Children whose mothers ate lots of ocean fish containing low levels of mercury while they were pregnant suffered no ill effects in a study conducted in the Indian Ocean country of Seychelles.

"These are people who eat fish 12 times a week, and we have not found any negative effects yet," said Dr. Gary J. Myers, professor of pediatrics and neurology at the University of Rochester.The study was published in Wednesday's Journal of the American Medical Association.

At elevated levels, mercury can be dangerous for humans and can cause severe neurological damage in unborn children. Fish are contaminated with mercury to different degrees throughout the world.

In the Seychelles, where 85 percent of the population eats fish every day, mercury contamination levels are comparable to those in the U.S. market.

The researchers tested the pregnant women for mercury levels in their bodies, then followed the development of 711 children until age 5 1/2. No adverse effects were found in a battery of tests in such areas as language, reading, arithmetic, spatial skills and social abilities.