Downwinders may have a new worry: genetic damage.

A study of New Zealand Navy veterans who say they were exposed to atomic fallout found a striking rate of genetic damage, the kind that can cause cancer, says R.E. "Al" Rowland, a professor who headed the research team.

Utahns and others who lived downwind from the Nevada Test Site during open-air nuclear blasts of the 1950s and early '60s should have genetic testing, says Rowland, senior lecturer in genetics and plant biology at Massey University in Auckland.

"For downwinders, it's never over," said Mary Dickson, a Salt Lake City anti-nuclear activist who is a member of the group Downwinders United. "We have a lifetime of medical follow-up and the expenses. Now we have to worry about what radiation damage does to future generations."

In a telephone interview, Massey said that as far as official government records are concerned, "We have no idea whether (the navy veterans) were even exposed to anything" during the open-air tests in the central Pacific Ocean, which were dubbed Operation Grapple.

Radiation detection badges worn during the 1957-58 test series are no longer available. Also, Massey said he believes officials maintain the men were not exposed.

But medical evidence apparently indicates otherwise.

The New Zealand frigates Pukaki and Rotoiti were stationed between 20 and 150 nautical miles upwind from the detonations, which took place between Christmas Island and Malden Island in the central Pacific. Altogether, nine bombs were exploded in the experiments, carried out by the British government.

"After each explosion they turned around and, from what I was told, they sailed through ground zero," he said. "There's no indication how much radiation they received."

Veterans later expressed concern about radiation exposure and complained of a variety of ailments. In 1999, the government of New Zealand contributed a research grant of $100,000 in that country's currency to the New Zealand Nuclear Test Veterans Association. Other groups contributed a like amount, and Massey University used the money to carry out the research. The report was released May 14.

Researchers were careful to use veterans and a control group made of volunteers who matched the veterans in many aspects. One difference is that the former navy men tended to smoke more in their youth. However, the report says other studies found no link between smoking and this type of genetic problem, and a subdivision between smokers and nonsmokers found no significant causation.