The narrator says that Natasha is wrong about Irene: Irene needs and loves her job, as it's the only thing that keeps her loneliness in check. She takes her time looking at items to force everyone who goes through security to look at her. When people greet her, she feels as though she expands—though she never responds. Most of all, Irene wishes that she could take her gloves off and actually touch the items in the bins.
Irene illustrates an extreme case of loneliness: she's clearly depressed as a result of her isolation, and importantly, she recognizes that human connection has the power to save and heal her. In longing to take her gloves off, it seems that Irene wants to break down the barriers that keep her from fully connecting with the world around her. In addition, Irene’s job at a place that deals with immigration issues suggests that immigration is lonely for people on both sides.
Last night was awful for Irene. She felt as though her loneliness wanted to swallow her whole. Irene recognizes Natasha when she sees her: she's been there every day for the last week. When Natasha looks up at Irene, Irene feels better. She thinks that Natasha looks just as desperate as she feels, and she smiles and greets Natasha in her mind. As Irene studies the Nirvana phone case, she thinks the picture of the baby is indecent and feels as though she's the one underwater. She wants to confiscate it, but has no reason to.
The Nirvana album cover in question is a photo of a nude baby in a pool, swimming towards a dollar bill. Here, the fact that Irene derives this type of connection from a stranger's phone case suggests that opportunities for human connection appear in unlikely places.