There are other signs: hemolysis, elevation of plasma K+ level and depression of Na+ , cardiac arrest, acute renal failure. Decomposition in the air is twice as fast as when the body is under water and four times as fast as underground, and may take from several days to several months depending on environmental conditions. The body may remain identifiable for many months. Some tissues, such as tendons and ligaments, are more resistant to decomposition, the uterus and prostate glands may last several months.