Must have been all that unregulated industry...

http://www.physorg.com/printnews.php?newsid=68907084

Astronomers detected unusually high quantities of carbon, the basis of
all terrestrial life, in an infant solar system around nearby star Beta
Pictoris, 63 light-years away.

"For years we've looked to this early forming solar system as one that
might be going through the same processes our own solar system did when
the rocky planets, including Earth, were forming," commented lead
author Aki Roberge, who began the research while at Carnegie's
Department of Terrestrial Magnetism. "But we got a big surprise--there
is much more carbon gas than we expected. Something very different is
going on." The research, published in the June 8, 2006, Nature,
suggests that either carbon-rich asteroids or comets, unlike any in our
own solar system, have vaporized, or that bodies outgassing
carbon-bearing species such as methane contribute the curious carbon
excess