Officers and paramedics attended to the girl at a property in Sutton Street (credit: Google Maps)
Police say they received reports the child was unresponsive at a property in Sutton Street at 4.12pm on Saturday, 11 December.
The girl was taken to an east London hospital where she was pronounced dead a short time later.
A special post-mortem examination is to be scheduled in due course.
At this time, the death is being treated as unexplained.
Officers say other people in the same building reported feeling unwell and received treatment including three people who remain in hospital.
Their condition is unknown.
A spokesperson for the Met Police said: “A sweep of the building was carried out by the London Fire Brigade and a quantity of chemicals, believed to be used for pest control, were discovered.
“They will be safely removed and an investigation will be carried out to determine how they came to be in the building.
“Enquiries into the circumstances are ongoing.”
For more on this story, and the latest on our other local and national news, listen to Time 107.5FM
Tags: east London, Shadwell