Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

Samuel L. Jackson is not impressed with Beijing's pollution.

The actor, who is in China with Scarlett Johansson to promote "Captain America: The Winter Soldier," has been tweeting over the past few days about the abysmal air quality index (AQI) in the smoggy city.

The U.S. Embassy in China monitors air quality for PM2.5, air particulates smaller than 2.5 microns and considered dangerous to human health, and has drawn ire from Beijing for posting the readings on its popular Twitter feed.

While Jackson expressed his concern over the AQI reading of 312 on Tuesday, the levels have been far higher -- and had reached 425 by Wednesday evening.

In February the AQI topped out at 500, which is 20 times the level considered safe by the World Health Organization.

-Marian Smith