The blast happened in a house in Drogheda, Co Louth, at around 4.20pm and caused internal structural damage to the property.
The girls, who are aged between 12 and 14, were taken to Our Lady of Lourdes Hospital in Drogheda.
A Garda spokesman said all had suffered "burns related injuries".
The extent of the injuries are not yet known.
It is not yet clear why the aerosol exploded.
The house has been sealed off to facilitate forensic examination.
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