41.   Nightmarish chemical agents, like the nerve gas that sickened and killed Japanese commuters, can be concocted in terrorist labs.

42.   Now, he said, guards are more likely to use pepper gas and other chemical agents to coerce prisoners into complying with orders.

43.   One chemical agent would solidify the triggering mechanism, rendering the mine temporarily safe.

44.   One positive exception may be at Hanford, where scientists have developed a method for treating chromium-contaminated water with chemical agents.

45.   Pentagon analysts suspect that Iraq retains biological agents such as anthrax, nerve gases such as VX and chemical agents such as mustard gas.

46.   Producing chemical agents such as mustard gas and sarin would take only a few months.

47.   --Requiring that chemical tracing agents, or taggants, be included in explosive materials.

48.   Russia especially needs help to start destroying its vast depots of chemical agents, shells and warheads.

49.   Some scientists and engineers have taken up the challenge by developing a variety of ways to expose and destroy rogue bacteria and chemical agents.

50.   Techniques for the detection of airborne chemical agents are much further along, experts said.