I can almost feel the gritty sensation I had at the back of my throat when high levels of air pollution settled over London a few weeks ago.
Researchers have found that short-term air pollution - like that experienced in parts of the UK recently - can cause serious health problems. It increases the risk of developing an irregular heartbeat and blood clots in the lungs.
It's no surprise that air pollution is bad for our health. But increasing evidence that even small amounts can be dangerous should motivate us to do more about it.