`it is a very bad idea to set LD_LIBRARY_PATH in your login profiles (.bashrc, .cshrc, etc) as doing so exposes all applications you start or use to this!
read this blurb for more information on the subject: https://www.hpc.dtu.dk/?page_id=1180
Instead write individual wrappers for specific applications that require such a setting, along with any other variables. Here’s a quick example:
~$ cat /usr/local/bin/dtk
#! /bin/bash
PREFIX=/usr/local/dtk
export LD_LIBRARY_PATH=$PREFIX
exec “$PREFIX/dtk” “$@”