The stench was still in the air when I reached my Bukit Batok home at 8pm.

By then, I was feeling nauseous and had to close the windows.

The wind carrying the stench was blowing from the southern direction, where Singapore's petrochemical plants are located.

A light shower at 10pm finally got rid of the stench.

At midnight, after the rain, there came a cocoa smell that people living in the west are very familiar with.

Is the air quality in Singapore monitored, especially in the west?

How safe is the air that Singaporeans breathe?

Michael Eng Wee Chong