It's interesting and ironic that a baby's gas mask could be just as dangerous - and lethal - as the event they were designed to protect against. Can you think of story ideas where a government gives people equipment that they say is to help them but actually harms them? Lots of dystopian futures use this sort of thinking as a starting point. In Hugh Howey's gripping science fiction novel Wool the people live underground in metal silos and there are all sorts of dangerous secrets being kept by the people in charge. Telling you anymore than that would spoil the story though! In Matched by Ally Condie, young people have their romantic partners chosen for them by the Society's technology. This story follows Cassia who realises something has gone wrong in the seemingly perfect world and sets out to discover the truth.
This object may also inspire you to write a scary story about war. You may also want to look at the First World War Death Plaque artefact for more ideas.