Catching the polluters
Measurement techniques can pinpoint emitters like unroadworthy trucks and broken gas pipes, finds Andy Extance, but are not yet widespread
‘Everybody pays for the sins of a few.’ In 1992, that sinful few included Los Angeles taxi cab companies. Using absorption spectroscopy technology the local district attorney found that a few taxi companies’ emissions broke legal limits. The suspects were forging certificates showing that their highly polluting taxis passed ‘smog checks’, so that they could carry on without being fixed. Today, spectroscopic analytical chemistry techniques can detect the worst cases. But there are many complex issues that will determine whether they become solutions in humanity’s struggle to bring pollution under control.
Roadside infrared spectrometry and plane- and satellite-based instruments are helping make polluters clean up their acts and enforce emissions trading schemes, saving money and the environment.