Firefighters in Norwalk arrived at the blaze on Meadow Street at about 1 p.m. on Monday, May 9, according to the Norwalk Fire Department.
Officials said the plastic burns at high temperatures, which caused the toxic smoke.
The fire spread from the 40-foot container to nearby products and to a car on a neighboring property, the fire department said.
The blaze was brought under control in about an hour, officials said.
The fire department said no injuries were reported.
An investigation into the cause of the fire is underway.
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