It looks like Ubuntu uses ~/.bashrc, ~/.bash_profile, ~/.pam_profile, /etc/environment, and /etc/profile in very
~/.bashrc
~/.bash_profile
~/.pam_profile
/etc/environment
/etc/profile
I'd prerer to put all environment variables to different file and source it from $HOME/.xsessionrc. .xsessionrc is simply a shell script which is executed after the new X session by login manager like gdm, kdm or so.
source
$HOME/.xsessionrc
.xsessionrc