It’s a bit hard to have data of long term effects on things that are new
Very true so lets monitor the passengers and not the crew, its a bit difficult to approach the health and safety reps without any data to back it up. Perhaps if a couple of crew develop some nasty cancer or just drop dead there might be something to go on. Might be a bit late for the crew involved but that's OK because;
Like most shiftworkers part of a pilots pay reflects an unavoidable downside attached with working unusual hours