PHP exec不会在/ etc / environment中加载变量

I´m using Ubuntu.

I have a PHP script that needs to call a program in shell and get its output.

That program uses a shared library, so I need to set up the $LD_LIBRARY_PATH environment variable. As that program is used system wide, that setup is done on /etc/environment as follows:

/etc/environment file:
LD_LIBRARY_PATH=/path/to/my/shared/library/libmyshared.so

If I open a terminal and to look for the code, it is there:

$ env | grep LD_LIBRARY_PATH
LD_LIBRARY_PATH=/path/to/my/shared/library/libmyshared.so

Here is the PHP script that needs to call a program:

$cmd = "program";
exec ($cmd, $out);
var_dump($out);

I´m getting a empty dump and an error on PHP saying that the shared library was not found...

error while loading shared libraries: libmyshared.so: cannot open shared object file: No such file or directory

Well, if I issue in PHP:

$cmd = "env;";
exec ($cmd, $out);
var_dump($out);

The output show only a small number of apache variables, none that is being used in a normal terminal window.

What may be missing here so that my exec command works ?

Help appreciated...