ActionScript 3.0 :: Loading Bunch Of Images In For Loop

I need to load a bunch of images using a for loop looping through xml. This will be called over and over for various groups of images. Memory management is a major concern. In the for loop I create a loader

ActionScript Code:
var thumb_loader:Loader = new Loader();
var thumbContainer:Sprite = new Sprite();
thumb_loader.load (new URLRequest (panelViewer [categoryPanels [indexCategoryPanels][i]].@pathName));
// set the thumb node from xml
thumb_loader.contentLoaderInfo.addEventListener(Event.INIT, thumbLoaded);
thumbContainer.addChild(thumb_loader);

I also add the thumb loader as a child now in the init handler
ActionScript Code:
function thumbLoaded(e:Event):void {
//when all thumbs are loaded I set them alpha to 0 and then to 1, for a nice effect
var thumbTarget:Object = e.target.content;
thumbTarget.alpha = 0;
Tweener.addTween(thumbTarget, { time:1, alpha:1, transition:"easeOutSine"} );
}

The issue I have I keep adding sprites and loaders and this keeps sucking resources this is for an air app that has to run for several days cycling through hundreds of images. How to keep my resources low and load a group of images delete the loaders and then on the next cycle delete the previous group.