A former Army medic, breaking 25 years of silence, said yesterday he followed orders to prepare phony records hiding high levels of radiation exposure to soldiers at four atomic tests in 1956 and 1957.

Van R. Brandon said his top secret medic group kept two sets of ledgers to record radiation readings from film badges worn by soldiers at the Yucca Flat, Nev., test site. The badges were designed to record the levels of radiation to which the men wearing them had been exposed.

One set of books showed no exposures over approved limits, while the other showed far greater exposures.

Pentagon spokesman James Freeman said he had no comment.

Two of Brandon's seven children were born mentally retarded, two others have developed arthritis and one of his two grandchildren had to have her blood changed at birth. He believes their problems are due to his radiation exposure.

Brandon, 45, who suffers from degenerative discogenic spine disease, said he was denied veterans benefits and told that the top secret Combined Operations Nuclear Medical Evaluation Team he says he was in never existed.

"The reply came back that no such team ever existed and if it never existed, I couldn't have been part of it," he said.