21.   The mystery surrounding the derailment grew murkier on Tuesday, as toxicology tests showed that the engineer, the conductor, and three assistant conductors were all sober.

22.   The next step is toxicology tests to determine the cause of death.

23.   The result of toxicology tests were not yet available, he said.

24.   The total number could be higher still since not all coroners where heat deaths occurred performed toxicology tests.

25.   There had been no history of abusing drugs, but Schwartzberg and the pathologist wanted toxicology tests to be sure.

26.   Toxicology tests revealed that Noone had alcohol and sedatives in her system when she died.

27.   Toxicology tests showed no evidence of drugs.

28.   While the results of a toxicology test are pending, Douglas County Sheriff Ron Pierini said there was no indication of alcohol or drug use.

29.   While the results of toxicology tests will not be known for six weeks, county Medical Examiner Sunandan B. Singh has ruled that the deaths were from natural causes.

30.   Police were awaiting results of toxicology tests on driver Richard Gnida, he said.