You can’t make some things up.  All Nippon Airlines is asking passengers to use the facilities before boarding.  Why?  Using the toilet will lighten the passenger, hence lightening their collective weight, meaning–are you ready for it?–fewer carbon emissions!  From the story:

A Japanese airline has started asking passengers to go to the toilet before boarding in a bid to reduce carbon emissions.All Nippon Airways (ANA) claims that empty bladders mean lighter passengers, a lighter aircraft and thus lower fuel use. Airline staff will be present at boarding gates in terminals to ask passengers waiting to fly to relieve themselves before boarding, The Independent reported. ANA hopes the weight saved will lead to a five-tonne reduction in carbon emissions over the course of 30 days.

Hey, how about also handing out fast acting laxatives?  There’s a planet to save! Like I said, somethings you just can’t make up.