The Viking biological investigations: review and status.
The three experimental approaches incorporated into the Viking biology instrument have yielded results that are most readily explained as nonbiological phenomena. The predominant view among investigators trying to simulate the Mars results is that the surface material of Mars contains strongly oxidizing compounds which would account for many of the more intense reactions seen on Mars. Other mechanisms are also currently being proposed and studied.
D055598:Chemical Phenomena; D002621:Chemistry; D005118:Extraterrestrial Environment; D012987:Soil
D012987:Soil