The Martian soil is toxic due to relatively high concentrations of chlorine and associated compounds, such as perchlorates, which are hazardous to all known forms of life, even though some halotolerant microorganisms might be able to cope with enhanced perchlorate concentrations by drawing on physiological adaptations similar to those observed in the yeast Debaryomyces hansenii exposed in lab experiments to increasing NaClO4 concentrations.
