A year ago or so, I watched a security officer take a litre bottle of water through the security check. I asked for the supervisor and mentioned what I had just witnessed. He was courteous and understanding but said that it was permitted for security staff to bring food and bottles air side. I pointed out that it would only take one rogue (or threatened) staff member to bring in one or several bottles, which were ehm not filled with H2O, over a period of time and then, on a given day, pass them on to a "passenger". Even though he shared my concerns as far as I know the dispensation still stands! This is BRUSSELS, not some vague third world airport!