Air pollution is a growing concern in cities around the world, and seeing people on the streets wearing masks to block air pollution is increasingly common. What exactly are these masks intended to block – and more importantly, do they actually work? This month’s graphic in C&EN has the answers.
Volkswagen have been in the news for all the wrong reasons over the past week. The company admitted to installing a ‘defeat device’ in millions of cars which made it appear in emissions tests that they emitted far lower levels of particular pollutants than they actually did in normal road conditions. Plenty of articles have looked at the particulars of the scandal since the story broke last week, so as well as considering the pollutants involved in the VW story, here we’ll also take a closer look at how we use chemistry to remove pollutants from vehicle emissions.
Back in school, you’ll have learned that the air in our atmosphere is composed primarily of nitrogen, at 78%, and oxygen, at 21%, with a number of other trace gases. It’s to these trace gases we’re looking today – more specifically, at how human activity can result in the release of air pollution in to the atmosphere. Here, we examine a number of different chemical compounds that contribute to atmospheric pollution, their specific sources, and their effects.