Agent Orange Linked to Parkinson's, Heart Disease

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July 25

There was also "limited or suggestive evidence" between a parent's exposure to herbicides and spina bifida in offspring, along with a call for more studies on health issues in the children of veterans.

There was "inadequate or insufficient evidence" to correlate the herbicides with many other cancers, including esophageal, stomach, colorectal and pancreatic; with miscarriages, stillbirths or low birth weight in the offspring of exposed veterans or with neurodegenerative diseases other than Parkinson's. However, the committee found "limited or suggestive evidence of no association" in miscarriages after a father's exposure to TCDD.

The committee noted there had been little or no follow-up on previous, similar recommendations.

More connections between exposure to these herbicides and different health problems are likely to come to light in the future, experts predicted.

"As we grow older, we become more fragile, and problems may not show up until we get more fragile," said Keith A. Young, vice chair for research at the Texas A&M Health Science Center College of Medicine, in the department of psychiatry and behavioral science. He is also neuroimaging and genetics core leader at the VA Center of Excellence for Research on Returning War Veterans at the Central Texas Veterans Health Care System.

"Differences tend to accumulate, and diagnoses get more sure and valid," he said. "As time goes on, the underlying pathology starts to break through, and we're able to see it more clearly. The chemical exposure did some damage that starts to be expressed as our bodies become more fragile."

The evidence "certainly point to the value of collecting lots of data on lots of different conditions to understand the effects of the environment on our bodies," Young said.

More information

The Institute of Medicine has the full report.

SOURCES: Richard A. Fenske, Ph.D., associate chair, Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle; Deborah Cory-Slechta, Ph.D., professor, environmental medicine, University of Rochester Medical Center; Keith A. Young, Ph.D., vice chair, research, Texas A&M Health Science Center College of Medicine, department of psychiatry and behavioral science, neuroimaging and genetics core leader, VA Center of Excellence for Research on Returning War Veterans at the Central Texas Veterans Health Care System; July 24, 2009, Institute of Medicine report