The pendant Savan is wearing around his neck is a modified bio hazard plaque.
The New York costumes are largely made from recycled material such as plastic sacks and water bottles: things that might conceivably have been salvaged and used by the characters.
The actors were wearing trainers inside the shoes or boots of their costumes.
Eleanor Tomlinson said that Sam Claflin who plays her brother in the film, treated her like a little sister throughout the shoot, even when they were not filming.