Sao Paulo air pollution - how bad is it? (places, cons, population)

[califantastic]

Sao Paulo air pollution - how bad is it?

I might be going to Sao Paulo, Brazil for a couple weeks. I was wondering how bad the air pollution is in Sao Paulo. Based on what I have read I would imagine that the air quality in Sao Paulo is terrible but sometimes what you read isn't completely true. Also are there any particular months where the air pollution in Sao Paulo is less severe?

Thank you for your help.

[Mr.Falcon]

For Sao Paulo,the rate is 19 micrograms of PM 2.5 per cubic meter (data for 2014) - almost twice the limit defined by the WHO.
Only 12% of the world's population lives in cities with clean air, and half of the world's inhabitants are in places where pollution rates are more than twice the rate considered reasonable by WHO.

It is less severe on summers.