defense, the study focused on environmental exposure to the plastic compounds found in disposable water bottles and the hydrocarbons found in jet fuel.
According to research team member Michael Skinner, a professor in the School of Biological Sciences at Washington State University, these are common exposures for members of the military.
“Military compounds are sprayed with jet fuel to cut down on the dust,” Skinner said. “Plastic water bottles are a staple for the military. They are subjected to intense sun exposure that could break down the plastic.”
In each study, researchers exposed a pregnant female rat to a plastic mixture containing BPA, DEHP, DBP or jet fuel. The rats were then bred out across three additional generations.
According to Skinner, because the studies were not completed as a part of risk assessment, the levels of exposure were higher than normal environmental levels.
The results showed an increased incidence of multiple diseases such ovarian cancer, kidney disease -- the most surprising of which was obesity.
“This was something we had never seen before in this type of testing,” Skinner said. “And we found that the disease was being maintained across generations.”
Bruce Blumberg, a professor of cell development and biology at the University of California, Irvine, studies the impact of chemicals on the development of obesity.
Though Blumberg’s research involves exposure to levels of chemicals far below those deemed acceptable by the Environmental Protection Agency, he was encouraged by Skinner’s findings.
“It is gratifying to see that others are getting the same results,” Blumberg said.
In terms of the impact of the studies, Skinner said he will allow the public to decide what to do with the information.
“Society in general needs to make a decision about what these findings mean,” Skinner said.
According to Skinner, the potential for exposure is not limited to the military. Rural roads are sprayed with jet fuel and in the U.S. an estimated 60 million plastic water bottles are used each day.
“Especially in regards to the plastic water bottles, the public demands them,” Skinner said. “The public likes the convenience.”
Because the likelihood of people giving up this convenience is low, Skinner said researchers are tasked with finding an alternative.
“It becomes a question of how much [of the chemical] you can feasibly remove,” Skinner said. “You have to find a substitute, but that must also be safe.”