This should work for you...
Code:
sub EVENT_HATE_LIST {
if ($hate_state == 1 && $client && $client->GetLevel() > ($mlevel + 15) && $npc->GetEntityVariable("removed") != 1) {
$npc->RemoveItem(132522);
$npc->SetEntityVariable("removed", 1); #so it stops trying to remove the item when more people aggro it
}
}