In the first line of your JS code:
select.addEventListener('change', getSelection(this), false);
you're invoking getSelection by placing (this) behind the function reference. That is most likely not what you want, because you're now passing the return value of that call to addEventListener, instead of a reference to the actual function itself.
In a function invoked by addEventListener the value for this will automatically be set to the object the listener is attached to, productLineSelect in this case.
If that is what you want, you can just pass the function reference and this will in this example be select in invocations from addEventListener:
select.addEventListener('change', getSelection, false);
If that is not what you want, you'd best bind your value for this to the function you're passing to addEventListener:
var thisArg = { custom: 'object' };
select.addEventListener('change', getSelection.bind(thisArg), false);
The .bind part is also a call, but this call just returns the same function we're calling bind on, with the value for this inside that function scope fixed to thisArg, effectively overriding the dynamic nature of this-binding.
To get to your actual question: "How to pass parameters to function in addEventListener?"
You would have to use an additional function definition:
var globalVar = 'global';
productLineSelect.addEventListener('change', function(event) {
var localVar = 'local';
getSelection(event, this, globalVar, localVar);
}, false);
Now we pass the event object, a reference to the value of this inside the callback of addEventListener, a variable defined and initialised inside that callback, and a variable from outside the entire addEventListener call to your own getSelection function.
We also might again have an object of our choice to be this inside the outer callback:
var thisArg = { custom: 'object' };
var globalVar = 'global';
productLineSelect.addEventListener('change', function(event) {
var localVar = 'local';
getSelection(event, this, globalVar, localVar);
}.bind(thisArg), false);