The workers were rushed to a nearby hospital after they complained of irritation in eyes and breathlessness, police said.
A fire brigade spokesperson said the unknown odour was also reported from areas adjoining the Sanjay Gandhi National Park in northern suburb Borivli.
A total of 29 complaints were received by the 1916 control room regarding an unknown odour, which has considerably reduced now.
TV channel reporter, his wife and mother die of suffocation; front door has struggle marks.
Two employees at the ice manufacturing unit at Kasimedu fainted after noxious gas leaked on Wednesday morning.
The accident happened around 4 p.m. on Saturday, when the ship owned by the Fujian Shipping Company was being repaired.
The incident took place around 4 pm at the company located in Palghar-Tarapur MIDC, when the work of filling the gas was on, an official said.
While two have been discharged, one is under observation after hospitalisation as they complained of uneasiness.
A Paris police spokeswoman said several injuries have been reported to police but no deaths.