Staffordshire Fire and Rescue Service went to an incident at Queen’s Hospital and Hobbycraft, Burton-on-Trent yesterday.
Two fire engines from Longton and one from Burton attended, after four Hobbycraft employees went to the hospital's A&E department after coming into contact with the substance.
The powder was later identified as Napthalene, which is a low risk product, and used to fumigate products shipped from abroad.
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A dry day with sunshine but cloud amounts increasing for the afternoon. Feeling warm in sunshine away from the Lincolnshire coast.
It will be feeling warm in the sunshine with mostly light winds, although it will turn breezier in the afternoon.
Detectives have launched an investigation after a schoolboy was hurt in a stabbing in Birmingham.