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WEDNESDAY, Nov. 27, 2013 (HealthDay News) -- Seniors with higher levels of PCBs in their bodies have poorer mental abilities than those with lower levels of the toxic chemicals, a new study finds.
PCBs -- polychlorinated biphenyls -- are chemicals that were used as coolants, insulating materials and lubricants in electric equipment. Although they were banned in the United States in 1979, PCBs are still found in the blood of many older people.
The study included more than 700 American seniors whose blood was analyzed to determine their levels of PCBs. The participants also underwent memory and physical-skills tests.
There was a significant association between higher PCB levels and poorer mental performance among people aged 70 to 84. This association also was seen to a lesser extent in people aged 60 to 69.
Women in the older age group had the largest decline in mental skills in relation to PCB levels in their body, according to the study published online Nov. 25 in the journal Environmental Health Perspectives.
"While most studies have looked at the impact of PCBs on infant development, our research shows that this toxin might affect us throughout our lives," study author Maryse Bouchard, of the University of Montreal, said in a university news release.
"Aging persons could be at particular risk because of higher cumulative exposure built up across a lifetime; susceptibility due to underlying medical conditions, such as vascular disorders; and diminished cognitive reserve capacity," Bouchard said.
The findings suggest that PCBs, even at levels generally considered to pose low or no risk, may contribute to mental deficits, she said.
The U.S. Environmental Protection Agency has more about the health effects of PCBs.