The world faces a 29 percent chance of a nuclear attack sometime in the next decade, particularly with the addition of a handful of new nuclear power nations, a congressional survey released Wednesday found.

A survey of 85 top non-proliferation and national security experts from around the world, compiled by US Senator Richard Lugar, chairman of the Senate Foreign Relations Committee, also estimated that the risk of a major chemical or biological attack is greater than 30 percent, while the chance of a dirty bomb attack is pegged at 40 percent.

“I am hopeful that this study will contribute to the discussion inside and outside of governments about how we can strengthen non-proliferation efforts, improve safeguards around existing weapons and materials, bolster intelligence gathering and interdiction capabilities, and expand international cooperation in dealing with a threat that should deeply concern all governments and peoples,” Lugar said in a statement.

The survey, conducted in late 2004 and early 2005, found that 79 percent of the experts polled believe that their own country was not spending enough money on non-proliferation.

Most experts also believed that terrorists were more likely to carry out a nuclear attack than a government, and that terrorists were most likely to obtain a nuclear weapon or nuclear material through a black market transaction.