They are not using DNA to perform cryptography (or any thing else).

from the original abstract:
In this project, We do not intended to utilize real DNA to perform the cryptography process; rather, We will introduce a new cryptography method based on central dogma of molecular biology. Since this method simulates some critical processes in central dogma, it is a pseudo DNA cryptography method.

The human body contains about 100g of DNA. You're saying about 2E15 grams, or 20 trillion human body's worth, of DNA is not only released into the atmosphere but then escapes the earths gravitational pull and enters interplanetary space.
Sounds unlikely.

http://en.wikipedia.org/wiki/Runaway_evolution

for keeping track of all the ideas and bits of informatation.
journler