That is less than half a cup of liquid.

Fire Rescue Victoria station officer Luke Shearer said one person was taken to hospital for observation.

The spill was reported around 3.45pm on Friday and led to the evacuation of 60 people.

Mr Shearer said the toxic element originated from a gauge at the UGL Limited train and tram components factory in Gregory Street West.

"There was a malfunction in one of the pieces of machinery - and the liquid leaked out onto the floor," the Lucas-based firefighter said.

"It was an older-style machine.

READ MORE: Alfredton factory evacuated following mercury spill

"We used specialised HAZMAT equipment to clean it up and its been put in a recovery drum.

"UGL will now bring in a contractor to take it to a safe disposal area.

"Police also attended the spill and they notified Worksafe, which is the normal procedure."

Mr Shearer said the Lucas station was called out to two or three mercury spills a year..

Mercury poisoning is usually associated with seafood and gold mining.

Ingesting the heavy metal or its vapours can contribute to severe mood swings and behavioural issues.

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