Mars covered in toxic chemicals that can wipe out living organisms, tests reveal

Discovery has major implications for hunt for alien life on the red planet as it means any evidence is likely to be buried deep underground

The chances of anything coming from Mars have taken a downward turn with the finding that the surface of the red planet contains a "toxic cocktail" of chemicals that can wipe out living organisms.

Experiments with compounds found in the Martian soil show that they are turned into potent bactericides by the ultraviolet light that bathes the planet, effectively sterilising the upper layers of the dusty landscape.