Plastics chemical harms brain function in monkeys

A boy carries used plastic bottles in a shop which will be sent to recycling plants in Dhaka in this January 29, 2007 file photo.

NEW YORK (Reuters Health) - Scientists reported this week new evidence that low doses of the chemical bisphenol A (BPA), widely used to make plastic food and drinking containers, can impair brain function in primates, extending the findings of previous research conducted in rats.

Whether the amount of BPA that leaches out of containers into food and beverages represents an environmental risk is a subject of controversy.

"Our primate model indicates that BPA could negatively affect brain function in humans," study investigator Tibor Hajszan said in a press release from the Yale University School of Medicine in New Haven, Connecticut.

Hajszan and colleagues examined the influence of continuous exposure to BPA at a daily dose representing the US Environmental Protection Agency's current reference safe daily limit (50 micrograms per kilogram) in young adult African green monkeys.

According to a report in Proceedings of the National Academy of Sciences this week, BPA completely abolished the formation of some nerve connections in two key regions of the brain - the hippocampus and prefrontal cortex.

These findings have "profound implications," the investigators maintain, given the critical role of these nerve connections in cognition and mood.

"Based on these findings, we think the EPA may wish to consider lowering its 'safe daily limit' for human BPA consumption," Hajszan said.

SOURCE: Proceedings of the National Academy of Sciences, September 2, 2008.