In the past 10 years, Dugway Proving Ground conducted 173 trials in the open air using germ-warfare "simulants" that the U.S. Army says are safe but which some scientists warn could still pose health threats.

That information was released by the Army for the first time Tuesday in response to Deseret News requests. Dugway spokeswoman Kathleen B. Whitaker said the information was also taken by Dugway scientists to congressional hearings on Tuesday about a proposed germ-warfare defense lab at Dugway, but the new information did not come up for discussion.The information is meant to supplement documents the Army released in 1977 about open-air biologic tests up to that time. Those earlier documents listed at least 84 experiments that used open-air tests at Dugway, some using simulants and some using actual biologic weapons (which were banned in 1969).

The new document shows that since 1978, the Army conducted eight major experiments embodying germ-warfare defenses at Dugway but those experiments required 173 trials in the open air at various Dugway test grids and facilities, including some tests on Army tanks sitting at Dugway's German Village residential area.

Four trials in 1978 used the simulant Serratia marcescens on its West Vertical Grid area in the desert. The test was to determine whether chemicals used to neutralize chemical weapons could do the same against biologic weapons.

The Army has claimed that organism is harmless and was used to simulate how more dangerous organisms would react. But the Army has since discontinued use of that simulant. Victor Yu, a specialist in infectious diseases, published an article in 1979 saying the organism can cause meningitis, wound infection and arthritis.

Of note, the Army sprayed the San Francisco Bay area in 1950 with Serratia marcescens in a test. Four days later a patient at Stanford University was found suffering an infection from that organism the first ever seen at the hospital. Ten more patients became infected in following days, and one died. The Army said it was a coincidence.

Years later, survivors of the man who died from the infection sued the Army, but their suit was thrown out of court when the judge ruled that the government was immune from suits over such national-defense experiments.

All of the other trials except three at Dugway since 1977 used the "niger variant" of the simulant Bacillus subtillus, which the Army also says is safe.

However, Rutger's professor Leonard A. Cole in a new book titled "Clouds of Secrecy" says medical textbooks say Bacillus subtillus may cause infections and invade the bloodstream in debilitating diseases. He said some scientists have also suggested that the organism can easily serve as a carrier for other dangerous viruses.

Whitaker, however, has said that the "niger" strain of the organism is harmless, although other strains are not.

That organism was used at Dugway to test new detectors, portable kits and alarm systems used to warn troops that they are under germ-warfare attack; to test whether certain chemicals might combat germ warfare; and to see how well systems designed to protect Army tanks from germ warfare work.

The last such test, according to the documents, was conducted in September 1986.

Documents released also said three trials at the "Target S Downwind Grid" used the simulant "MS2 (virus bacteriophage)." No information about the safety or danger of that particular organism was available.

Dugway scientists who work with it were in Washington for the hearings on the germ-warfare defenses lab, and local scientists contacted said they had never heard of it and figured that it was an organism used only in specialized research.

Documents said that organism was used in test to determine the feasibility of detecting germ-warfare aerosols and estimating their concentrations both during the day and night using a new device called the "Ultraviolet Laser Induced Fluorescence Detector."

During recent Army hearings about a proposed "biosafety level 4" lab at Dugway to test germ-warfare defenses, the Army had said that all biologic tests at Dugway during the past 10 years were unclassified but the results of one test were classified because it showed a weakness in national defense.

The Deseret News and other scientists and organizations had requested a list of those tests so that it could request more files on what work had been done recently at Dugway. The information released Tuesday was just three pages long, listing the eight major biologic experiments of the past 10 years, including a brief synopsis of each.